About | BLOGS | Portfolio | Misc | Recommended | What's New | What's Hot

About | BLOGS | Portfolio | Misc | Recommended | What's New | What's Hot


Bibliography Options Menu

30 Jun 2022 at 01:45
Hide Abstracts   |   Hide Additional Links
Long bibliographies are displayed in blocks of 100 citations at a time. At the end of each block there is an option to load the next block.

Bibliography on: Invasive Species


Robert J. Robbins is a biologist, an educator, a science administrator, a publisher, an information technologist, and an IT leader and manager who specializes in advancing biomedical knowledge and supporting education through the application of information technology. More About:  RJR | OUR TEAM | OUR SERVICES | THIS WEBSITE

RJR: Recommended Bibliography 30 Jun 2022 at 01:45 Created: 

Invasive Species

Standard Definition: Invasive species are plants, animals, or pathogens that are non-native (or alien) to the ecosystem under consideration and whose introduction causes or is likely to cause harm. Although that definition allows a logical possibility that some species might be non-native and harmless, most of time it seems that invasive species and really bad critter (or weed) that should be eradicated are seen as equivalent phrases. But, there is a big conceptual problem with that notion: every species in every ecosystem started out in that ecosystem as an invader. If there were no invasive species, all of Hawaii would be nothing but bare volcanic rock. Without an invasion of species onto land, there would be no terrestrial ecosystems at all. For the entire history of life on Earth, the biosphere has responded to perturbation and to opportunity with evolutionary innovation and with physical movement. While one may raise economic or aesthetic arguments against invasive species, it is impossible to make such an argument on scientific grounds. Species movement — the occurrence of invasive species — is the way the biosphere responds to perturbation. One might even argue that species movement is the primary, short-term "healing" mechanism employed by the biosphere to respond to perturbation — to "damage." As with any healing process, the short-term effect may be aesthetically unappealing (who thinks scabs are appealing?), but the long-term effects can be glorious.

Created with PubMed® Query: "invasive species" OR "invasion biology" OR "alien species" OR "introduced species" NOT pmcbook NOT ispreviousversion

Citations The Papers (from PubMed®)


RevDate: 2022-06-29

Combillet L, Fabregat-Malé S, Mena S, et al (2022)

Pocillopora spp. growth analysis on restoration structures in an Eastern Tropical Pacific upwelling area.

PeerJ, 10:e13248 pii:13248.

Coral reefs in Culebra Bay (North Pacific of Costa Rica) are threatened by multiple anthropogenic disturbances including global warming, overfishing, eutrophication, and invasive species outbreaks. It is possible to assist their recovery by implementing ecological restoration techniques. This study used artificial hexagonal steel structures, called "spiders" to compare growth of Pocillopora spp. coral fragments of different sizes. Three initial fragment class sizes were used: 2, 5 and 8 cm, with each class size having 42 initial fragments. Changes in fragment length, width and area were measured monthly from January to December 2020. Results showed an overall survivorship of 70.21%, and no significant differences in survivorship and linear growth rate were detected between class sizes. The linear growth rates are 4.49 ± 1.19 cm year-1, 5.35 ± 1.48 cm year-1 and 3.25 ± 2.22 cm year-1 for the 2, 5 and 8 cm initial class sizes, respectively. Our results do not show significant differences in growth rates between the different initial fragment sizes. However, since small fragments (2 cm) present higher mortality during the first month, we recommend using larger fragments. In addition, coral fragments grew 48% more during the non-upwelling season, which may suggest that it might be more effective and safer to start the restoration efforts during this period.

RevDate: 2022-06-29

EFSA Panel on Plant Health (PLH), Bragard C, Baptista P, et al (2022)

Pest categorisation of Tetraleurodes perseae.

EFSA journal. European Food Safety Authority, 20(6):e07397 pii:EFS27397.

The EFSA Panel on Plant Health performed a pest categorisation of Tetraleurodes perseae (Hemiptera: Aleyrodidae), the red-banded whitefly, for the territory of the EU. T. perseae is a tropical and subtropical species that originated in the Neotropical region and has now spread and established in the USA (California and Florida), Israel and Lebanon. T. perseae is not listed in Commission Implementing Regulation (EU) 2019/2072. It is oligophagous on Lauraceae and most frequently reported on avocado (Persea americana), on which it is considered a minor or secondary pest. No evidence was found indicating damage to other plants. T. perseae larvae develop on the foliage and don't attack the fruit. The number of generations per year varies between one and ten. High populations may promote the growth of black sooty moulds on the foliage and fruit, and adults feeding on the buds can lead to deformed immature leaves and premature leaf drop. However, T. perseae populations are usually effectively controlled by hymenopteran parasitoids, at least one of which (Cales noacki) is widespread in the EU. The producers of organic avocados in the EU could encourage the use of C. noacki, although occasional outbreaks of T. perseae could temporarily impact the fruit quality. Adults disperse naturally by flying and all stages can be moved over long distances by the trade of infested plant material. Plants for planting provide potential pathways for entry and spread in the EU. Climatic conditions and availability of host plants in southern EU countries are conducive for establishment. Phytosanitary measures are available to reduce the risk. T. perseae satisfies all of the criteria that are within the remit of EFSA to assess for it to be regarded as a potential Union quarantine pest. However, this conclusion has a high uncertainty regarding magnitude of potential impact as the insect is a minor and sporadic pest in its current area of distribution.

RevDate: 2022-06-27

Coughlan NE, Dickey JWE, Dick JTA, et al (2022)

When worlds collide: Invader-driven benthic habitat complexity alters predatory impacts of invasive and native predatory fishes.

The Science of the total environment pii:S0048-9697(22)03973-0 [Epub ahead of print].

Interactions between multiple invasive alien species (IAS) might increase their ecological impacts, yet relatively few studies have attempted to quantify the effects of facilitative interactions on the success and impact of aquatic IAS. Further, the effect of abiotic factors, such as habitat structure, have lacked consideration in ecological impact prediction for many high-profile IAS, with most data acquired through simplified assessments that do not account for real environmental complexities. In the present study, we assessed a potential facilitative interaction between a predatory invasive fish, the Ponto-Caspian round goby (Neogobius melanostomus), and an invasive bivalve, the Asian clam (Corbicula fluminea). We compared N. melanostomus functional responses (feeding-rates under different prey densities) to a co-occurring endangered European native analogue fish, the bullhead (Cottus gobio), in the presence of increased levels of habitat complexity driven by the accumulation of dead C. fluminea biomass that persists within the environment (i.e. 0, 10, 20 empty bivalve shells). Habitat complexity significantly influenced predation, with consumption in the absence of shells being greater than where 10 or 20 shells were present. However, at the highest shell density, invasive N. melanostomus maximum feeding-rates and functional response ratios were substantially higher than those of native C. gobio. Further, the Relative Impact Potential metric, by combining per capita effects and population abundances, indicated that higher shell densities exacerbate the relative impact of the invader. It therefore appears that N. melanostomus can better tolerate higher IAS shell abundances when foraging at high prey densities, suggesting the occurrence of an important facilitative interaction. Our data are thus fully congruent with field data that link establishment success of N. melanostomus with the presence of C. fluminea. Overall, we show that invader-driven benthic habitat complexity can alter the feeding-rates and thus impacts of predatory fishes, and highlight the importance of inclusion of abiotic factors in impact prediction assessments for IAS.

RevDate: 2022-06-27

Hsouna J, Gritli T, Ilahi H, et al (2022)

Genotypic and symbiotic diversity studies of rhizobia nodulating Acacia saligna in Tunisia reveal two novel symbiovars within the Rhizobium leguminosarum complex and Bradyrhizobium.

Systematic and applied microbiology, 45(4):126343 pii:S0723-2020(22)00050-9 [Epub ahead of print].

Acacia saligna is an invasive alien species that has the ability to establish symbiotic relationships with rhizobia. In the present study, genotypic and symbiotic diversity of native rhizobia associated with A. saligna in Tunisia were studied. A total of 100 bacterial strains were selected and three different ribotypes were identified based on rrs PCR-RFLP analysis. Sequence analyses of rrs and four housekeeping genes (recA, atpD, gyrB and glnII) assigned 30 isolates to four putative new lineages and a single strain to Sinorhizobium meliloti. Thirteen slow-growing isolates representing the most dominant IGS (intergenic spacer) profile clustered distinctly from known rhizobia species within Bradyrhizobium with the closest related species being Bradyrhizobium shewense and Bradyrhizobium niftali, which had 95.17% and 95.1% sequence identity, respectively. Two slow-growing isolates, 1AS28L and 5AS6L, had B. frederekii as their closest species with a sequence identity of 95.2%, an indication that these strains could constitute a new lineage. Strains 1AS14I, 1AS12I and 6AS6 clustered distinctly from known rhizobia species but within the Rhizobium leguminosarum complex (Rlc) with the most closely related species being Rhizobium indicum with 96.3% sequence identity. Similarly, the remaining 11 strains showed 96.9 % and 97.2% similarity values with R. changzhiense and R. indicum, respectively. Based on nodC and nodA phylogenies and cross inoculation tests, these 14 strains of Rlc species clearly diverged from strains of Sinorhizobium and Rlc symbiovars, and formed a new symbiovar for which the name sv. "salignae" is proposed. Bacterial strains isolated in this study that were taxonomically assigned to Bradyrhizobium harbored different symbiotic genes and the data suggested a new symbiovar, for which sv. "cyanophyllae" is proposed. Isolates formed effective nodules on A. saligna.

RevDate: 2022-06-27

Wang B, Zhang K, Liu QX, et al (2022)

Long-distance facilitation of coastal ecosystem structure and resilience.

Proceedings of the National Academy of Sciences of the United States of America, 119(28):e2123274119.

Biotic interactions that hierarchically organize ecosystems by driving ecological and evolutionary processes across spatial scales are ubiquitous in our biosphere. Biotic interactions have been extensively studied at local and global scales, but how long-distance, cross-ecosystem interactions at intermediate landscape scales influence the structure, function, and resilience of ecological systems remains poorly understood. We used remote sensing, modeling, and field data to test the hypothesis that the long-distance impact of an invasive species dramatically affects one of the largest tidal flat ecosystems in East Asia. We found that the invasion of exotic cordgrass Spartina alterniflora can produce long-distance effects on native species up to 10 km away, driving decadal coastal ecosystem transitions. The invasive cordgrass at low elevations facilitated the expansion of the native reed Phragmites australis at high elevations, leading to the massive loss and reduced resilience of the iconic Suaeda salsa "Red Beach" marshes at intermediate elevations, largely as a consequence of reduced soil salinity across the landscape. Our results illustrate the complex role that long-distance interactions can play in shaping landscape structure and ecosystem resilience and in bridging the gap between local and global biotic interactions.

RevDate: 2022-06-27

Iwanycki Ahlstrand N, Gopalakrishnan S, Vieira FG, et al (2022)

Travel Tales of a Worldwide Weed: Genomic Signatures of Plantago major L. Reveal Distinct Genotypic Groups With Links to Colonial Trade Routes.

Frontiers in plant science, 13:838166.

Retracing pathways of historical species introductions is fundamental to understanding the factors involved in the successful colonization and spread, centuries after a species' establishment in an introduced range. Numerous plants have been introduced to regions outside their native ranges both intentionally and accidentally by European voyagers and early colonists making transoceanic journeys; however, records are scarce to document this. We use genotyping-by-sequencing and genotype-likelihood methods on the selfing, global weed, Plantago major, collected from 50 populations worldwide to investigate how patterns of genomic diversity are distributed among populations of this global weed. Although genomic differentiation among populations is found to be low, we identify six unique genotype groups showing very little sign of admixture and low degree of outcrossing among them. We show that genotype groups are latitudinally restricted, and that more than one successful genotype colonized and spread into the introduced ranges. With the exception of New Zealand, only one genotype group is present in the Southern Hemisphere. Three of the most prevalent genotypes present in the native Eurasian range gave rise to introduced populations in the Americas, Africa, Australia, and New Zealand, which could lend support to the hypothesis that P. major was unknowlingly dispersed by early European colonists. Dispersal of multiple successful genotypes is a likely reason for success. Genomic signatures and phylogeographic methods can provide new perspectives on the drivers behind the historic introductions and the successful colonization of introduced species, contributing to our understanding of the role of genomic variation for successful establishment of introduced taxa.

RevDate: 2022-06-27
CmpDate: 2022-06-27

Kaiser SW, Greenlees MJ, R Shine (2022)

Sex-based differences in the use of post-fire habitats by invasive cane toads (Rhinella marina).

Scientific reports, 12(1):10610.

Wildfires can modify habitat attributes, and those changes may differentially affect males versus females within a species if there is pre-existing niche divergence between the sexes. We used radio-tracking and dissections to study invasive cane toads (Rhinella marina), and performed transect counts on native frogs and cane toads 12 months after extensive fires in forests of eastern Australia. Both toads and native frogs were encountered more frequently in burned sites than in unburned sites. Most microhabitat features were similar between burned versus unburned areas, but fire had differential impacts on the ecology of male versus female toads. In burned areas females were less numerous but were larger, in better body condition, and had consumed more prey (especially, coleopterans and myriapods). The impact of fire on attributes of retreat-sites (e.g., temperature, density of vegetation cover) also differed between the sexes. More generally, intraspecific divergence in ecological traits within a species (as a function of body size as well as sex) may translate into substantial divergences in the impacts of habitat change.

RevDate: 2022-06-27
CmpDate: 2022-06-27

Hinckley ES, Miller HR, Lezberg A, et al (2022)

Interactions between tall oatgrass invasion and soil nitrogen cycling.

Oecologia, 199(2):419-426.

Increases in nitrogen (N) inputs to the biosphere can exacerbate the introduction and spread of invasive non-native plant species. Often, with elevated soil N levels, invasive plants establish and further enrich soil N pools, changing overall ecosystem function. This study examined the relationship between soil N cycling and an increasingly prevalent, invasive plant species, tall oatgrass (Arrhenatherum elatius subsp. elatius), in foothills ecosystems between the Colorado Rocky Mountains and the Denver-Boulder Metropolitan area-similar to many Western US grasslands and woodlands. It focused on investigating differences in soil N transformations, inorganic N pools, and vegetation characteristics across invaded and uninvaded plots at three sites in two seasons (summer and autumn). There was a statistically significant effect of invasion on rates of net N mineralization, but it was dependent on site and season (p = 0.046). Site had a statistically significant effect on soil moisture and aboveground biomass C:N (p < 0.04). The interactions of invasion x site were statistically significant for ammonium pools (p < 0.03). These findings suggest that A. elatius invasion can be associated with accelerated N cycling, but that the nature of the relationship differs by location and season in the foothills. More broadly, this study contributes to determining how the N cycle is shifting in grassland ecosystems subject to increasing pressures from anthropogenic change.

RevDate: 2022-06-25

Dobson B, Barry S, Maes-Prior R, et al (2022)

Predicting catchment suitability for biodiversity at national scales.

Water research, 221:118764 pii:S0043-1354(22)00717-5 [Epub ahead of print].

Biomonitoring of water quality and catchment management are often disconnected, due to mismatching scales. Considerable effort and money are spent each year on routine reach-scale surveying across many sites, particularly in countries like the UK, where nationwide sampling has been conducted using standardised techniques for many decades. Most of these traditional freshwater biomonitoring schemes focus on pre-defined indicators of organic pollution to compare observed vs expected subsets of common macroinvertebrate indicator species. Other taxa, including many threatened species, are often ignored due to their rarity, as are many invasive species, which are seen as undesirable despite becoming increasingly common and widespread in freshwaters, especially in urban ecosystems. Both these types of taxa are often monitored separately for reasons related to biodiversity concerns rather than for gauging water quality. Repurposing such data could therefore provide important new biomonitoring tools that can help catchment managers to directly link the water quality they aim to control with the biodiversity they are trying to protect. Here we used extensive data held in the England Non-Native and Rare/Protected species records that track these two groups of species as a proof-of-concept for linking catchment scale management of freshwater ecosystems and biodiversity to a range of potential drivers across England. We used national land use (Centre for Ecology and Hydrology land cover map) and water quality indicator (Environment Agency water quality data archive) datasets to predict, at the catchment scale, the presence or absence of 48 focal threatened or invasive species of concern routinely sampled by the English Environment Agency, with a median accuracy of 0.81 area under the receiver operating characteristic curve. A variety of water quality indicators and land-use types were useful in predictions, highlighting that future biomonitoring schemes could use such complementary measures to capture a wider spectrum of drivers and responses. In particular, the percentage of a catchment covered by freshwater was the single most important metric, reinforcing the need for space/habitat to support biodiversity, but we were also able to resolve a range of key environmental drivers for particular focal species. We show how our method could inform new catchment management approaches, by highlighting how key relationships can be identified and how to understand, visualise and prioritise catchments that are most suitable for restoration or water quality interventions. The scale of this work, in terms of number of species, drivers and locations, represents a significant step towards forging a new approach to catchment management that enables managers to link drivers they can control (water quality and land use) to the biota they are trying to protect (biodiversity).

RevDate: 2022-06-25

Yang JS, Qian ZH, Shi T, et al (2022)

Chromosome-level genome assembly of the aquatic plant Nymphoides indica reveals transposable element bursts and NBS-LRR gene family expansion shedding light on its invasiveness.

DNA research : an international journal for rapid publication of reports on genes and genomes pii:6617837 [Epub ahead of print].

Nymphoides indica, an aquatic plant, is an invasive species that causes both ecological and economic damage in North America and elsewhere. However, the lack of genomic data of N. indica limits the in-depth analysis of this invasive species. Here, we report a chromosome-level genome assembly of nine pseudochromosomes of N. indica with a total size of approximately 520 Mb. More than half of the N. indica genome consists of transposable elements (TEs), and a higher density of TEs around genes may play a significant role in response to an ever-changing environment by regulating the nearby gene. Additionally, our analysis revealed that N. indica only experienced a gamma (γ) whole-genome triplication event. Functional enrichment of the N. indica-specific and expanded gene families highlighted genes involved in the responses to hypoxia and plant-pathogen interactions, which may strengthen the ability to adapt to external challenges and improve ecological fitness. Furthermore, we identified 160 members of the nucleotide-binding site and leucine-rich repeat (NBS-LRR) gene family, which may be linked to the defense response. Collectively, the high-quality N. indica genome reported here opens a novel avenue to understand the evolution and rapid invasion of Nymphoides spp.

RevDate: 2022-06-25

Marcacci G, Grass I, Rao VS, et al (2022)

Functional diversity of farmland bees across rural-urban landscapes in a tropical megacity.

Ecological applications : a publication of the Ecological Society of America [Epub ahead of print].

Urbanization is a major threat to biodiversity and food security, as expanding cities, especially in the Global South, increasingly compete with natural and agricultural lands. However, the impact of urban expansion on agricultural biodiversity in tropical regions is overlooked. Here we assessed how urbanization affects the functional response of farmland bees, the most important pollinators for crop production. We sampled bees across three seasons in 36 conventional vegetable-producing farms spread along an urbanization gradient in Bengaluru, an Indian megacity. We investigated how landscape and local environmental drivers affected different functional traits (sociality, nesting behaviour, body size and specialization) and functional diversity (functional dispersion) of bee communities. We found that the functional responses to urbanization were trait specific with more positive than negative effects of grey area (sealed surfaces and buildings) on species richness, functional diversity and abundance of most functional groups. As expected, larger, solitary, cavity-nesting, and surprisingly, specialist bees benefitted from urbanization. In contrast to temperate cities, the abundance of ground-nesters increased in urban areas, presumably because larger patches of bare soil were still available besides roads and buildings. However, overall bee abundance and the abundance of social bees (85% of all bees) decreased with urbanization, threatening crop pollination. Crop diversity promoted taxonomic and functional diversity of bee communities. Locally, flower resources promoted the abundance of all functional groups, and natural vegetation could maintain diverse pollinator communities throughout the year, especially during the non-cropping season. However, exotic plants decreased functional diversity and bee specialization. To safeguard bees and their pollination services in urban farms, we recommend (1) to preserve semi-natural vegetation (hedges) around cropping fields to provide nesting opportunities for above-ground nesters, (2) to promote farm-level crop diversification of beneficial crops (e.g., pulses, vegetables and spices), (3) to maintain native natural vegetation along field-margins, (4) to control and remove invasive exotic plants that disrupt native plant-pollinator interactions. Overall, our results suggest that urban agriculture can maintain functionally diverse bee communities and, if managed in a sustainable manner, can be used to develop win-win solutions for biodiversity conservation of pollinators and food security in and around cities.

RevDate: 2022-06-24

Zhou L, Liu K, Zhao Y, et al (2022)

Increasing salinization of freshwater limits invasiveness of a live-bearing fish: Insights from behavioral and life-history traits.

Environmental pollution (Barking, Essex : 1987) pii:S0269-7491(22)00872-7 [Epub ahead of print].

Biological invasions and continued salinization of freshwater are two global issues with largely serious ecological consequences. Increasing salinity in freshwater systems, as an environmental stressor, may negatively affect normal life activities in fish. It has been documented that salinity limits the invasive success of alien species by mediating physiological and life-history performances, however, there are few studies on how salinity affects its invasive process via altered behaviors. Using wild-caught invasive western mosquitofish (Gambusia affinis) as animal model, in this study, we asked whether gradual increasing salinity affects behaviors (personality and mate choice decision here), life-history traits, as well as the correlation between them by exposing G. affiins to three levels salinity (freshwater, 10 and 20‰). Results showed that, with increased salinity, male tended to be shyer, less active, less sociable, and reduced desire to mate, and female tended to be shyer, less active and lost preferences for the larger male. Furthermore, across salinity treatments, male exhibited reduced body fat content and rising reproduction allocation, however, pregnant female revealed diametrically opposed trends. In addition, the correlation between life-history traits and behaviors was only identified in pregnant female. It seems that either salinity or life-history traits directly affects mosquitofish behaviors. In summary, our results partially emphasize the harmful consequences of salinity on both life-history traits and behavioral performances. These findings provide a novel perspective on how salinity potentially affect fish fitness via altering personalities, mate choice decisions, as well as body condition, and hence supports the idea that salinity could affect the spread of invasive mosquitofish.

RevDate: 2022-06-24

Ndabankulu K, Tsvuura Z, A Magadlela (2022)

Alien invasive Leucaena leucocephala successfully acquires nutrients by investing in below-ground biomass compared to native Vachellia nilotica in nutrient-amended soils in South Africa.

AoB PLANTS, 14(3):plac026 pii:plac026.

Soils in grasslands and savannas of southern Africa are acidic and nutrient-poor. Legume plants, such as Vachellia nilotica and alien invasive Leucaena leucocephala, are a major component of the vegetation there. Vachellia nilotica can establish in drought-prone environments, and is invasive in high rainfall areas. Leucaena leucocephala is an emerging invasive in South Africa and is ranked among the world's 100 most invasive alien species. Alien plants can invade native habitats through their adaptability to low-resource soils, and thus can out-compete and displace native vegetation. We investigated the effects of phosphorus (P) deficiency and soil acidity on legume-microbe symbiosis, nitrogen (N) nutrition and carbon (C) growth costs of these two legumes in grassland soils. We used as inoculum and growth substrate soils collected from a long-term (>65 years) nutrient and lime-addition trial, the Veld Fertilizer Trial (VFT), located at Ukulinga Research Farm near Pietermaritzburg in South Africa. We used soils from three VFT treatments: soils fertilized with superphosphate (336 kg ha-1) applied once per year (+P), soils fertilized with superphosphate (336 kg ha-1) applied once per year with dolomitic lime (2250 kg ha-1) applied once every 5 years (P+L) and soils with no superphosphate and no dolomitic lime applications (Control). Seeds of V. nilotica and L. leucocephala were germinated and grown independently in these soils in green house conditions and harvested after 125 days for measurement of growth, legume-microbe symbiosis, N nutrition and C growth costs. Results showed that the two legumes had different growth adaptations. Vachellia nilotica grown in control soils and +P soils nodulated with various Burkholderia spp., while L. leucocephala did not nodulate in all soil treatments. Both legumes utilized for growth both atmospheric- and soil-derived N across all treatments thereby decreasing C growth costs. Vachellia nilotica grown in +P soils accumulated the most biomass and N nutrition. Leucaena leucocephala maximized specific N assimilation rates by investing in below-ground biomass accumulation in control soils. This shows that L. leucocephala possesses traits that are successful in acquiring nutrients by investing in below-ground biomass and relying on utilization of N from both the soil and the atmosphere.

RevDate: 2022-06-24

van den Hurk AF, Skinner E, Ritchie SA, et al (2022)

The Emergence of Japanese Encephalitis Virus in Australia in 2022: Existing Knowledge of Mosquito Vectors.

Viruses, 14(6): pii:v14061208.

In early 2022, the Japanese encephalitis virus (JEV) was identified as the cause of stillborn and mummified piglets in pig farms in southeastern Australia. Human cases and additional pig farms with infected piglets were subsequently identified across a widespread area encompassing four states. To inform surveillance and control programs, we synthesized existing information on Australian vectors of JEV, much of which was generated in response to incursions of JEV into the northern state of Queensland between 1995 and 2005. Members of the Culex sitiens subgroup, particularly Culex annulirostris, should be considered the primary vectors of JEV in Australia, as they yielded >87% of field detections of JEV, were highly efficient laboratory vectors of the virus, readily fed on pigs and birds (the key amplifying hosts of the virus) when they were available, and are widespread and often occur in large populations. Three introduced species, Culex quinquefasciatus, Culex gelidus and Culex tritaeniorhynchus may also serve as vectors, but more information on their geographical distribution, abundance and bionomics in the Australian context is required. Mosquitoes from other genera, such as Aedes and Verrallina, whilst considered relatively poor vectors, could play a regional or supplemental role in transmission, especially facilitating vertical transmission as a virus overwintering mechanism. Additional factors that could impact JEV transmission, including mosquito survival, dispersal and genetics, are also discussed. Possible directions for investigation are provided, especially in the context of the virus emerging in a region with different mosquito fauna and environmental drivers than northern Australia.

RevDate: 2022-06-23

Montenegro-Hoyos AC, Muñoz-Carvajal EA, Wallberg BN, et al (2022)

Biodiversity in Times of COVID-19 and its Relationship with the Socio-Economic and Health Context: A Look from the Digital Media.

Environmental management [Epub ahead of print].

The COVID-19 pandemic has caused a pause in people's activities and a socio-economic crisis worldwide due to confinement. This situation is an unprecedented opportunity to understand how these changes may impact biodiversity and its conservation, as well as to study human-nature interaction. Biodiversity plays an essential role in conservation and economic activities, and in countries with greater inequality and low gross domestic product (GDP), biodiversity could have a low priority. Moreover, how biodiversity is prioritized in a society impacts how the citizens view it, and digital news tends to shape biodiversity narratives. The aim of this work was to determine the main trends in biodiversity-related news categories during the COVID-19 pandemic in countries with terrestrial and marine hotspots and relate them to the socioeconomic and public health context of each country. For this, we searched for news on biodiversity and Covid-19 in the first 6 months of the pandemic and related them to GDP, Gini-index, deaths, and infections by Covid-19. Results showed that conservation, public policies, and use of natural resources stood out as the main news categories across countries, with a positive narrative and mostly related to terrestrial rather than marine environments. On the other hand, the socio-economic and public health characteristics of each country had an influence on which aspect of the biodiversity was reflected in the media. For example, countries with greater inequality were associated with tourism news, additionally, countries with low GDP, high cases, and deaths by Covid-19 were associated with news about cultural diversity. In contrast, countries with high GDP and low inequality were associated with news about zoonosis, research and development, public policies, and alien and invasive species.

RevDate: 2022-06-24
CmpDate: 2022-06-24

Keen SC, Wackett AA, Willenbring JK, et al (2022)

Non-native species change the tune of tundra soils: Novel access to soundscapes of the Arctic earthworm invasion.

The Science of the total environment, 838(Pt 3):155976.

Over the last decade, an increasing number of studies have used soundscapes to address diverse ecological questions. Sound represents one of the few sources of information capable of providing in situ insights into processes occurring within opaque soil matrices. To date, the use of soundscapes for soil macrofauna monitoring has been experimentally tested only in controlled laboratory environments. Here we assess the validity of laboratory predictions and explore the use of soil soundscape proxies for monitoring soil macrofauna (i.e., earthworm) activities in an outdoor context. In a common garden experiment in northern Sweden, we constructed outdoor mesocosm plots (N = 36) containing two different Arctic vegetation types (meadow and heath) and introduced earthworms to half of these plots. Earthworms substantially altered the ambient soil soundscape under both vegetation types, as measured by both traditional soundscape indices and frequency band power levels, although their acoustic impacts were expressed differently in heath versus meadow soils. While these findings support the as-of-yet untapped promise of using belowground soundscape analyses to monitor soil ecosystem health, direct acoustic emissions from earthworm activities appear to be an unlikely proxy for tracking worm activities at daily timescales. Instead, earthworms indirectly altered the soil soundscape by 're-engineering' the soil matrix: an effect that was dependent on vegetation type. Our findings suggest that long-term (i.e., seasonal) earthworm activities in natural soil settings can likely be monitored indirectly via their impacts on soundscape measures and acoustic indices. Analyzing soil soundscapes may enable larger-scale monitoring of high-latitude soils and is directly applicable to the specific case of earthworm invasions within Arctic soils, which has recently been identified as a potential threat to the resilience of high-latitude ecosystems. Soil soundscapes could also offer a novel means to monitor soils and soil-plant-faunal interactions in situ across diverse pedogenic, agronomic, and ecological systems.

RevDate: 2022-06-23

Reinke BA, Cayuela H, Janzen FJ, et al (2022)

Diverse aging rates in ectothermic tetrapods provide insights for the evolution of aging and longevity.

Science (New York, N.Y.), 376(6600):1459-1466.

Comparative studies of mortality in the wild are necessary to understand the evolution of aging; yet, ectothermic tetrapods are underrepresented in this comparative landscape, despite their suitability for testing evolutionary hypotheses. We present a study of aging rates and longevity across wild tetrapod ectotherms, using data from 107 populations (77 species) of nonavian reptiles and amphibians. We test hypotheses of how thermoregulatory mode, environmental temperature, protective phenotypes, and pace of life history contribute to demographic aging. Controlling for phylogeny and body size, ectotherms display a higher diversity of aging rates compared with endotherms and include phylogenetically widespread evidence of negligible aging. Protective phenotypes and life-history strategies further explain macroevolutionary patterns of aging. Analyzing ectothermic tetrapods in a comparative context enhances our understanding of the evolution of aging.

RevDate: 2022-06-23

Ramadan MM, D Dailey (2022)

Trouble for Horses in Paradise: Toxicity and Fatality Resulting from the Consumption of Indigofera spicata (Fabaceae) on Oahu Island.

Veterinary sciences, 9(6): pii:vetsci9060271.

This is the first account of fatal toxicity in horses resulting from grazing on the pasture plant creeping indigo, Indigofera spicata, on the island of Oahu, in the Hawaiian Islands. A survey in the town of Waialua on the north shore of Oahu island indicated that creeping indigo is common and abundant on grazing lands during the rainy season and requires intensive chemical and physical control measures. Four pastures were surveyed where ranchers reported mortality of more than 17 horses since 2020. We document these incidents to alert state animal and livestock support officials, groups monitoring invasive species, and horse owners regarding the problem of this noxious weed and to support breeders with information to confront its invasiveness. Herbicide treatment is not economically feasible, and breeders opted to physically uproot the plants from the paddocks and restrain horses to clear pastures as they were eliminating the plants. We urge state officials for a long-term control strategy to reduce the problems associated with this weed.

RevDate: 2022-06-23

Barahona-Segovia RM, González CR, L Pañinao-Monsálvez (2022)

Citizen Science Meet South American Tachinids: New Records of Feather-Legged Fly Trichopoda (Galactomyia) pictipennis Bigot (Diptera: Tachinidae) from Chile.

Neotropical entomology [Epub ahead of print].

The species of Gymnosomatini (Diptera: Tachinidae) are specialized to attack stink bugs (Hemiptera: Pentatomidae). Some of these flies, such as those in the genus Trichopoda Berthold, are conspicuous and represent target species to study with citizen science. Here we report for the first time the distribution range of T. (Galactomyia) pictipennis Bigot, a newly introduced biological control species of tachinid for use against stink bugs in Chile using data obtained through the citizen science method. Additionally, we update the distribution of T. arcuata (Bigot), a native biological control species of tachinid, and assess the grade of overlap between the flies and their main stink bug hosts. We obtained data regarding the occurrence of flies and stink bugs from the citizen science program "Moscas Florícolas de Chile," from Facebook groups, and from iNaturalist. We standardized our data to avoid temporal, spatial, and geographic biases. We report the extent of occurrence (EOO) and area of occupancy (AOO) for each fly and stink bug species. The EOOs for T. pictipennis and T. arcuata are 85,474 km2 and 20,647 km2 through central Chile ecosystems, respectively. The EOO of T. arcuata is overlapped by 53% with the introduced species. Trichopoda pictipennis has a high percentage of overlap with the EOO of Nezara viridula Linnaeus (61%), whereas T. arcuata has low percentages of overlap with different native Acledra species and with N. viridula. We discuss the potential of citizen science to detect (1) areas with higher diversity or gaps of occurrences, (2) new biological control agents, (3) prey records, (4) negative impacts on non-target species, (5) changes in composition at long-term, and (6) areas to promote conservation biological control in agricultural landscapes.

RevDate: 2022-06-23

Crespo N, Louzada J, Fernandes LS, et al (2022)

Microscopic Identification of Anatomical Elements and Chemical Analysis of Secondary Nests of Vespa velutina nigrithorax du Buyson.

Insects, 13(6): pii:insects13060537.

Vespa velutina accidentally arrived in Europe (France) in 2004, and rapidly expanded throughout the entire country. Its presence in mainland Portugal was first noticed in 2011. Being an invasive species with no natural predators in the region to control it, it has caused enormous environmental and economic damage, particularly on Apis mellifera (honeybee) colonies. Although there is already some research on this species' biology, little is known about its adaption to European ecological conditions, specifically in terms of nest building. This type of hornet builds a primary nest in the spring to start a colony. During the summer, they build a secondary nest to develop the main colony. These secondary nests are ovoid-shaped and range in size from 18.7 cm to 45.0 cm in diameter and from 19.2 cm to 65.0 cm in length, attaining their highest development in late summer. The external appearance of these nests is characterized by alternating stripes that are beige and brown in color. The main objective of this study is to identify the composition and the origin of the materials that are used by Vespa velutina nigrithorax to build the outer envelope of these secondary nests. This information could be very interesting and will not only increase our knowledge on the biology of the species in regions far from its original area, but will also be relevant for the future implementation of new policies to control this invasive species by means biological control. Several samples were taken from each nest and were observed under different optical magnifying devices. In the second stage, their chemical composition was analyzed by X-ray diffraction (XRD) and scanning electron microscopy (SEM/EDS). It was noticed that almost all of the materials used in the nests' construction were lignocellulose from woody materials from both softwood (gymnosperm) and hardwood (angiosperm) forest species as well from leaves and small particles of agricultural origin (grasses). The beige strips were formed almost exclusively from woody softwood cells, while the brown strips were composed of hardwood cells, leaf tissues, and grasses. Chemically, it was noticed that this material mainly consisted of cellulose, with more than 99% being composed of C and O and very little mineral material from elements such as Na, Al, Si, K, and Ca. The achieved results allow us to state that in the construction of these secondary nests, these hornets only used organic materials that are then probably agglomerated through their mouths.

RevDate: 2022-06-23

McPherson C, Avanesyan A, WO Lamp (2022)

Diverse Host Plants of the First Instars of the Invasive Lycorma delicatula: Insights from eDNA Metabarcoding.

Insects, 13(6): pii:insects13060534.

Identification of host plants of the invasive spotted lanternfly, Lycorma delicatula (Hemiptera: Fulgoridae), has been the focus of many studies. While the adults and late nymphs are relatively easy to observe on plants and to use for molecular gut-content analysis, studying the early instars is more challenging. This study is the continuation of our ongoing efforts to determine the host range for each developmental stage of L. delicatula. In the present study, we focused exclusively on the first nymphal instars, and we used a novel approach, utilizing "bulk" DNA extracts for DNA metabarcoding of nymphal gut contents, to identify all the detectable plants that the nymphs had ingested prior to being collected. We were able to obtain high-quality amplicons (up to 406 bp) of a portion of the rbcL gene and detect 27 unique ingested plant species belonging to 17 families. Both native and introduced plants with the prevalence of trees and grasses were present among the ingested plants. We also identified 13 novel host plants that have not been previously reported for L. delicatula on the U.S. territory. The results from our study have important applications for developing effective programs on early monitoring of invasive L. delicatula.

RevDate: 2022-06-23

Guo KF, Peng XM, Tu JY, et al (2022)

Abnormal Antennal Olfactory Sensilla Phenotypes Involved in Olfactory Deficit in Bactrocera correcta (Diptera: Tephritidae).

Insects, 13(6): pii:insects13060535.

The guava fruit fly, Bactrocera correcta, is one of the most destructive pests in the genus Bactrocera and detects environmental odorants mainly through antennal olfactory sensilla phenotypes with nanopores. However, it is unclear whether there are naturally occurring abnormal antennal olfactory sensilla phenotypes that affect olfaction. Here, we found that there were abnormal bulges besides nanopores on the surface of trichoid and basiconic olfactory sensilla in the antennal flagellum of long-term laboratory rearing colony (LTC), and that nanopore number in these olfactory sensilla was also remarkably reduced. Notably, the electroantennogram (EAG) responses of LTC insects to methyl eugenol or β-caryophyllene were inhibited, and their behavioral responses elicited by the same odorants were also impaired. These results revealed naturally occurring abnormal antennal olfactory sensilla phenotypes which were involved in olfactory deficit in B. correcta, providing a platform to further study nanopore-targeted pest control technologies in the future.

RevDate: 2022-06-23

Rondoni G, Chierici E, Marchetti E, et al (2022)

Improved Captures of the Invasive Brown Marmorated Stink Bug, Halyomorpha halys, Using a Novel Multimodal Trap.

Insects, 13(6): pii:insects13060527.

Capture strategies for the brown marmorated stink bug, Halyomorpha halys (Hemiptera: Pentatomidae), are challenging. Here we developed and evaluated a multimodal trap which combines visual and olfactory stimuli. Visual stimuli consisted of LEDs emitting UV-A and visible light. Olfactory stimuli were comprised of the synthetic aggregation pheromone and odours from trapped H. halys individuals. Stink bug attraction at different wavelengths was evaluated in laboratory two-choice bioassays, and different prototypes of the trap were tested in 2021 in natural, agricultural, and urban settings. Traps with a combination of UV-A and blue or green visible wavelengths provided higher H. halys attraction (up to ~8-fold) compared to traditional sticky or small pyramidal traps. The concurrent presence of synthetic pheromone and LED had a synergistic effect on H. halys positive phototaxis. Further development and implementation of the multimodal trap is discussed for prospective use in attract-and-kill or push-pull strategies.

RevDate: 2022-06-23

Simeonova R, Shkondrov A, Kozuharova E, et al (2022)

A Study on the Safety and Effects of Amorpha fruticosa Fruit Extract on Spontaneously Hypertensive Rats with Induced Type 2 Diabetes.

Current issues in molecular biology, 44(6):2583-2592 pii:cimb44060176.

Metabolic syndrome is characterized by a variety of diagnostic criteria: obesity, dyslipidemia, type 2 diabetes, and arterial hypertension. They contribute to the elevated risk of cardiovascular morbidity and mortality. The potential for Amorpha fruticosa L. (Fabaceae) to improve diabetes and metabolic disease is promising, based on in vitro tests. This is why a further investigation of the species is needed. Additionally, a toxicity review in relation to safety revealed that to date, there are no published data regarding the toxicity of A. fruticosa towards humans. This species could provide abundant and cheap resources because it is an aggressive invasive plant that grows almost unrestrictedly. The objective of this study was to evaluate the acute toxicity of a purified extract of A. fruticosa (EAF), and to assess its antioxidant, antihypertensive, and antihyperglycemic activity in streptozotocin-induced diabetic spontaneously hypertensive rats (SHRs). The EAF was slightly toxic (LD50 = 2121 mg/kg, b.w.) when administered orally, and moderately toxic (LD50 = 316 mg/kg, b.w.) at intraperitoneal administration, both in mice. The oral administration of EAF (100 mg/kg) for 35 days to SHRs caused significant decreases in the systolic pressure, blood glucose levels, and MDA quantity. It also increased the hepatic level of the endogenous antioxidant GSH, not only in diabetic SHRs, but also in the control group. An additional potential benefit to human health might be conferred through the environmental management of A. fruticosa based on its large-scale use for medicinal purposes, as this aggressive invasive species brings problems to natural habitats in many European countries.

RevDate: 2022-06-23

Bathia J, Schröder K, Fraune S, et al (2022)

Symbiotic Algae of Hydra viridissima Play a Key Role in Maintaining Homeostatic Bacterial Colonization.

Frontiers in microbiology, 13:869666.

The freshwater polyp Hydra viridissima (H. viridissima) harbors endosymbiotic Chlorella algae in addition to a species-specific microbiome. The molecular basis of the symbiosis between Hydra and Chlorella has been characterized to be metabolic in nature. Here, we studied the interaction between the extracellularly located microbiota and the algal photobiont, which resides in Hydra's endodermal epithelium, with main focus on Legionella bacterium. We aimed at evaluating the influence of the symbiotic algae on microbial colonization and in shaping the host microbiome. We report that the microbiome composition of symbiotic and aposymbiotic (algae free) H. viridissima is significantly different and dominated by Legionella spp. Hvir in aposymbiotic animals. Co-cultivation of these animals resulted in horizontal transmission of Legionella spp. Hvir bacteria from aposymbiotic to symbiotic animals. Acquisition of this bacterium increased the release of algae into ambient water. From there, algae could subsequently be taken up again by the aposymbiotic animals. The presence of algal symbionts had negative impact on Legionella spp. Hvir and resulted in a decrease of the relative abundance of this bacterium. Prolonged co-cultivation ultimately resulted in the disappearance of the Legionella spp. Hvir bacterium from the Hydra tissue. Our observations suggest an important role of the photobiont in controlling an invasive species in a metacommunity and, thereby, shaping the microbiome.

RevDate: 2022-06-23
CmpDate: 2022-06-23

Wang YF, Liu ZY, Zhang BG, et al (2022)

[Effects of the removal of invasive Moso bamboo on soil microbial biomass and enzyme activities in subtropical forests].

Ying yong sheng tai xue bao = The journal of applied ecology, 33(5):1233-1239.

Removal of invasive plant species is the first step to restoring the invaded ecosystems. The soil microbial biomass and extracellular enzyme activities were measured in Moso bamboo (Phyllostachys edulis) pure forest (completely invasion), invasive P. edulis removal forest (secondary succession 5 years after clear cutting), and the evergreen broadleaved forest (no invasion) in Tianmu Mountain. The results showed that compared with P. edulis pure forest, invasive P. edulis removal significantly increased the contents of soil organic carbon (SOC), nitrate nitrogen, available phosphorus and potassium, as well as microbial biomass carbon (MBC) and microbial biomass phosphorus (MBP), while significantly decreased microbial biomass nitrogen (MBN). The activities of α-glucosidase (AG), β-glucosidase (BG), leucine aminopeptidase (LAP) and phenol oxidase (POX) in the forest with removal of invasive P. edulis were significantly higher than those in P. edulis pure forest, while invasive P. edulis removal did not change the activities of cellodisaccharide hydrolase (CBH), β-N-acetyl-glucosaminopeptidase (NAG), acid phosphatase (ACP) and peroxidase (PER). Furthermore, the activities of AG, BG and LAP were positively correlated with SOC and MBC, while the increase in POX activity was positively correlated with soil nitrate content. In addition, MBC, MBN and MBP, and activities of AG, BG, NAG, LAP and ACP in P. edulis removal forest forest were significantly higher than those in evergreen broadleaved forests. Taken together, the removal of invasive P. edulis could increase soil nutrient contents, microbial biomass and extracellular enzyme activities, thus could be considered as an effective way to restore the invaded forests. Our results provide important theoretical basis for controlling P. edulis invasion in subtropical forests.

RevDate: 2022-06-23
CmpDate: 2022-06-23

Qin HR, Guo WF, Wang W, et al (2022)

[Effects of Agasicles hygrophila herbivory on the clonal integration of Alternanthera philoxeroides and A. sessilis].

Ying yong sheng tai xue bao = The journal of applied ecology, 33(6):1661-1668.

Many alien invasive plants were clonal species. Examining the relationship between clonal integration characteristics and invasiveness of alien clonal plants is important for clarifying their ecological adaptability and invasion mechanisms. Here, with the invasive plant species Alternanthera philoxeroides and its native congener A. sessilis as the studying objects, we compared the effects of clonal integration on the growth and the biomass allocation of the apical ramets, basal ramets, and the whole fragment of both species under herbivory by the biocontrol beetle Agasicles hygrophila. The results showed that under herbivory by A. hygrophila, leaf number, stolon length, and ramet number of the apical ramets as well as the ground diameter of the whole fragment of A. philoxeroides were significantly higher under clonal integration treatment compared to that without clonal integration, whereas belowground biomass and total biomass of the basal ramets and the whole fragment of A. philoxeroides were conversely decreased by 78.2%, 60.9 % and 48.7%, 37.2%, respectively, under clonal integration treatment compared to that without clonal integration. Ground diameter of the apical ramets and leaf number of the whole fragment of A. sessilis were significantly higher, but the number of basal ramets was 21.7% lower under clonal integration treatment compared to that without clonal integration. The biomass of the apical ramets, basal ramets, and whole fragment of A. sessilis did not significantly differ between clonal integration and without clonal integration treatments. The results of cost-benefit analysis showed that the ramet number and biomass of the apical ramets of A. philoxeroides as well as the ramet number of the apical ramets of A. sessilis were significantly benefited from clonal integration, but the cost-benefit of the ramet number and biomass of the basal ramets of both species were not affected by clonal integration treatment. These results suggested that clonal integration could partly alleviate herbivory pressure by A. hygrophila on the apical ramets of both species, and that the clonal integration ability of A. philoxeroides was stronger than A. sessilis. However, both species seemed not able to gain significant benefits from cloning integration at the whole fragment level.

RevDate: 2022-06-22

Poli C, Robertson EP, Martin J, et al (2022)

An invasive prey provides long-lasting silver spoon effects for an endangered predator.

Proceedings. Biological sciences, 289(1977):20220820.

The natal environment can have long-term fitness consequences for individuals, particularly via 'silver spoon' or 'environmental matching' effects. Invasive species could alter natal effects on native species by changing species interactions, but this potential remains unknown. Using 17 years of data on 2588 individuals across the entire US breeding range of the endangered snail kite (Rostrhamus sociabilis), a wetland raptor that feeds entirely on Pomacea snails, we tested for silver spoon and environmental matching effects on survival and movement and whether the invasion of a non-native snail may alter outcomes. We found support for silver spoon effects, not environmental matching, on survival that operated through body condition at fledging, explained by hydrology in the natal wetland. When non-native snails were present at the natal site, kites were in better condition, individual condition was less sensitive to hydrology, and kites fledged across a wider range of hydrologic conditions, leading to higher survival that persisted for at least 10 years. Movement between wetlands was driven by the current (adult) environment, and birds born in both invaded and uninvaded wetlands preferred to occupy invaded wetlands post-fledging. These results illustrate that species invasions may profoundly impact the role of natal environments on native species.

RevDate: 2022-06-22

Kennedy S, Calaor J, Zurápiti Y, et al (2022)

Richness and resilience in the Pacific: DNA metabarcoding enables parallelized evaluation of biogeographic patterns.

Molecular ecology [Epub ahead of print].

Islands make up a large proportion of Earth's biodiversity, yet are also some of the most sensitive systems to environmental perturbation. Biogeographic theory predicts that geologic age, area, and isolation typically drive islands' diversity patterns, and thus potentially impact non-native spread and community homogenization across island systems. One limitation in testing such predictions has been the difficulty of performing comprehensive inventories of island biotas and distinguishing native from introduced taxa. Here, we use DNA metabarcoding and statistical modeling as a high throughput method to survey community-wide arthropod richness, the proportion of native and non-native species, and the incursion of non-natives into primary habitats on three archipelagos in the Pacific - the Ryukyus, the Marianas and Hawaii - which vary in age, isolation and area. Diversity patterns largely match expectations based on island biogeography theory, with the oldest and most geographically connected archipelago, the Ryukyus, showing the highest taxonomic richness and lowest proportion of introduced species. Moreover, we find evidence that forest habitats are more resilient to incursions of non-natives in the Ryukyus than in the less taxonomically rich archipelagos. Surprisingly, we do not find evidence for biotic homogenization across these three archipelagos: the assemblage of non-native species on each island is highly distinct. Our study demonstrates the potential of DNA metabarcoding to facilitate rapid estimation of biogeographic patterns, the spread of non-native species, and the resilience of ecosystems.

RevDate: 2022-06-21

Milardi M, Iemma A, Waite IR, et al (2022)

Natural and anthropogenic factors drive large-scale freshwater fish invasions.

Scientific reports, 12(1):10465.

We analyzed the large-scale drivers of biological invasions using freshwater fish in a Mediterranean country as a test case, and considering the contribution of single species to the overall invasion pattern. Using Boosted Regression Tree (BRT) models, variation partitioning and Redundancy Analysis (RDA), we found that human factors (especially eutrophication) and climate (especially temperature) were significant drivers of overall invasion. Geography was also relevant in BRT and RDA analysis, both at the overall invasion and the single species level. Only variation partitioning suggested that land use was the second most significant driver group, with considerable overlap between different invasion drivers and only land use and human factors standing out for single effects. There was general accordance both between different analyses, and between invasion outcomes at the overall and the species level, as most invasive species share similar ecological traits and prefer lowland river stretches. Human-mediated eutrophication was the most relevant invasion driver, but the role of geography and climate was at least equally important in explaining freshwater fish invasions. Overall, human factors were less prominent than natural factors in driving the spread and prevalence of invasion, and the species spearheading it.

RevDate: 2022-06-21

Walczyk AM, EI Hersch-Green (2022)

Do water and soil nutrient scarcities differentially impact the performance of diploid and tetraploid Solidago gigantea (Giant Goldenrod, Asteraceae)?.

Plant biology (Stuttgart, Germany) [Epub ahead of print].

RATIONALE: Plants require water and nutrients for survival, although the effects of their availabilities on plant fitness differs amongst species. Genome size variation, within and across species, is suspected to influence plant water and nutrient requirements, but little is known about how variations in these resources concurrently affect plant fitness based on genome size. We examined how genome size variation between autopolyploid cytotypes influences plant morphological and physiological traits, and whether cytotype-specific trait responses differ based on water and/or nutrient availability.

METHODS: Diploid and autotetraploid Solidago gigantea (Giant Goldenrod) were grown in a greenhouse under four soil water:nitrogen+phosphorus treatments (L:L, L:H, H:L, H:H), and stomata characteristics (size, density), growth (above- and belowground biomass, root/shoot ratio), and physiological (net photosynthetic capacity, transpiration rates, water use efficiency) responses were measured.

KEY RESULTS: Resource availabilities and cytotype identity influenced some plant responses but their effects were independent of each other. Plants grown in high-water and nutrient treatments were larger, plants grown in low-water or high-nutrient treatments had higher water use efficiency but lower transpiration rates, and photosynthesis and transpiration rates decreased as plants aged. Autotetraploids also had larger and fewer stomata, greater biomass, and greater photosynthetic capacity than diploids.

CONCLUSIONS: Nutrient and water availability could influence intra- and interspecific competitive outcomes. Although S. gigantea cytotypes were not differentially affected by resource treatments, genome size may influence cytogeographic range patterning and population establishment likelihood. For instance, the greater size of autotetraploid S. gigantea might render them more competitive for resources and niche space than diploids.

RevDate: 2022-06-20

Prajapati J, Singh A, Patil K, et al (2022)

An occurrence data set for invasive and naturalized alien plants in India.

Ecology [Epub ahead of print].

India has numerous invasive alien plant species (IAPS), which seriously impact biodiversity, ecosystem services, and economic development. Availability of reliable occurrence records of the IAPS is of great importance for their successful management, prediction of distribution across time and space, and other research and development efforts. Global databases of occurrence data, like the Global Biodiversity Information Facility (GBIF), are often not exhaustive, especially for India, and poorly represent the actual distribution of the IAPS in the country. Our objectives to create this data set were three folds: 1) to compile occurrence data for the invasive and naturalized alien plant species of India, 2) to have the spatial and temporal information associated with the occurrence records, and 3) to share the data in an accessible format, so every record is traceable to its sources, and allow users to submit data to increase the resolution of the data set. To achieve these objectives, we extracted data from 3137 literature records and 357 herbarium sheets. For each occurrence record, we curated information for 20 variables, which were arranged in a table with the Darwin Core (DwC) terms as column names. All data were undergone technical validation before including them in the database. A total of 12,347 occurrence records were obtained for 362 species (195 invasive aliens and 167 naturalized aliens). The number of collected occurrence records was much higher for the invasive aliens (73.7%) than for the naturalized alien species (26.3%). Our data set will supplement the GBIF data by 60.39%, and occurrence records will be added for 64 invasive and naturalized alien plant species. The data set, as a part of the larger database of the Indian Alien Flora Information (ILORA) database, is made available without any restriction of use, given this data paper is properly cited. We have also made provisions for users to submit occurrence-related data following a data standard. The users are encouraged to cite the original reference when using a specific data record. The data set is expected to assist a wide range of stakeholders involved in India's scientific research, policy formulation, and decision-making related to IAPS.

RevDate: 2022-06-20

Yan Z, Wu L, Lv T, et al (2022)

Response of spatio-temporal changes in sediment phosphorus fractions to vegetation restoration in the degraded river-lake ecotone.

Environmental pollution (Barking, Essex : 1987) pii:S0269-7491(22)00864-8 [Epub ahead of print].

Phosphorus (P) is an essential element in the ecosystem and the cause of the eutrophication of rivers and lakes. The river-lake ecotone is the ecological buffer zone between rivers and lakes, which can transfer energy and material between terrestrial and aquatic ecosystems. Vegetation restoration of degraded river-lake ecotone can improve the interception capacity of P pollution. However, the effects of different vegetation restoration types on sediment P cycling and its mechanism remain unclear. Therefore, we seasonally measured the P fractions and physicochemical properties of sediments from different restored vegetation (three native species and one invasive species). The results found that vegetation restoration significantly increased the sediment total P and bioavailable P content, which increased the sediment tolerance to P pollution in river-lake ecotone. In addition, the total P content in sediments was highest in summer and autumn, but lower in spring and winter. The total P and bioavailable P contents in surface sediments were the highest. They decreased with increasing depth, suggesting that sediment P assimilation by vegetation restoration and the resulting litter leads to redistribution of P in different seasons and sediment depths. Microbial biomass-P (MBP), total nitrogen (TN), and sediment organic matter (SOM) are the main factors affecting the change of sediment phosphorus fractions. All four plants' maximum biomass and P storage appeared in the autumn. Although the biomass and P storage of the invasive species Alternanthera philoxeroides were lower, the higher bioavailable P content and MBP values of the surface sediments indicated the utilization efficiency of sediment resources. These results suggest that vegetation restoration affects the distribution and circulation of P in river and lake ecosystems, which further enhances the ecological function of the river-lake ecotone and prevents the eutrophication and erosion of water and sediment in the river-lake ecotone.

RevDate: 2022-06-20

Ilyas M, Shah S, Lai YW, et al (2022)

Leaf Functional Traits of Invasive Grasses Conferring High-Cadmium Adaptation Over Natives.

Frontiers in plant science, 13:869072.

Heavy metal (HM) contamination resulting from industrialization and urbanization during the Anthropocene along with plant invasion can severely threaten the growth and adaptation of local flora. Invasive alien plant species generally exhibit a growth pattern consistent with their functional traits in non-contaminated environments in the introduced range. However, it remains unclear whether invasive alien plants have an advantage over native plants in contaminated environments and whether this growth pattern is dependent on the adaptation of their leaf functional traits. Here, we selected two congeneric pairs of invasive alien and native grasses that naturally co-exist in China and are commonly found growing in contaminated soil. To evaluate the effect of cadmium (Cd) on the structural and physiological leaf traits, we grew all four species in soil contaminated without or with 80 mg/kg Cd. Invasive plants contained significantly higher concentrations of Cd in all three organs (leaf, stem, and root). They displayed a higher transfer factor and bioconcentration factor (BCF) of shoot and root than natives, indicating that invasive species are potential Cd hyperaccumulators. Invasive plants accumulated polyphenol oxidase (PPO) to higher levels than natives and showed similar patterns of leaf structural and physiological traits in response to changes in Cd bioconcentration. The quantifiable leaf structural traits of invasive plants were significantly greater (except for stomatal density and number of dead leaves) than native plants. Leaf physiological traits, chlorophyll content, and flavonoid content were also significantly higher in invasive plants than in natives under Cd stress conditions after 4 weeks, although nitrogen balance index (NBI) showed no significant difference between the two species. Chlorophyll fluorescence parameters decreased, except for the quantum yield of photosystem II (ΦPSII) and the proportion of open photosystem II (qP), which increased under Cd stress conditions in both species. However, invasive plants exhibited higher fluorescence parameters than natives under Cd stress, and the decrement observed in invasive plants under Cd stress was greater than that in natives. High Cd adaptation of invasive grasses over natives suggests that invasive plants possess optimal leaf structural and physiological traits, which enable them to adapt to stressful conditions and capture resources more quickly than natives. This study further emphasizes the potential invasion of alien plants in contaminated soil environments within the introduced range. To a certain extent, some non-invasive alien plants might adapt to metalliferous environments and serve as hyperaccumulator candidates in phytoremediation projects in contaminated environments.

RevDate: 2022-06-18

Deeley B, N Petrovskaya (2022)

Propagation of invasive plant species in the presence of a road.

Journal of theoretical biology pii:S0022-5193(22)00194-1 [Epub ahead of print].

Invasive plant species pose a significant threat to biodiversity and the economy, yet their management is often resource-intensive and expensive, and further research is required to make control measures more efficient. Evidence suggests that roads can have an important effect on the spread of invasive plant species, although little is known about the underlying mechanisms at play. We have developed a novel mathematical model to analyse the impact of roads on the propagation of invasive plants. The integro-difference equation model is formulated for stage-structured population and incorporates a road sub-domain in the spatial domain. The results of our study reveal, that, depending on the definition of the growth function in the model, there are three distinct types of behaviour in front of the road. Roads can act as barriers to invasion, lead to a formation of a beachhead in front of the road, or act as corridors allowing the invasive species to invade the domain in front of the road. Analytical and computational findings on how roads can impact the spread of invasive species show that a small change in conditions of the environment favouring the invasive species can change the case for the road, allowing the invasive species to invade the domain in front of the road where it previously could not spread.

RevDate: 2022-06-18

Gillard MB, Castillo JM, Mesgaran MB, et al (2022)

Germination niche breadth of invasive Iris pseudacorus (L.) suggests continued recruitment from seeds with climate warming.

American journal of botany [Epub ahead of print].

PREMISE: Understanding recruitment processes of invasive species is central to conservation and management strategies. Iris pseudacorus, an emergent macrophyte, has established invasive populations across a broad global range and reduces biodiversity in wetland ecosystems. Climate warming is altering germination cues, yet studies on the invasion of wetland macrophytes often ignore germination ecology despite its importance to their establishment and spread.

METHODS: We explored germination of seeds from invasive I. pseudacorus populations in California in response to seed coat presence or absence, and several environmental factors. Using experimental results in a thermal time model, we derived germination temperature thresholds.

RESULTS: Germination of I. pseudacorus seeds did not require cold or warm stratification, and was not impacted by seed coat presence or absence. Germination occurred in the dark, although germinability was two to three-fold times greater under light. At constant temperature, thermal time model estimates included: 18.3 ± 1.8 °C base germination temperature (T b); 28.2 ± 0.5 °C optimal temperature (T o); 41.0 ± 1.7 °C ceiling temperature (T c). Seeds exposed to 36.0 °C achieved over 10% germination, and embryos of ungerminated seeds presented 76% viability. Overall, germinability remained relatively low at constant temperatures (≤ 25%) but was close to 90% under alternating daily temperatures.

CONCLUSIONS: Exposure to diurnally fluctuating temperatures is essential for this species to achieve high germination rates. Our study reveals that I. pseudacorus has a broad germination niche supporting its establishment in a relatively wide range of environments, including at high temperatures more frequent with climate change. This article is protected by copyright. All rights reserved.

RevDate: 2022-06-18

Martínez-Hernández F, Villalobos G, Montañez-Valdez OD, et al (2022)

A New Record of the Introduced Species Triatoma infestans (Hemiptera: Reduviidae) in Mexico.

Journal of medical entomology pii:6610969 [Epub ahead of print].

Here, we report a new record of Triatoma infestans (Klug) in Mexico after 50 years and provide a brief description of the discovery area. Fifty-nine specimens (71.2% adults) of the introduced species were collected from the peridomestic areas of a single house in the port of Manzanillo in the state of Colima, Mexico. Thirty-one specimens (52.5%) were collected from the exterior walls of the house and were apparently attracted to light. The other specimens (47.5%) were associated with chickens. No specimen was infected with Trypanosoma cruzi Chagas, the causative agent of Chagas disease, possibly because they were feeding on chickens. We speculate that the introduced species travelled from South America to Mexico via seed shipment in a twenty-foot equivalent unit (TEU) maritime container. Because Mexican phytosanitary regulations demand only the cargo to be inspected, the triatomines could have escaped notice during inspection. Subsequently, as the cargo was unloaded and the TEU was stored, the triatomines likely flew to and invaded the nearby residential areas. The rediscovery of this domestic vector of T. cruzi in Mexico warrants further investigation owing to the potential risk of transmission to the inhabitants of the study area.

RevDate: 2022-06-17

Rothman SB, Diamant A, M Goren (2022)

Under the radar: co-introduced monogeneans (Polyopisthocotylea: Gastrocotylinea) of the invasive fish Scomberomorus commerson in the Mediterranean Sea.

Parasitology research [Epub ahead of print].

The Levant Basin is in many ways the world's most invaded marine ecosystem owing to the existence of the man-made Suez Canal. The invasion of free-living organisms through this pathway is increasingly documented and monitored in the past two decades, and their ecological impact recognized. Nonetheless, while tremendous scientific effort is invested in documenting introduced fishes, co-introduction events of these fishes and their parasites have drawn relatively little interest. In our research, we examined the presence of gill parasites (Monogenea) on the invasive narrow barred Spanish mackerel Scomberomorus commerson which has been known in the Mediterranean Sea for 80 years. The gills of S. commerson supported numerous, relatively large monogeneans (Monogenea: Gastrocotylinea), reaching prevalence levels of 100% with a mean intensity of ~ 80 worms per host. Using an integrated molecular and morphological approach, four gastrocotylinean species were identified: Gotocotyla acanthura, Cathucotyle cathuaui, Pricea multae, and Pseudothoracocotyla ovalis. Two species, C. cathuaui and P. ovalis, are reported here for the first time from the Mediterranean. Sequences of the 28S rRNA gene of G. acanthura from native hosts, Pomatomus saltatrix and Trachinotus ovatus, differed from individuals collected from S. commerson by 1.8%. We therefore suggest that the taxonomic status and distribution of G. acanthura should be revisited, and we recommend an integrated approach as essential to accurately detect co-introductions.

RevDate: 2022-06-17

Li F, Liu X, Zhu J, et al (2022)

The Role of Genetic Factors in the Differential Invasion Success of Two Spartina Species in China.

Frontiers in plant science, 13:909429.

Biological invasions have become one of the greatest threats to global biodiversity and ecosystem conservation. Most previous studies have revealed how successful invasive species adapt to new environments and climate change through phenotypic and genetic evolution. Some researchers suggested that understanding unsuccessful or less successful biological invasions might be important for understanding the relationships between invasion adaptability and climate factors. We compared the sexual reproduction ability, genetic diversity, and gene × environment interaction in two intentionally introduced alien species in China (Spartina anglica and Spartina alterniflora) based on restriction site-associated DNA (RAD) sequencing. After more than 50 years, the distribution of S. alterniflora has rapidly expanded, while S. anglica has experienced extreme dieback. A total of 212,939 single nucleotide polymorphisms (SNPs) for the two Spartina species were used for analysis. The multilocus genotype (MLG) analysis revealed that clonal reproduction was the prevalent mode of reproduction in both species, indicating that a change in the mode of reproduction was not the key factor enabling successful invasion by Spartina. All genetic diversity indicators (He, Ho, π) in S. alterniflora populations were at least two times higher than those in S. anglica populations, respectively (p < 0.001). Furthermore, the population genetic structure and stronger patterns of climate-associated loci provided support for rapid adaptive evolution in the populations of S. alterniflora in China. Altogether, our results highlight the importance of genetic diversity and local adaptation, which were driven by multiple source populations, in increasing the invasiveness of S. alterniflora.

RevDate: 2022-06-17

Vujanović D, Losapio G, Milić S, et al (2022)

The Impact of Multiple Species Invasion on Soil and Plant Communities Increases With Invasive Species Co-occurrence.

Frontiers in plant science, 13:875824.

Despite increasing evidence indicating that invasive species are harming biodiversity, ecological systems and processes, impacts of multiple species invasion and their links with changes in plant and soil communities are inadequately documented and remain poorly understood. Addressing multiple invaders would help to ward against community-wide, synergistic effects, aiding in designing more effective control strategies. In this work, correlative relationships are examined for potential impacts of three co-occurring invasive plant species, Amorpha fruticosa, Fraxinus pennsylvanica, and Acer negundo, on soil conditions and native plant diversity. The research was conducted in riparian ecosystems and included the following treatments: (1) co-occurrence of the three invasive plant species, (2) occurrence of a single invasive species, and (3) control, i.e., absence of invasive species. Co-occurrence of three invasive plant species caused higher direct impact on soil properties, soil functioning, and native plant diversity. Soil in mixed plots (those populated with all three invaders) contained higher levels of nitrifying bacteria, organic matter, nitrogen, and carbon as well as lower carbon to nitrogen ratio as compared to single species invaded plots and control plots. Furthermore, native plant diversity decreased with invasive plants co-occurrence. Differences in soil conditions and lower native plant diversity revealed the interactive potential of multiple invasive species in depleting biodiversity and eroding soil functionality, ultimately affecting ecological and biogeochemical processes both below and above ground. Our results highlight the need to prevent the impact of multispecies invasion, suggesting that riparian ecosystems affected by co-occurring invaders should be prioritized for invasion monitoring and ecological restoration.

RevDate: 2022-06-17

Caven AJ, JD Wiese (2022)

Reinventory of the vascular plants of Mormon Island Crane Meadows after forty years of restoration, invasion, and climate change.

Heliyon, 8(6):e09640 pii:S2405-8440(22)00928-8.

The majority of tallgrass prairie has been lost from North America's Great Plains, but remaining tracts often support significant biodiversity. Despite permanent protections for some remnants, they continue to face anthropogenic threats including habitat fragmentation, invasive species, and climate change. Conservationists have sought to buffer remnants from threats using prairie restoration but limited research has assessed such practices at the landscape-level. We reexamine the flora of Mormon Island, the largest tract of lowland tallgrass prairie remaining in the Central Platte River Valley (CPRV) of Nebraska, USA, nearly 40-years after it was initially inventoried and following widespread restoration. We also conducted preliminary inventories of nearby Shoemaker Island and adjacent off-island habitats using an ecotope-based stratified random sampling approach. We examined change at Mormon Island between 1980-1981 and 2015-2020 and compared it to adjacent conservation lands using a number of vegetation indices. We documented 389 vascular plant species on Mormon Island, 405 on Shoemaker Island, and 337 on off-island habitats from 2015-2020, which represented an increase in native and exotic species richness on Mormon Island compared to 1980-1981 results. Floristic quality index (FQI) values increased at Mormon Island between 1980-1981 and 2015-2020. Paradoxically, the distribution of exotic-invasive species also expanded. Mormon Island from 2015-2020 was more similar to Shoemaker Island and off-island habitats from 2015-2020 than Mormon Island from 1980-1981. Widespread restoration introduced a number of high conservation value species native to Nebraska but novel to the CPRV, which improved FQIs despite increased exotic species invasion. These concurrent trends appear to have driven biological homogenization across the study area. Restoration did not fully buffer Mormon Island from exotic species invasion but it may have partially mitigated the impact considering the persistence of most native species across a 40-year period. We recommend using "local ecotype" seed for restorations to preserve distinctive local communities.

RevDate: 2022-06-20
CmpDate: 2022-06-20

Castro-Cubillos ML, Taylor JD, Mastretta-Yanes A, et al (2022)

Monitoring of benthic eukaryotic communities in two tropical coastal lagoons through eDNA metabarcoding: a spatial and temporal approximation.

Scientific reports, 12(1):10089.

Tropical coastal lagoons are important ecosystems that support high levels of biodiversity and provide several goods and services. Monitoring of benthic biodiversity and detection of harmful or invasive species is crucial, particularly in relation to seasonal and spatial variation of environmental conditions. In this study, eDNA metabarcoding was used in two tropical coastal lagoons, Chacahua (CH) and Corralero (C) (Southern Mexican Pacific), to describe the benthic biodiversity and its spatial-temporal dynamics. The distribution of benthic diversity within the lagoons showed a very particular pattern evidencing a transition from freshwater to seawater. Although the two lagoon systems are similar in terms of the species composition of metazoans and microeukaryotes, our findings indicate that they are different in taxa richness and structure, resulting in regional partitioning of the diversity with salinity as the driving factor of community composition in CH. Harmful, invasive, non-indigenous species, bioindicators and species of commercial importance were detected, demonstrating the reach of this technique for biodiversity monitoring along with the continued efforts of building species reference libraries.

RevDate: 2022-06-17
CmpDate: 2022-06-17

Aguilera Flores MM, Medellín Castillo NA, Ávila Vázquez V, et al (2022)

Evaluation of a biocoagulant from devilfish invasive species for the removal of contaminants in ceramic industry wastewater.

Scientific reports, 12(1):9917.

This study evaluated the effectiveness of a biocoagulant produced from the devilfish invasive species and its combination with two chemical coagulants (aluminum sulfate and ferric sulfate) to remove turbidity, chemical oxygen demand, and total suspended solids in ceramic industry wastewater using a combined experimental design of Mixture-Process. This design optimized the coagulation process and evaluated the effects and interactions between mixture components and coagulant doses. An analysis of variance was used to analyze the experimental data obtained in the study, and the response surface plots by response type (turbidity, chemical oxygen demand, and total suspended solids) were obtained. Results showed that the coagulation treatment could be technically and economically feasible since efficiencies of turbidity, chemical oxygen demand, and total suspended solids removal of 74, 79, and 94% could be achieved using an optimal coagulant dose of 800 mg/L with a mixture of 35% biocoagulant and 65% ferric sulfate. Analysis of variance results showed that the models are significant, and the lack of fit is not required according to the probability value (p value), which were < 0.0001, and > 0.05, respectively. Hence, the experimental data were fitted to a combined reduced special cubic x linear model. These results support the use of devilfish meal as a biocoagulant, being more feasible in dual systems when mixed with ferric sulfate.

RevDate: 2022-06-17
CmpDate: 2022-06-17

Theurich N, Briski E, RN Cuthbert (2022)

Predicting ecological impacts of the invasive brush-clawed shore crab under environmental change.

Scientific reports, 12(1):9988.

Globally, the number of invasive non-indigenous species is continually rising, representing a major driver of biodiversity declines and a growing socio-economic burden. Hemigrapsus takanoi, the Japanese brush-clawed shore crab, is a highly successful invader in European seas. However, the ecological consequences of this invasion have remained unexamined under environmental changes-such as climatic warming and desalination, which are projected in the Baltic Sea-impeding impact prediction and management. Recently, the comparative functional response (resource use across resource densities) has been pioneered as a reliable approach to quantify and predict the ecological impacts of invasive non-indigenous species under environmental contexts. This study investigated the functional response of H. takanoi factorially between different crab sexes and under environmental conditions predicted for the Baltic Sea in the contexts of climate warming (16 and 22 °C) and desalination (15 and 10), towards blue mussel Mytilus edulis prey provided at different densities. Hemigrapsus takanoi displayed a potentially population-destabilising Type II functional response (i.e. inversely-density dependent) towards mussel prey under all environmental conditions, characterised by high feeding rates at low prey densities that could extirpate prey populations-notwithstanding high in-field abundances of M. edulis. Males exhibited higher feeding rates than females under all environmental conditions. Higher temperatures reduced the feeding rate of male H. takanoi, but did not affect the feeding rate of females. Salinity did not have a clear effect on feeding rates for either sex. These results provide insights into interactions between biological invasions and climate change, with future warming potentially lessening the impacts of this rapidly spreading marine invader, depending on the underlying population demographics and abundances.

RevDate: 2022-06-20
CmpDate: 2022-06-20

Hernández-Triana LM, Folly AJ, Sewgobind S, et al (2022)

Susceptibility of Aedes albopictus and Culex quinquefasciatus to Japanese encephalitis virus.

Parasites & vectors, 15(1):210.

BACKGROUND: Japanese encephalitis virus (JEV) is the principal cause of mosquito-borne encephalitis in human populations within Asia. If introduced into new geographic areas, it could have further implications for public and animal health. However, potential mosquito vectors for virus transmission have not been fully investigated. The Asian tiger mosquito, Aedes albopictus, has emerged in Europe and is now expanding its geographical range into more northerly latitudes. Culex quinquefasciatus, although absent from Europe, has been detected in Turkey, a country with territory in Europe, and could act as a vector for JEV in other regions. To assess the risk of these invasive species acting as vectors for JEV and therefore potentially contributing to its geographical expansion, we have investigated the vector competence of Ae. albopictus and Cx. quinquefasciatus.

METHODS: Two colonised lines of Ae. albopictus (Italy and Spain) and a line of Cx. quinquefasciatus (Tanzania) were compared for susceptibility to infection by oral feeding with JEV strain SA-14, genotype III at 106 PFU/ml and maintained at 25 °C. Specimens were processed at 7 and 14 days post-inoculation (dpi). Rates of infection, dissemination and transmission were assessed through detection of viral RNA by real-time polymerase chain reaction (RT-PCR) in mosquito body, legs and saliva, respectively, at each time point. Where possible, infection and dissemination were confirmed by immunohistochemical (IHC) detection of the JEV envelope protein.

RESULTS: Aedes albopictus from Italy showed no susceptibility to infection with JEV strain SA-14. Conversely, Ae. albopictus colonised in Spain was susceptible and 100% of infected mosquitoes that were subjected to saliva screening expressed viral RNA at 14 dpi. Culex quinquefasciatus was highly susceptible to infection as early as 7 dpi and 50% of infected mosquitoes that were subjected to saliva screening expressed viral RNA at 14 dpi. Infection and dissemination were confirmed in Cx. quinquefasciatus by IHC detection of JEV envelope protein in both the mid-gut and salivary glands.

CONCLUSIONS: Aedes albopictus from two different locations in Europe range from being susceptible to JEV and capable of transmission through to being resistant. Culex quinquefasciatus also appears highly susceptible; therefore, both species could potentially act as vectors for JEV and facilitate the emergence of JEV into new regions.

RevDate: 2022-06-16

Moore JH, Palmeirim AF, Peres CA, et al (2022)

Invasive rat drives complete collapse of native small mammal communities in insular forest fragments.

Current biology : CB pii:S0960-9822(22)00856-9 [Epub ahead of print].

As tropical forests are becoming increasingly fragmented, understanding the magnitude and time frame of biodiversity declines is vital for 21st century sustainability goals. Over three decades, we monitored post-isolation changes in small mammal species richness and abundance within a forest landscape fragmented by the construction of a dam in Thailand.1,2 We observed the near-complete collapse of species richness within 33 years, with no evidence of a recolonization effect across repeatedly sampled islands. Our results further revealed a decline in species richness as island size decreased and isolation time increased, accelerated by the increasing dominance of the ubiquitous Malayan field rat, Rattus tiomanicus. This species was already hyper-abundant on smaller islands in the initial surveys (1992-1994, 66% of individuals) but became monodominant on all islands, regardless of island size, by the most recent survey (2020, 97%). Our results suggest that insular forest fragments are highly susceptible to rapid species loss, particularly due to the competitive nature of Rattus accelerating the rate at which extinction debts are paid. To mitigate these impacts, reducing the extent of habitat degradation, as triggered by fragmentation and exacerbated by isolation time, can help to sustain native biodiversity while averting Rattus hyper-abundance.

RevDate: 2022-06-21

Lins DM, RM Rocha (2022)

Invasive species fouling Perna perna (Bivalvia: Mytilidae) mussel farms.

Marine pollution bulletin, 181:113829 pii:S0025-326X(22)00511-2 [Epub ahead of print].

Invasive, fouling species increase management costs and reduce mussel growth, which jeopardizes mariculture. We studied the distribution of eight invasive species in Santa Catarina, the leading mussel producer in Brazil. Our goals were to determine their spatial distribution and prevalence on farm structures (buoys, long lines, and mussel socks), as well as understand the relevance of propagule pressure (recruitment), port distance, and area of the farm in this distribution. Although present in all sites, adult and recruits distribution were spatially restricted, showing that species might have a metapopulation structure. The most prevalent species were the ascidian Styela plicata, the barnacle Megabalanus coccopoma, the bryozoan Schizoporella errata, and the polychaete Branchiomma luctuosum. Recruitment was the main driver of three species distribution while distance to port explained only one species distribution. Based on those results, we discuss policy options, management, and regulation enforcement, that can be used in the mussel aquaculture elsewhere.

RevDate: 2022-06-16

Twining JP, Lawton C, White A, et al (2022)

Restoring vertebrate predator populations can provide landscape-scale biological control of established invasive vertebrates: Insights from pine marten recovery in Europe.

Global change biology [Epub ahead of print].

Invasive species pose one of the greatest global threats to biodiversity. There has been a long history of importing coevolved natural enemies to act as biological control agents to try to suppress densities of invasive species, with historically limited success and frequent adverse impacts on native biodiversity. Our understanding of the processes and drivers of successful biological control has been focussed on invertebrates and is evidently limited and potentially ill-suited with respect to biological control of vertebrate populations. The restoration of native vertebrate predator populations provides a promising nature-based solution for slowing, halting, or even reversing the spread of some invasive vertebrates over spatial scales relevant to the management of wildlife populations. Here, we first review the growing literature and data from the pine marten-red and grey squirrel system in Europe. We synthesise a multi-decadal dataset to show that the recovery of a native predator has resulted in rapid, landscape-scale declines of an established invasive species. We then use the model system, predator-prey interaction theory, and examples from the literature to develop ecological theory relating to natural biological control in vertebrates and evolutionary processes in native-invasive predator-prey interactions. We find support for the hypotheses that evolutionary naivety of invasive species to native predators and lack of local refuges results in higher predation of naive compared to coevolved prey. We apply lessons learnt from the marten-squirrel model system to examine the plausibility of specific native predator solutions to some of the Earth's most devastating invasive vertebrates. Given the evidence, we conclude that depletion of vertebrate predator populations has increased ecosystem vulnerability to invasions and thus facilitated the spread of invasive species. Therefore, restoration of vertebrate predator populations is an underappreciated, fundamental, nature-based solution to the crisis of invasive species and should be a priority for vertebrate invasive species management globally.

RevDate: 2022-06-17
CmpDate: 2022-06-17

Yu Y, Cheng H, Wei M, et al (2022)

Silver nanoparticles intensify the allelopathic intensity of four invasive plant species in the Asteraceae.

Anais da Academia Brasileira de Ciencias, 94(2):e20201661 pii:S0001-37652022000301406.

This study aimed to estimate the allelopathic intensity of four Asteraceae invasive plant species (IPS), including Conyza canadensis (L.) Cronq., Erigeron annuus (L.) Pers., Bidens pilosa (L.), and Aster subulatus Michx., by testing the effect of leaf extracts on the seed germination and seedling growth (SGe and SGr) of lettuce (Lactuca sativa L.) in combination with two particle sizes of silver nanoparticles. These four IPS decreased the germination of lettuce seeds but increased the growth of lettuce seedlings. The allelopathic intensity of the four IPS decreased in the following order: B. pilosa > C. canadensis > E. annuus > A. subulatus. Silver nanoparticles decreased the SGe and SGr of lettuce. The 20 nm silver nanoparticles affected the competition intensity for water and the absorption of inorganic salts by lettuce more intensively than the 80 nm nanoparticles. Silver nanoparticles intensify the allelopathic intensity of the four invasive plant species on the SGe and SGr of lettuce. The allelopathic intensity of B. pilosa was higher than that of the other three IPS when they were polluted with silver nanoparticles. Thus, silver nanoparticles could facilitate the invasion process of the four IPS, particularly B. pilosa, via an increase in the intensity of allelopathy.

RevDate: 2022-06-16
CmpDate: 2022-06-16

Gao GF, Li H, Shi Y, et al (2022)

Continental-scale plant invasions reshuffle the soil microbiome of blue carbon ecosystems.

Global change biology, 28(14):4423-4438.

Theory and experiments support that plant invasions largely impact aboveground biodiversity and function. Yet, much less is known on the influence of plant invasions on the structure and function of the soil microbiome of coastal wetlands, one of the largest major reservoirs of biodiversity and carbon on Earth. We studied the continental-scale invasion of Spartina alterniflora across 2451 km of Chinese coastlines as our model-system and found that S. alterniflora invasion can largely influence the soil microbiome (across six depths from 0 to 100 cm), compared with the most common microhabitat found before invasion (mudflats, Mud). In detail, S. alterniflora invasion was not only positively associated with bacterial richness but also resulted in important biotic homogenization of bacterial communities, suggesting that plant invasion can lead to important continental scale trade-offs in the soil microbiome. We found that plant invasion changed the community composition of soil bacterial communities across the soil profile. Moreover, the bacterial communities associated with S. alterniflora invasions where less responsive to climatic changes than those in native Mud microhabitats, suggesting that these new microbial communities might become more dominant under climate change. Plant invasion also resulted in important reductions in the complexity and stability of microbial networks, decoupling the associations between microbes and carbon pools. Taken together, our results indicated that plant invasions can largely influence the microbiome of coastal wetlands at the scale of China, representing the first continental-scale example on how plant invasions can reshuffle the soil microbiome, with consequences for the myriad of functions that they support.

RevDate: 2022-06-20
CmpDate: 2022-06-20

Jiang S, He LM, He W, et al (2022)

Effects of X-ray irradiation on the fitness of the established invasive pest fall armyworm Spodoptera frugiperda.

Pest management science, 78(7):2806-2815.

BACKGROUND: Spodoptera frugiperda has spread to Africa, Asia, and Oceania, posing a serious threat to global agriculture. We estimated the appropriate dose of X-ray sterilization for S. frugiperda using an X-ray irradiation instrument to investigate environmentally acceptable control techniques, laying the framework for future applications of sterile insect technology (SIT) to manage the pest environmentally-friendly.

RESULTS: This study is the first to investigate the effects of X-ray irradiation on the growth, development, survival, reproduction, and flight of S. frugiperda. The results showed that irradiation with 50-400 Gy had no significant effect on pupal eclosion, but females were more sensitive than males in terms of reproductive parameters, especially when doses of radiation were > 350 Gy. After irradiation with a sub-sterilizing dose of 250 Gy, the parental sterility rate was > 85%, and the sterility traits could be passed on to their offspring, resulting in a continuous decrease in the population of F1 and F2 generations.

CONCLUSION: Our laboratory experiments theoretically confirmed the feasibility of SIT for controlling S. frugiperda in the field using X-ray radiation. This study provides a theoretical basis for future regional pest management strategies. © 2022 Society of Chemical Industry.

RevDate: 2022-06-15

Fine JD, EM Litsey (2022)

Drone Laying Honey Bee Workers in Queen Monitoring Cages.

Journal of insect science (Online), 22(3):.

Techniques to monitor honey bee (Apis mellifera) egg production in cages allow researchers to study how different environmental factors contribute to reproduction. However, although the conditions required to facilitate queen egg production in a laboratory setting have been established, limited work has addressed the requirements for stimulating and monitoring worker egg laying. Here, we documented that drone laying workers will lay eggs in Queen Monitoring Cages (QMC), specialized cages designed to facilitate queen egg laying under controlled conditions. Egg production and worker mortality were compared between QMCs containing queens and those containing drone laying workers. High-definition images of the last abdominal segments of living first-instar larvae hatched from worker laid eggs and those putatively laid by queens were qualitatively compared to identify candidate characteristics to determine their sex.

RevDate: 2022-06-15

Borden JB, San Antonio KM, Tomat-Kelly G, et al (2022)

Invasive grass indirectly alters seasonal patterns in seed predation.

Biology letters, 18(6):20220095.

Invasive species threaten ecosystems globally, but their impacts can be cryptic when they occur indirectly. Invader phenology can also differ from that of native species, potentially causing seasonality in invader impacts. Yet, it is unclear if invader phenology can drive seasonal patterns in indirect effects. We used a field experiment to test if an invasive grass (Imperata cylindrica) caused seasonal indirect effects by altering rodent foraging and seed predation patterns through time. Using seeds from native longleaf pine (Pinus palustris), we found seed predation was 25% greater, on average, in invaded than control plots, but this effect varied by season. Seed predation was 24-157% greater in invaded plots during spring and autumn months, but invasion had no effect on seed predation in other months. One of the largest effects occurred in October when longleaf pine seeds are dispersed, suggesting potential effects on tree regeneration. Thus, seasonal patterns in indirect effects from invaders may cause underappreciated impacts on ecological communities.

RevDate: 2022-06-15

Sher AA, Marshall DL, SA Gilbert (2000)

Competition between Native Populus deltoides and Invasive Tamarix ramosissima and the Implications for Reestablishing Flooding Disturbance.

Conservation biology : the journal of the Society for Conservation Biology, 14(6):1744-1754.

Changes in historical disturbance regimes have been shown to facilitate non-native plant invasions, but reinstatement of disturbance can be successful only if native colonizers are able to outcompete colonizing invasives. Reintroduction of flooding in the southwestern United States is being promoted as a means of reestablishing Populus deltoides subsp. wislizenii, but flooding can also promote establishment of an introduced, invasive species, Tamarix ramosissima. We investigated competition between Populus and Tamarix at the seedling stage to aid in characterizing the process by which Tamarix may invade and to determine the potential ability of Populus to establish itself with competitive pressure from Tamarix. We planted seedlings of Tamarix and Populus in five ratios at three densities for a total of 15 treatments. The growth response of each species was measured in terms of height, above-ground biomass, and tissue concentrations of nitrogen and phosphorous. These measurements across treatments were modeled as three-dimensional response surfaces. For both species, Populus density was more important than Tamarix density for determining growth response. Both species were negatively affected by increasing numbers of Populus seedlings. Due to the larger size of the native Populus, we predict that its superior competitive ability can lead to its dominance when conditions allow native establishment. Our results suggest that even in the presence of an invader that positively responds to disturbance, reestablishment of historical flooding regimes and post-flood hydrology can restore this ecosystem by promoting its dominant plant species.

RevDate: 2022-06-15
CmpDate: 2022-06-15

Deblauwe I, De Wolf K, De Witte J, et al (2022)

From a long-distance threat to the invasion front: a review of the invasive Aedes mosquito species in Belgium between 2007 and 2020.

Parasites & vectors, 15(1):206.

Invasive mosquito species (IMS) and their associated mosquito-borne diseases are emerging in Europe. In Belgium, the first detection of Aedes albopictus (Skuse 1894) occurred in 2000 and of Aedes japonicus japonicus (Theobald 1901) in 2002. Early detection and control of these IMS at points of entry (PoEs) are of paramount importance to slow down any possible establishment. This article reviews the introductions and establishments recorded of three IMS in Belgium based on published (2007-2014) and unpublished (2015-2020) data collected during several surveillance projects. In total, 52 PoEs were monitored at least once for the presence of IMS between 2007 and 2020. These included used tyre and lucky bamboo import companies, airports, ports, parking lots along highways, shelters for imported cutting plants, wholesale markets, industrial areas, recycling areas, cemeteries and an allotment garden at the country border with colonised areas. In general, monitoring was performed between April and November. Mosquitoes were captured with adult and oviposition traps as well as by larval sampling. Aedes albopictus was detected at ten PoEs, Ae. japonicus at three PoEs and Aedes koreicus (Edwards 1917) at two PoEs. The latter two species have established overwintering populations. The percentage of PoEs positive for Ae. albopictus increased significantly over years. Aedes albopictus is currently entering Belgium through lucky bamboo and used tyre trade and passive ground transport, while Ae. japonicus through used tyre trade and probably passive ground transport. In Belgium, the import through passive ground transport was first recorded in 2018 and its importance seems to be growing. Belgium is currently at the invasion front of Ae. albopictus and Ae. japonicus. The surveillance and control management actions at well-known PoEs associated to long-distance introductions are more straightforward than at less-defined PoEs associated with short-distance introductions from colonised areas. These latter PoEs represent a new challenge for IMS management in Belgium in the coming years. Aedes albopictus is expected to become established in Belgium in the coming years, hence increasing the likelihood of local arbovirus transmission. The implementation of a sustainable, structured and long-term IMS management programme, integrating active and passive entomological surveillance, vector control and Public Health surveillance is therefore pivotal.

RevDate: 2022-06-15
CmpDate: 2022-06-15

Bunting MD, Pfitzner C, Gierus L, et al (2022)

Generation of Gene Drive Mice for Invasive Pest Population Suppression.

Methods in molecular biology (Clifton, N.J.), 2495:203-230.

Gene drives are genetic elements that are transmitted to greater than 50% of offspring and have potential for population modification or suppression. While gene drives are known to occur naturally, the recent emergence of CRISPR-Cas9 genome-editing technology has enabled generation of synthetic gene drives in a range of organisms including mosquitos, flies, and yeast. For example, studies in Anopheles mosquitos have demonstrated >95% transmission of CRISPR-engineered gene drive constructs, providing a possible strategy for malaria control. Recently published studies have also indicated that it may be possible to develop gene drive technology in invasive rodents such as mice. Here, we discuss the prospects for gene drive development in mice, including synthetic "homing drive" and X-shredder strategies as well as modifications of the naturally occurring t haplotype. We also provide detailed protocols for generation of gene drive mice through incorporation of plasmid-based transgenes in a targeted and non-targeted manner. Importantly, these protocols can be used for generating transgenic mice for any project that requires insertion of kilobase-scale transgenes such as knock-in of fluorescent reporters, gene swaps, overexpression/ectopic expression studies, and conditional "floxed" alleles.

RevDate: 2022-06-14

Shiraki S, K Kakui (2022)

Observations on Predation in Paranthura japonica Richardson, 1909 (Isopoda: Cymothoida: Paranthuridae).

Zoological science, 39(3):270-274.

Although isopods in Anthuroidea are predators, there is little information on their predatory behavior. In this study, we investigated predation by the paranthurid Paranthura japonica, which was originally described from northern Japan but has recently been reported as an invasive alien species in western America and Europe. Six crustacean species (two isopods, two amphipods, and two tanaidaceans, one of which does not co-occur with P. japonica in the wild) and one pycnogonid species were used as prey candidates in our experiments. Paranthura japonica preyed on all candidate species except the pycnogonid, grasping them with its falciform pereopods, inserting its piercing-type mouthparts, and sucking out the internal contents of the prey. Cannibalism or scavenging was observed when several P. japonica individuals were put in a single aquarium. This study showed that P. japonica is an aggressive predator; it consumed various crustaceans, including one it never encounters in the wild. Our results suggest that P. japonica will have a high impact on alien ecosystems it invades as a predator on native crustaceans. Cytochrome c oxidase subunit (COI) nucleotide sequences for putative P. japonica from Oshoro, Japan and a topotypic individual from Muroran confirmed that the population we dealt with was P. japonica.

RevDate: 2022-06-13

Yelenik S, Rose E, Cordell S, et al (2022)

The role of microtopography and resident species in post-disturbance recovery of arid habitats in Hawai'i.

Ecological applications : a publication of the Ecological Society of America [Epub ahead of print].

Habitat suitability indices (HSI) have been employed in restoration to identify optimal sites for planting native species. Often, HSI are based on abiotic variables and do not include biotic interactions, even though similar abiotic conditions can favor both native and non-native species. Biotic interactions such as competition may be especially important in invader-dominated habitats because invasive species often have fast growth rates and can exploit resources quickly. In this study we test the utility of an HSI of microtopography derived from airborne LiDAR to predict post-disturbance recovery and native planting success in native shrub-dominated and non-native, invasive grass-dominated dryland habitats in Hawai'i. The HSI uses high resolution digital terrain models to classify sites' microtopography as high, medium, or low suitability, based on wind exposure and topographic position. We used a split-plot before-after-control-impact design to implement a disturbance experiment within native shrub (Dodonaea viscosa) and non-native, invasive grass (Cenchrus clandestinus) dominated ecosystems across three microtopography categories. In contrast to previous studies using the same HSI, we found that microtopography was a poor predictor of pre-disturbance conditions for soil nutrients, organic matter content, or foliar C:N, within both Dodonaea and Cenchrus vegetation types. In invader-dominated Cenchrus plots, microtopography helped predict cover, but not as expected (i.e., highest cover would be in high-suitability plots): D. viscosa had the greatest cover in low-suitability and C. clandestinus had the greatest cover in medium-suitability plots. Similarly, in native-dominated Dodonaea plots, microtopography was a poor predictor of D. viscosa, C. clandestinus, and total plant cover. Although we found some evidence that microtopography helped inform post-disturbance plant recovery of D. viscosa and total plant cover, vegetation type was a more important predictor. Important for considering the success of plantings, percent cover of D. viscosa decreased while percent cover of C. clandestinus increased within both vegetation types 20 months after disturbance. Our results are evidence that HSIs based on topographic features may prove most useful for choosing planting sites in harsh habitats or those already dominated by native species. In more productive habitats, competition from resident species may offset any benefits gained from "better" suitability sites.

RevDate: 2022-06-13

de Camargo MP, Cunico AM, LC Gomes (2022)

Biological Invasions in Neotropical Regions: Continental Ichthyofauna and Risk Assessment Protocols.

Environmental management [Epub ahead of print].

The objectives of this study were to compare four risk assessment protocols for non-native species in neotropical regions and to assess the potential application of these tools for the management of invasive species and conservation of the ichthyofauna in Brazil. The protocols Fish Invasiveness Screening Kit (FISK), Aquatic Species Invasiveness Screening Kit (AS-ISK), European Non-Native Species in Aquaculture Risk Assessment Scheme (ENSARS) and Fish Invasiveness Screening Test (FIST) were applied for the species Oreochromis niloticus, Coptodon rendalli, Poecilia reticulata and Apteronotus aff. albifrons, whose sources of introduction are aquaculture and fishkeeping. The species were classified as low, medium or high risk of invasion. The scores of the species O. niloticus, C. rendalli and P. reticulata classified them as high risk of invasion in all protocols, whereas A. aff. albifrons had medium risk in the protocols FISK and AS-ISK and low risk in the FIST. Although the results were similar for species whose impacts are widely described, less studied species may have their classification compromised by the lack of evidences in the literature. Despite the difficulties for practical application, the use of these tools may be encouraged, considering the potential threats of other invasive species emerging in Brazil. The comparison between the methods showed that the use of AS-ISK, combined with ENSARS in cases of introductions by aquaculture, provides important answers about ecological impacts on natural environments and about the stages of the aquaculture production chain that should be better inspected.

RevDate: 2022-06-13

Carpenter JK, Monks A, Innes J, et al (2022)

Pushing the limits: ship rat (Rattus rattus) population dynamics across an elevational gradient in response to mast seeding and supplementary feeding.

Biological invasions pii:2829 [Epub ahead of print].

Understanding marginal habitat use by invasive species is important for predicting how distributions may change under future climates. We investigated the influence of food availability and temperature on ship rat (Rattus rattus) distribution and density across a forested elevational gradient in New Zealand by measuring ship rat demographics following a beech (Nothofagaceae) mass seeding event ('mast') at three elevation bands (20-80, 400-500, 800-900 m asl). We tested whether declining food availability limits rat populations at the highest elevation band post-mast by experimentally increasing food abundance above baseline food availability. When our study started 4 months post-seedfall, rats at mid- and low- elevations were at high densities (11.4-16.5 ha-1). Rats at higher elevations were barely detectable, but densities peaked (9.4 ha-1) 10 months post-seedfall, with the initial increase possibly driven by immigration from lower elevations. All populations declined sharply over the next year. Supplementary feeding at high elevation increased survival, recruitment, and density of rats through winter, 16 months post-seedfall, relative to unfed grids, suggesting food limitation. However, both fed and non-fed populations declined to zero by the following spring, perhaps due to stoat (Mustela erminea) predation. Our results suggest that low food availability plays a significant role in restricting rats from cool, high elevation environments. The variation in the timing and magnitude of ship rat responses to the pulsed resource across the gradient also highlights the importance of initial population size and spatial processes as factors modulating ship rat responses to pulsed resources across a landscape.

Supplementary Information: The online version contains supplementary material available at 10.1007/s10530-022-02829-z.

RevDate: 2022-06-11

Chu M, X Zhang (2022)

Alien species invasion of deep-sea bacteria into mammal gut microbiota.

Journal of advanced research pii:S2090-1232(22)00123-0 [Epub ahead of print].

INTRODUCTION: Deep sea has numerous bacteria which dominate in the biomass of deep-sea sediments. Some deep-sea bacteria may possess the capacity to destroy mammal health by the alteration of gut microbiota, acting as potential pathogens.

OBJECTIVES: Pathogenic bacteria are great threats to human health. However, the ultimate origin of pathogenic bacteria has not been intensively explored. In this study, therefore, the influence of deep-sea bacteria on the gut microbiota was evaluated on a global scale.

METHODS: The bacteria isolated from each of 106 deep-sea sediment samples were transplanted into mice in our study to assess the infectiousness of deep-sea bacteria.

RESULTS: The results showed that some bacteria from deep sea, an area that has existed since the earth was formed, could proliferate in mouse gut. Based on the infectious evaluation of the bacteria from each of 106 deep-sea sediments, the bacteria isolated from 13 sediments invaded the gut bacterial communities of mice, leading to the significant alteration of mouse gut microbiota. Among the 13 deep-sea sediments, the bacteria isolated from 9 sediments could destroy mouse health by inducing glucose metabolism deterioration, liver damage and inflammatory symptom. As an example, a bacterium was isolated from deep-sea sediment DP040, which was identified to be Bacillus cereus (termed as Bacillus cereus DP040). Bacillus cereus DP040 could invade the gut microbiota of mice to change the gut microbial structure, leading to inflammatory symptom of mice. The deep-sea sediments containing the bacteria destroying the health of mice were distributed in hydrothermal vent, mid-ocean ridge and hadal trench of the Indian Ocean, the Atlantic Ocean and the Pacific Ocean.

CONCLUSIONS: Our findings demonstrate that deep sea is an important origin of potential pathogenic bacteria and provide the first biosecurity insight into the alien species invasion of deep-sea bacteria into mammal gut microbiota.

RevDate: 2022-06-11

Zilkey DR, KA Moser (2022)

Diatom community composition on submerged macrophyte species from an Ontario (Canada) lake.

Journal of phycology [Epub ahead of print].

The introduction of invasive macrophyte species can affect submerged macrophyte community composition and abundance, which in turn can alter the functions of lake ecosystems. Knowing when and how invasive macrophytes arrive and spread can help disentangle the effects of invasive species from other stressors on lake ecosystems. This requires a long-term (decades) perspective of macrophyte community composition, which is rarely available. An alternative is paleolimnological inferences of macrophyte community composition from fossil diatom assemblages, which requires knowledge of epiphytic diatom communities. Here, we investigated the epiphytic diatom community composition of three common submerged macrophyte species (Chara sp., Potamogeton robbinsii, and the invasive Myriophyllum spicatum) in a typical temperate, mixed forest lake, Chandos Lake, Ontario, Canada, to provide a basis for future paleolimnological research. Non-parametric, multivariate analysis of variance indicated a statistically significant difference in the epiphytic diatom communities of different macrophyte species, despite principal components analysis showing some overlap among the diatom communities. Diatom community composition of all macrophytes had abundant Achnanthidium minutissimum and Cocconeis placentula. Generalised linear models and univariate analysis of variance identified six diatoms (Encyonopsis microcephala, Epithemia turgida, Gomphonema pavulum var. parvulius, Navicula gerloffi, Rhopalodia gibba, and Rossithidium anastasiae) that were significantly different among macrophyte species. Although it remains uncertain whether these differences are sufficient to infer historical macrophyte community composition from epiphytic diatom fossil assemblages, our results indicate the potential of such an approach and offer suggestions for future research.

RevDate: 2022-06-10

Barton DP, Gherman CM, Zhu X, et al (2022)

Characterization of tongue worms, Linguatula spp. (Pentastomida) in Romania, with the first record of an unknown adult Linguatula from roe deer (Capreolus capreolus Linnaeus).

Parasitology research [Epub ahead of print].

Specimens of the pentastomid parasite, Linguatula serrata, have been reported from several animals in Romania, including some domestic dogs translocated to other parts of Europe. In this study, gray wolves (Canis lupus, n = 80), golden jackals (C. aureus, n = 115), red foxes (Vulpes vulpes, n = 236), and roe deer (Capreolus capreolus, n = 1) were examined for pentastomes. Overall, 17.5% of wolves were found to be infected with specimens of Linguatula, with a range of infections of one to five individuals per animal. Golden jackals and foxes had much lower infection levels, with 1.73% of golden jackals and 1.69% of foxes infected; both host species were found to be infected with one or two individual pentastomes per animal. The single deer specimen was infected with three individual pentastomes. The pentastomes collected from the wolves and golden jackals were determined to be immature and mature adult specimens of L. serrata based on morphological examination and molecular analysis using the 18S rRNA gene. No pentastomes collected from the red foxes were available for identification. The pentastomes collected from the roe deer were expected to be L. arctica but determined to be mature adult male specimens of an unknown Linguatula, herein, referred to as Linguatula sp. based on its morphology; the results of molecular sequencing for the Linguatula specimen collected from the deer were inconclusive, preventing a final species identification. This study presents the first report of L. serrata in any hosts from Romania through both morphological and molecular characterization, and also presents the first report of a Linguatula sp. in Ca. capreolus, utilizing morphological characterization. Issues of morphological variability are discussed, including the presence of spines in the hook pit of specimens of Linguatula. This study highlights the need to examine all specimens of Linguatula to confirm the stage of development. Despite the inconclusive molecular result for some specimens, the authors still urge future researchers to incorporate a combined molecular and morphological approach in identifying specimens of Linguatula.

RevDate: 2022-06-10

Jenckel M, Hall RN, T Strive (2022)

Pathogen profiling of Australian rabbits by metatranscriptomic sequencing.

Transboundary and emerging diseases [Epub ahead of print].

Australia is known for its long history of using biocontrol agents, like myxoma virus (MYXV) and rabbit haemorrhagic disease virus (RHDV), to manage wild European rabbit populations. Interestingly, while undertaking RHDV surveillance of rabbits that were found dead we observed that approximately 40% of samples were negative for RHDV. To investigate whether other infectious agents are responsible for killing rabbits in Australia we subjected a subset of these RHDV-negative liver samples to metatranscriptomic sequencing. In addition, we investigated whether the host transcriptome data could provide additional differentiation between likely infectious versus non-infectious causes of death. We identified transcripts from several Clostridia species, Pasteurella multocida, Pseudomonas spp., and Eimeria stiedae in liver samples of several rabbits that had died suddenly, all of which are known to infect rabbits and are capable of causing disease and mortality. In addition, we identified Hepatitis E virus and Cyniclomyces yeast in some samples, both of which are not usually associated with severe disease. In one third of the sequenced total liver RNAs, no infectious agent could be identified. While metatranscriptomic sequencing cannot provide definitive evidence of causation, additional host transcriptome analysis provided further insights to distinguish between pathogenic microbes and commensals or environmental contaminants. Interestingly, three samples where no pathogen could be identified showed evidence of upregulated host immune responses, while immune response pathways were not upregulated when E. stiedae, Pseudomonas, or yeast were detected. In summary, although no new putative rabbit pathogens were identified, this study provides a robust workflow for future investigations into rabbit mortality events. This article is protected by copyright. All rights reserved.

RevDate: 2022-06-10

Roth CL, O'Neil ST, Coates PS, et al (2022)

Targeting Sagebrush (Artemisia Spp.) Restoration Following Wildfire with Greater Sage-Grouse (Centrocercus Urophasianus) Nest Selection and Survival Models.

Environmental management [Epub ahead of print].

Unprecedented conservation efforts for sagebrush (Artemisia spp.) ecosystems across the western United States have been catalyzed by risks from escalated wildfire activity that reduces habitat for sagebrush-obligate species such as Greater Sage-Grouse (Centrocercus urophasianus). However, post-fire restoration is challenged by spatial variation in ecosystem processes influencing resilience to disturbance and resistance to non-native invasive species, and spatial and temporal lags between slower sagebrush recovery processes and faster demographic responses of sage-grouse to loss of important habitat. Decision-support frameworks that account for these factors can help users strategically apply restoration efforts by predicting short and long-term ecological benefits of actions. Here, we developed a framework that strategically targets burned areas for restoration actions (e.g., seeding or planting sagebrush) that have the greatest potential to positively benefit sage-grouse populations through time. Specifically, we estimated sagebrush recovery following wildfire and risk of non-native annual grass invasion under four scenarios: passive recovery, grazing exclusion, active restoration with seeding, and active restoration with seedling transplants. We then applied spatial predictions of integrated nest site selection and survival models before wildfire, immediately following wildfire, and at 30 and 50 years post-wildfire based on each restoration scenario and measured changes in habitat. Application of this framework coupled with strategic planting designs aimed at developing patches of nesting habitat may help increase operational resilience for fire-impacted sagebrush ecosystems.

RevDate: 2022-06-10

EFSA Panel on Plant Health (PLH), Bragard C, Baptista P, et al (2022)

Pest categorisation of Oligonychus perseae.

EFSA journal. European Food Safety Authority, 20(6):e07336 pii:EFS27336.

The EFSA Panel on Plant Health performed a pest categorisation of Oligonychus perseae (Acari: Prostigmata: Tetranychidae), the persea mite, for the EU. O. perseae is a tropical species that originated in Mesoamerica and has now spread and established in California, Florida, Hawaii, Morocco, southern Europe and Israel. Within the EU, it is established in Italy, Portugal and Spain. O. perseae is not listed in Commission Implementing Regulation (EU) 2019/2072. It is polyphagous, feeding on plants in 20 genera in 17 families. It is most frequently reported on avocado (Persea americana), where it is considered a key pest. No evidence was found indicating damage to other crops. O. perseae live on leaves and do not attack the fruit. Populations usually grow exponentially at the beginning of summer and decline at the end of this season. High population densities can cause severe defoliation, resulting in downgrading of fruit through sunburn. However, this type of damage is common only if trees additionally suffer from water stress. The lack of additional avocado pests in the EU, which facilitates the production of organic avocados, is jeopardised by the occurrence of this mite, as it may require pesticide applications. This is why O. perseae is considered an important pest of avocados in Spain, where more than 80% of EU avocado production occurs. Natural dispersal is restricted to neighbouring trees. However, human-assisted movement can result in long-distance spread. Plants for planting provide potential pathways for further entry and spread, including O. perseae-free EU MS where avocados are grown (i.e. Cyprus, France, Greece). Climatic conditions and availability of host plants in southern EU countries are conducive for establishment. Phytosanitary measures are available to reduce the likelihood of further entry and spread. O. perseae satisfies with no key uncertainties the criteria that are within the remit of EFSA to assess for it to be regarded as a potential Union quarantine pest.

RevDate: 2022-06-10

Gašparovičová P, Ševčík M, S David (2022)

The Prediction of Distribution of the Invasive Fallopia Taxa in Slovakia.

Plants (Basel, Switzerland), 11(11): pii:plants11111484.

Invasive species are now considered the second biggest threat for biodiversity and have adverse environmental, economic and social impacts. Understanding its spatial distribution and dynamics is crucial for the development of tools for large-scale mapping, monitoring and management. The aim of this study was to predict the distribution of invasive Fallopia taxa in Slovakia and to identify the most important predictors of spreading of these species. We designed models of species distribution for invasive species of Fallopia-Fallopia japonica-Japanese knotweed, Fallopia sachalinensis-Sakhalin knotweed and their hybrid Fallopia × bohemica-Czech knotweed. We designed 12 models-generalized linear model (GLM), generalized additive model (GAM), classification and regression trees (CART), boosted regression trees (BRT), multivariate adaptive regression spline (MARS), random forests (RF), support vector machine (SVM), artificial neural networks (ANN), maximum entropy (Maxent), penalized maximum likelihood GLM (GLMNET), domain, and radial basis function network (RBF). The accuracy of the models was evaluated using occurrence data for the presence and absence of species. The final simplified logistic regression model showed the three most important prediction variables lead by distances from roads and rails, then type of soil and distances from water bodies. The probability of invasive Fallopia species occurrence was evaluated using Pearson's chi-squared test (χ21). It significantly decreases with increasing distance from transport lines (χ21 = 118.85, p < 0.001) and depends on soil type (χ21 = 49.56, p < 0.001) and the distance from the water, where increasing the distance decrease the probability (χ21 = 8.95, p = 0.003).

RevDate: 2022-06-10

Pedro SI, Rosado T, Barroca C, et al (2022)

Characterisation of the Phenolic Profile of Acacia retinodes and Acacia mearnsii Flowers' Extracts.

Plants (Basel, Switzerland), 11(11): pii:plants11111442.

Acacia spp. is an invasive species that is widespread throughout the Portuguese territory. Thus, it is pertinent to better understand this species in order to find different applications that will value its use. To evaluate the phenolic profile in Acacia flowers, ethanolic extracts obtained through an energized guided dispersive extraction were analysed, focusing on two species, Acacia retinodes and Acacia mearnsii, at two flowering stages. The phytochemical profile of each extract was determined by ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry and high-performance liquid chromatography coupled with diode array detector. The FTIR-ATR technique was used to distinguish the different samples' compositions. The results showed the presence of high concentrations of phenolic compounds (>300 mg GAE/g extract), among which are flavonoids (>136 mg QE/g extract), for all combinations of species/flowering stages. The phytochemical profile showed a complex composition with 21 compounds identified and quantified (the predominant ones being epicatechin, rutin, vanillin, and catechol). Both species and flowering stages presented significant variations regarding the presence and quantity of phenols and flavonoids, so much so that a principal component analysis performed with FTIR-ATR spectra data of the extracts was able to discriminate between species and flowering stages.

RevDate: 2022-06-10

Kennedy BPA, Boyle N, Fleming PJS, et al (2022)

Ethical Treatment of Invasive and Native Fauna in Australia: Perspectives through the One Welfare Lens.

Animals : an open access journal from MDPI, 12(11): pii:ani12111405.

The One Welfare concept is proposed to guide humans in the ethical treatment of non-human animals, each other and the environment. One Welfare was conceptualized for veterinarians but could be a foundational concept through which to promote the ethical treatment of animals that are outside of direct human care and responsibility. However, wild-living animals raise additional ethical conundrums because of their multifarious values and roles, and relationships that humans have with them. At an open facilitated forum, the 2018 Robert Dixon Memorial Animal Welfare Symposium, a panel of five experts from different fields shared their perspectives on "loving and hating animals in the wild" and responded to unscripted questions from the audience. The Symposium's objectives were to elucidate views on the ethical treatment of the native and invasive animals of Australia and to identify some of the resultant dilemmas facing conservationists, educators, veterinarians and society. Here, we document the presented views and case studies and synthesize common themes in a One Welfare framework. Additionally, we identified points of contention that can guide further discourse. With this guide in place, the identification and discussion of those disparate views was a first step toward practical resolutions on how to manage wild-living Australian fauna ethically. We concluded that there was great utility in the One Welfare approach for any discourse about wild animal welfare. It requires attention to each element of the triple bottom line and ensures that advocacy for one party does not vanquish the voices from other sectors. We argue that, by facilitating a focus on the ecology in the context of wild animal issues, One Welfare is more useful in this context than the veterinary context for which it was originally developed.

RevDate: 2022-06-10

Cabezas MP, Lasso-Alcalá OM, Quintero-T E, et al (2022)

Clarifying the taxonomy of some cryptic blennies (Blenniidae) in their native and introduced range.

Scientific reports, 12(1):9514.

Omobranchus punctatus is native to the Indo-Pacific region and invasive in the Atlantic region, currently being considered one of the most widely distributed blenny species. However, recent molecular studies indicated that O. punctatus is a complex of species, with three divergent mtDNA lineages identified to date, stressing the need for a taxonomic revision. In this study, we used an integrative approach, combining morphological and genetic data, to shed light on the taxonomy and distribution of O. punctatus. Moreover, we provide the first genetic records of introduced populations in Brazil and discuss the introduction pattern of this species in this region. Morphological data shows that O. punctatus consists of at least five distinct and geographically restricted species: O. punctatus sensu stricto, O. dispar, O. sewalli, O. cf. kochi, and O. cf. japonicus. Species delimitation analyses performed using the mtDNA data available confirmed that O. punctatus sensu stricto, O. dispar and O. sewalli correspond to different species that started to diverge about 2.6 Mya. Furthermore, O. sewalli was identified as the invasive species colonizing Atlantic shores. The existence of historical oceanographic barriers, such as the emergence of the Sunda Shelf in the Eastern Indian Ocean during the Pleistocene, and the biological traits of these blennies are the most likely factors responsible for their genetic differentiation and subsequent speciation.

RevDate: 2022-06-10

Schneider DI, Sujii ER, Laumann RA, et al (2022)

Parasitoids of Drosophilids in the Brazilian Savanna: Spatial-temporal Distribution and Host Associations with Native and Exotic Species.

Neotropical entomology [Epub ahead of print].

Host-parasitoid interactions may have a relevant role not only in ecological processes but also in human procedures such as biological control and the management of invasive species. Although the Drosophila-parasitoid system has been widely used for investigating all aspects of host-parasitoid relationships, it is still poorly understood in tropical areas. Here, we investigate the richness, spatial-temporal distribution, and host associations of parasitoids attacking drosophilid flies in the core region of the Brazilian Savanna, a hotspot of biodiversity. Using different methods, we collected wasps on several occasions over 7 years and found 13 species representing families associated with drosophilid larvae (Figitidae, Braconidae) and pupae (Pteromalidae, Eurytomidae, Dipriidae). The dominant species infesting larvae and pupae were Dicerataspis grenadensis Ashmead and Pachycrepoideus vindemmiae (Rondani), respectively. Spalangia simplex Perkins was recorded for the first time in the Brazilian Savanna. Although our study was not designed to evaluate collection methods, we observed that they captured different subsets of the wasp community. The spatiotemporal distribution of wasps followed those of drosophilids: they were more abundant in forests and during the rainy season, suggesting that the abundance of hosts, especially native drosophilids, is an important factor determining the assemblage structure and population dynamics of parasitoids. Common parasitoids and drosophilids were associated with more than one host/antagonist species, suggesting that caution should be used for the selection of biological control agents. This study confirms the role and relevance of natural vegetation in preserving biodiversity and ecosystem services, especially in a biome severely threatened by agricultural expansion.

RevDate: 2022-06-10
CmpDate: 2022-06-10

Couton M, Lévêque L, Daguin-Thiébaut C, et al (2022)

Water eDNA metabarcoding is effective in detecting non-native species in marinas, but detection errors still hinder its use for passive monitoring.

Biofouling, 38(4):367-383.

Marinas are high-priority targets for marine non-indigenous species (NIS), where they compose a large portion of the biofouling communities. The practicality of water samples collection makes environmental DNA (eDNA) metabarcoding an interesting tool for routine NIS surveys. Here the effectiveness of water-eDNA-metabarcoding to identify biofouling NIS, in 10 marinas from western France, was examined. Morphological identification of specimens collected in quadrats brought out 18 sessile benthic NIS beneath floating pontoons. Water-eDNA-metabarcoding detected two thirds of them, failing to detect important NIS. However, sampling and bioinformatics filtering steps can be optimized to identify more species. In addition, this method allowed the detection of additional NIS from neighboring micro-habitats. Caution should, however, be taken when reporting putative novel NIS, because of errors in species assignment. This work highlights that water-eDNA-metabarcoding is effective for active (targeted) NIS surveys and could be significantly improved for its further use in marine NIS passive surveys.

RevDate: 2022-06-10
CmpDate: 2022-06-10

Bereza D, N Shenkar (2022)

Shipping voyage simulation reveals abiotic barriers to marine bioinvasions.

The Science of the total environment, 837:155741.

The shipping industry is considered the main vector of introduction of marine non-indigenous species (NIS). NIS distributions are often a consequence of frequent trade activities that are affected by economic trends. A dominant trend in the shipping industry is the operation of Ultra Large Container Vessels (ULCV), which are over 395 m long and sail mostly on the East-Asia - northern-Europe route. Understanding the risk of NIS introduction by this emerging shipping category is needed for devising strategies for sustainable shipping. Here, we conducted a controlled simulation of key abiotic factors that determine marine bioinvasion success: temperature, salinity, and food availability along selected routes, under two treatments: ULCV and intermediate-size vessels. We tested the effect of each treatment and the varying environmental conditions on the survival of two invasive ascidians (Chordata, Ascidiacea). We used survival analysis methods to locate predictors of ascidian mortality; Environmental conditions at ports with high mortality were used to identify similar major ports on a global scale as potential abiotic barriers. The key factors in ascidian mortality varied between the two species, but for both species, the treatment and salinity were dominant predictors for survival. We identified Port Klang, Rotterdam, and Dammam as ports with high mortality and located several globally distributed major ports that present similar environmental conditions. Our results highlight the potential role of selected major ports as abiotic barriers to fouling organisms during ocean voyages. The tolerance of the tropical-origin Microcosmus exasperatus to the northern-Europe conditions, and of the temperate/sub-tropical origin Styela plicata, to high temperature conditions, point out the urgent need to modify international fouling regulations in view of global change. Further studies on the survival of fouling organisms during a cascade of changing environmental conditions will contribute to the advancement of science-based regulations to reduce the adverse effects of NIS.

RevDate: 2022-06-09

Withers AJ, Rice A, de Boer J, et al (2022)

The distribution of covert microbial natural enemies of a globally invasive crop pest, fall armyworm, in Africa: enemy-release and spillover events.

The Journal of animal ecology [Epub ahead of print].

Invasive species pose a significant threat to biodiversity and agriculture worldwide. Natural enemies play an important part in controlling pest populations, yet we understand very little about the presence and prevalence of natural enemies during the early invasion stages. Microbial natural enemies of fall armyworm (Spodoptera frugiperda) are known in its native region, however, they have not yet been identified in Africa where fall armyworm has been an invasive crop pest since 2016. Larval samples were screened from Malawi, Rwanda, Kenya, Zambia, Sudan, and Ghana for the presence of four different microbial natural enemies; two nucleopolyhedroviruses, Spodoptera frugiperda NPV (SfMNPV) and Spodoptera exempta NPV (SpexNPV); the fungal pathogen Metarhizium rileyi; and the bacterium Wolbachia. This study aimed to identify which microbial pathogens are present in invasive fall armyworm, and determine the geographical, meteorological, and temporal variables that influence prevalence. Within three years of arrival, fall armyworm was exposed to all four microbial natural enemies. SfMNPV probably arrived with fall armyworm from the Americas, but this is the first putative evidence of host spillover from Spodoptera exempta (African armyworm) to fall armyworm for the endemic pathogen SpexNPV and for Wolbachia. It is also the first confirmed incidence of M. rileyi infecting fall armyworm in Africa. Natural enemies were localised, with variation being observed both nationally and temporally. The prevalence of SfMNPV (the most common natural enemy) was predominantly explained by variables associated with the weather; declining with increasing rainfall and increasing with temperature. However, virus prevalence also increased as the growing season progressed. The infection of an invasive species with a natural enemy from its native range and novel pathogens specific to its new range has important consequences for understanding the population ecology of invasive species and insect-pathogen interactions. Additionally, whilst it is widely known that temporal and geographic factors affect insect populations, this study reveals that these are important in understanding the distribution of microbial natural enemies associated with invasive pests during the early stages of invasion, and provide baseline data for future studies.

RevDate: 2022-06-09

Woodyard ET, Bierman AE, Edwards JJ, et al (2022)

Kudoa hypoepicardialis and associated cardiac lesions in invasive red lionfish Pterois volitans in Grenada, West Indies.

Diseases of aquatic organisms, 149:97-108.

Invasive red lionfish Pterois volitans (Linnaeus, 1758) represent an ongoing ecological threat within temperate and tropical waters. Relatively little is known regarding the overall health of P. volitans and their potential for spreading pathogens in non-native regions. Lionfish collected from inshore reefs of Grenada, West Indies, in 2019 and 2021 were identified as P. volitans based on cytochrome c oxidase subunit 1 barcoding. Gross and microscopic examination of tissues revealed myxozoan plasmodia in the hearts of 24/76 (31.6%) lionfish by histopathology or wet mount cytology. Further histopathologic examination revealed severe granulomatous inflammation and myofiber necrosis associated with developing plasmodia and presporogonic life stages. Fresh myxospores were morphologically and molecularly consistent with Kudoa hypoepicardialis, being quadrate in apical view with 4 valves and 4 equal polar capsules. The spore body was 5.1-7.9 (mean: 6.0) µm long, 8.1-9.8 (8.7) µm wide, and 6.9-8.5 (7.7) µm thick. Polar capsules were 2.3-2.7 (2.5) µm long and 0.9-1.6 (1.3) µm wide. 18S small subunit rDNA sequences were 99.81-99.87% similar to sequence data from the original description of the species. Novel 28S large subunit rDNA and elongation factor 2 data, which did not match any previously reported species, were provided. This is the first account of a myxozoan parasite of P. volitans, a new host record and locality for K. hypoepicardialis, and one of few reports describing pathogen-associated lesions in invasive lionfish.

RevDate: 2022-06-09

Rodgers VL, Scanga SE, Kolozsvary MB, et al (2022)

Where Is Garlic Mustard? Understanding the Ecological Context for Invasions of Alliaria petiolata.

Bioscience, 72(6):521-537 pii:biac012.

The invasive plant Alliaria petiolata (garlic mustard) has spread throughout forest understory and edge communities in much of North America, but its persistence, density, and impacts have varied across sites and time. Surveying the literature since 2008, we evaluated both previously proposed and new mechanisms for garlic mustard's invasion success and note how they interact and vary across ecological contexts. We analyzed how and where garlic mustard has been studied and found a lack of multisite and longitudinal studies, as well as regions that may be under- or overstudied, leading to poor representation for understanding and predicting future invasion dynamics. Inconsistencies in how sampling units are scaled and defined can also hamper our understanding of invasive species. We present new conceptual models for garlic mustard invasion from a macrosystems perspective, emphasizing the importance of synergies and feedbacks among mechanisms across spatial and temporal scales to produce variable ecological contexts.

RevDate: 2022-06-09

Xia C, Chon TS, Takasu F, et al (2022)

Simulating Pine Wilt Disease Dispersal With an Individual-Based Model Incorporating Individual Movement Patterns of Vector Beetles.

Frontiers in plant science, 13:886867.

Individual movements of the insect vector pine sawyer beetles were incorporated into an individual-based model (IBM) to elucidate the dispersal of pine wilt disease (PWD) and demonstrate the effects of control practices. The model results were compared with the spatial data of infested pine trees in the Gijang-gun area of Busan, Republic of Korea. Step functions with long- and middle-distance movements of individual beetles effectively established symptomatic and asymptomatic trees for the dispersal of PWD. Pair correlations and pairwise distances were suitable for evaluating PWD dispersal between model results and field data at short and long scales, respectively. The accordance between model and field data was observed in infestation rates at 0.08 and 0.09 and asymptomatic rates at 0.16-0.17 for disease dispersal. Eradication radii longer than 20 m would effectively control PWD dispersal for symptomatic transmission and 20-40 m for asymptomatic transmission. However, the longer eradication radii were more effective at controlling PWD. Therefore, to maximize control effects, a longer radius of at least 40 m is recommended for clear-cutting eradication. The IBM of individual movement patterns provided practical information on interlinking the levels of individuals and populations and could contribute to the monitoring and management of forest pests where individual movement is important for population dispersal.

RevDate: 2022-06-08

Jones C, Skrip MM, Seliger BJ, et al (2022)

Spotted lanternfly predicted to establish in California by 2033 without preventative management.

Communications biology, 5(1):558.

Models that are both spatially and temporally dynamic are needed to forecast where and when non-native pests and pathogens are likely to spread, to provide advance information for natural resource managers. The potential US range of the invasive spotted lanternfly (SLF, Lycorma delicatula) has been modeled, but until now, when it could reach the West Coast's multi-billion-dollar fruit industry has been unknown. We used process-based modeling to forecast the spread of SLF assuming no treatments to control populations occur. We found that SLF has a low probability of first reaching the grape-producing counties of California by 2027 and a high probability by 2033. Our study demonstrates the importance of spatio-temporal modeling for predicting the spread of invasive species to serve as an early alert for growers and other decision makers to prepare for impending risks of SLF invasion. It also provides a baseline for comparing future control options.

RevDate: 2022-06-08
CmpDate: 2022-06-08

Netshituni VT, Cuthbert RN, Dondofema F, et al (2022)

Effects of wildfire ash from native and alien plants on phytoplankton biomass.

The Science of the total environment, 834:155265.

Wildfires are natural or anthropogenic phenomena increasing at alarming rates globally due to land-use alterations, droughts, climatic warming, hunting and biological invasions. Whereas wildfire effects on terrestrial ecosystems are marked and relatively well-studied, ash depositions into aquatic ecosystems have often remained overlooked, but have the potential to significantly impact bottom-up processes. This study assessed ash-water-phytoplankton biomass dynamics using six plant species [i.e., three natives (apple leaf Philenoptera violacea, Transvaal milk plum Englerophytum magalismontanum, quinine tree Rauvolfia caffra) and three aliens (lantana Lantana camara, gum Eucalyptus camaldulensis, guava Psidium guajava)] based on a six-week mesocosm experiment with different ash concentrations (1 and 2 g L-1). We assessed concentrations of chemical elements, i.e., N, P, K, Ca, Mg, Na, Mn, Fe, Cu, Zn and B from ash collected, and examined potential differences among the species. High concentrations of P, K, Mn, Fe, Cu, Zn and B were recorded from Transvaal milk plum ash and low concentrations of P, K, Ca, Mg, Cu and Zn were recorded from apple leaf. An increase in phytoplankton biomass (using chlorophyll-a concentration as a proxy) for all treatments i.e., 1 and 2 g L-1 and plant species was observed one week after, followed by decreases in the following weeks, with the exception of 2 g L-1 for lantana, gum and control groups. Silicate concentrations (i.e., used as a proxy for diatom abundance) showed increasing patterns among all ash treatments, with the exception of controls. However, no clear patterns were observed between native and alien plant ash for both chl-a and silicate concentrations. We found that ash has notable effects on water chemistry, particularly nitrate, which increased throughout the weeks, whereas, pH and conductivity were high at low ash concentrations. The impacts of ash on water chemistry, chl-a and silicate concentrations vary with individual species and the amount of ash deposited into the system.

RevDate: 2022-06-03
CmpDate: 2022-05-26

Nyamukondiwa C, Machekano H, Chidawanyika F, et al (2022)

Geographic dispersion of invasive crop pests: the role of basal, plastic climate stress tolerance and other complementary traits in the tropics.

Current opinion in insect science, 50:100878.

Global pest invasions have significantly increased in recent years. These invasions together with climate warming directly impact agriculture. Tropical climates feature extreme weather events, including high temperatures and seasonal droughts. Thus, successful invasive pests in tropics have to adapt to these extreme climate features. The intrinsic factors relevant to tropical invasion of insects have been explored in many studies, but the knowledge is rather dispersed in contemporary literature. Here, we reviewed the potential biophysical characters of successful invasive pests' adaption to tropical environments including [1] inherent high basal stress tolerance and advanced life-history performances [2], phenotypic plasticity [3], rapid evolution to environmental stress, polyphagy, diverse reproductive strategies and high fecundity. We summarised how these traits and their interactive effects enhance pest invasions in the tropics. Comprehensive understanding of how these characters facilitate invasion improves models for predicting ecological consequences of climate change on invasive pest species for improved pest management.

RevDate: 2022-06-07

Campbell C, Russo L, Albert R, et al (2022)

Whole community invasions and the integration of novel ecosystems.

PLoS computational biology, 18(6):e1010151 pii:PCOMPBIOL-D-21-01927.

The impact of invasion by a single non-native species on the function and structure of ecological communities can be significant, and the effects can become more drastic-and harder to predict-when multiple species invade as a group. Here we modify a dynamic Boolean model of plant-pollinator community assembly to consider the invasion of native communities by multiple invasive species that are selected either randomly or such that the invaders constitute a stable community. We show that, compared to random invasion, whole community invasion leads to final stable communities (where the initial process of species turnover has given way to a static or near-static set of species in the community) including both native and non-native species that are larger, more likely to retain native species, and which experience smaller changes to the topological measures of nestedness and connectance. We consider the relationship between the prevalence of mutualistic interactions among native and invasive species in the final stable communities and demonstrate that mutualistic interactions may act as a buffer against significant disruptions to the native community.

RevDate: 2022-06-07

Ji SX, Wang XD, Lin ZK, et al (2022)

Characterization of Chromatin Remodeling Genes Involved in Thermal Tolerance of Biologically Invasive Bemisia tabaci.

Frontiers in physiology, 13:865172 pii:865172.

As an invasive species, Bemisia tabaci Mediterranean (MED) has notable potential to adapt to a wide range of environmental temperatures, which enables it to successfully spread after invasion and occupy habitats over a wide latitude range. It has been postulated that chromatin remodeling mechanisms are related to the rapid acquisition of adaptive traits and thermal resistance in invasive species; however, relevant experimental evidence is scarce. To identify the molecular characteristics and assess the role of chromatin remodelers in thermal stress within invasive MED and native Asia II 1 of the B. tabaci species complex, we identified 13 switching defective/sucrose non-fermenting (SWI/SNF) and 10 imitation switch (ISWI) family members in the B. tabaci genome, analyzed their molecular characteristics and structures, and identified key mutation sites between MED and Asia II 1, then cloned the catalytic subunits, and revealed the difference in thermal tolerance function. The results showed that the expression levels of Bt-BRM-1 and Bt-BRM-2 were significantly higher in MED than in Asia II 1 during heat stress, and Bt-BRM-2 expression was significantly higher during cold stress. In addition, RNA interference results indicated that the two target genes had similar temperature tolerance function in the both two cryptic species. This study is the first to identify and analyze the molecular characteristics of SWI/SNF and ISWI family members and reveal their potential key roles in temperature tolerance in poikilothermic ectotherms. The results will assist in understanding the underlying temperature adaptation mechanism of invasive insects and will enrich stress adaptation research systems from an epigenetic perspective.

RevDate: 2022-06-07

Hay A, Riggins CL, Heard T, et al (2022)

Movement and mortality of invasive suckermouth armored catfish during a spearfishing control experiment.

Biological invasions pii:2834 [Epub ahead of print].

Control of non-native, invasive species in groundwater-dependent ecosystems that are also inhabited by regionally endemic or at-risk species represents a key challenge in aquatic invasive species management. Non-native suckermouth armored catfish (SAC; family Loricariidae) have invaded freshwater ecosystems on a global scale, including the groundwater-dependent upper San Marcos River in Texas, USA. We used passive integrated transponder tags to follow the movements and fates of 65 fish in a 1.6 km spring-fed reach of the upper San Macros River to assess the efficacy of a community-based spearfishing bounty hunt for controlling SAC. We found the weekly probability of SAC survival was negatively correlated with the number of fish removed as a part of the bounty hunt each week (P = 0.003, R 2 = 0.86), while the probability of SAC being speared and reported was positively correlated with the number of fish removed (P = 0.011, R 2 = 0.53). The majority of SAC used < 25 m2 of river over a nine-week tracking period, but the area of river fish used correlated positively with the number of relocations (P < 0.001, R 2 = 0.36) as might be expected for a population that disperses through diffusive spread. These findings collectively suggest local-scale suppression of the SAC population is possible through community engagement in spearfishing, but over longer time periods immigration might offset some of the removal success. This conclusion provides an explanation for the pattern in which long-term spearfishing tournaments have reduced biomass but ultimately not resulted in eradication of the population.

Supplementary Information: The online version contains supplementary material available at 10.1007/s10530-022-02834-2.

RevDate: 2022-06-07

Tian H, Koski TM, Zhao L, et al (2022)

Invasion History of the Pinewood Nematode Bursaphelenchus xylophilus Influences the Abundance of Serratia sp. in Pupal Chambers and Tracheae of Insect-Vector Monochamus alternatus.

Frontiers in plant science, 13:856841.

Pine wilt disease (PWD) has caused extensive mortality in pine forests worldwide. This disease is a result of a multi-species interaction among an invasive pinewood nematode (PWN) Bursaphelenchus xylophilus, its vector Monochamus sp. beetle, and the host pine tree (Pinus sp.). In other systems, microbes have been shown to attenuate negative impacts on invasive species after the invasion has reached a certain time point. Despite that the role of PWD associated microbes involved in the PWD system has been widely studied, it is not known whether similar antagonistic "hidden microbial players" exist in this system due to the lack of knowledge about the potential temporal changes in the composition of associated microbiota. In this study, we investigated the bacteria-to-fungi ratio and isolated culturable bacterial isolates from pupal chambers and vector beetle tracheae across five sampling sites in China differing in the duration of PWN invasion. We also tested the pathogenicity of two candidate bacteria strains against the PWN-vector beetle complex. A total of 118 bacterial species belonging to 4 phyla, 30 families, and 54 genera were classified based on 16S sequencing. The relative abundance of the genus Serratia was lower in pupal chambers and tracheae in newly PWN invaded sites (<10 years) compared to the sites that had been invaded for more than 20 years. Serratia marcescens strain AHPC29 was widely distributed across all sites and showed nematicidal activity against PWN. The insecticidal activity of this strain was dependent on the life stage of the vector beetle Monochamus alternatus: no insecticidal activity was observed against final-instar larvae, whereas S. marcescens was highly virulent against pupae. Our findings improved the understanding of the temporal variation in the microbial community associated with the PWN-vector beetle complex and the progress of PWD and can therefore facilitate the development of biological control agents against PWN and its vector beetle.

RevDate: 2022-06-06

Najberek K, Solarz W, Gąsienica-Staszeczek M, et al (2022)

Role of enemy release and hybridization in the invasiveness of Impatiens balfourii and I. glandulifera.

Journal of plant research [Epub ahead of print].

Comparative studies with taxonomically and geographically paired alien species that exhibit different degrees of success in their invasions may help to identify the factors that determine invasiveness. Examples of such species in Europe include the noninvasive Impatiens balfourii and invasive I. glandulifera. We tested whether the low invasiveness of I. balfourii in Europe may be explained by strong pressure from local enemies. Earlier studies of these two species provided support for their hybridization. We tested this phenomenon as the potential occurrence of I. glandulifera × I. balfourii hybrids might promote the evolution of the invasiveness of I. balfourii. Both species were germinated from seeds collected in 2015 on the Swiss-Italian border in Insubria and utilized in three experiments: (1) a common garden enemy release test (leaf damage or pest pressure), (2) a test of the pressure exerted by a generalist enemy and (3) hybridization test. In the first test, the effect of enemies was assessed by the level of leaf damage and the number of pests. In the second test, a food choice experiment with a generalist herbivore (Cepaea snails) was performed. In the hybridization test, the plants were placed in a climatic chamber for self-pollination and hand cross-pollination. Analyses of enemy release and Cepaea snail preference revealed that I. balfourii experienced higher enemy pressure than I. glandulifera; however, this was not reflected in the performance of the plants. Although I. glandulifera was larger, I. balfourii had greater fecundity. Thus, the invasion success of I. glandulifera could not be unambiguously attributed to its greater degree of release from enemies compared with the noninvasive I. balfourii. Additionally, we did not obtain any evidence of hybridization between the two species. Thus, we obtained no support for the hypothesis that the evolution of the invasiveness of I. balfourii could be enhanced through hybridization with I. glandulifera.

RevDate: 2022-06-06

Kim D, Taylor AT, TJ Near (2022)

Phylogenomics and species delimitation of the economically important Black Basses (Micropterus).

Scientific reports, 12(1):9113.

Informed management and conservation efforts are vital to sustainable recreational fishing and biodiversity conservation. Because the taxonomic rank of species is important in conservation and management strategies, success of these efforts depends on accurate species delimitation. The Black Basses (Micropterus) are an iconic lineage of freshwater fishes that include some of the world's most popular species for recreational fishing and world's most invasive species. Despite their popularity, previous studies to delimit species and lineages in Micropterus suffer from insufficient geographic coverage and uninformative molecular markers. Our phylogenomic analyses of ddRAD data result in the delimitation of 19 species of Micropterus, which includes 14 described species, the undescribed but well-known Altamaha, Bartram's, and Choctaw basses, and two additional undescribed species currently classified as Smallmouth Bass (M. dolomieu). We provide a revised delimitation of species in the Largemouth Bass complex that necessitates a change in scientific nomenclature: Micropterus salmoides is retained for the Florida Bass and Micropterus nigricans is elevated from synonymy for the Largemouth Bass. The new understanding of diversity, distribution, and systematics of Black Basses will serve as important basis for the management and conservation of this charismatic and economically important clade of fishes.

RevDate: 2022-06-06

Hede N, L Khandeparker (2022)

Ecological Impacts of Aged Freshwater Biofilms on Estuarine Microbial Communities Elucidated Through Microcosm Experiments: A Microbial Invasion Perspective.

Current microbiology, 79(7):210.

Inadvertent introductions of alien species via biofilms as a vector released through ballast water are of environmental importance, yet their consequences are not much known. In the present study, biofilm communities developed in an inland freshwater port under in situ and dark conditions were subjected to long-term dark incubations. Subsequently, the impact of these aged biofilms as vectors on estuarine water column communities were evaluated using microcosm experiments in the laboratory. Variations in biofilm and planktonic microbial communities were quantified using quantitative PCR.Upon prolonged dark incubation, a shift in bacterial diversity with an increase in tolerant bacterial communities better adapted to stress was observed. Actinobacteria were the dominant taxa in both aged biofilms upon dark incubations. The laboratory studies indicated that on exposure of these biofilms to estuarine water, resuscitation of Vibrio alginolyticus, V. parahaemolyticus, and V. cholerae from a dormant state existing in these biofilms to culturable form was observed. Moreover, the results revealed that both the biofilm types can pose a threat to the environment, but the degree of risk can be attributed to the imbalance caused by significant changes in the surrounding estuarine microbial communities. Consequently, this may result in either proliferation or decline of some genera with different metabolic potential and resuscitation of pathogenic forms not present earlier, thereby influencing the ecology of the environment. Quantifying these effects in the field using biofilm metagenomes with an emphasis on virulent species and understanding traits that enable them to adapt to changing environments is a way forward.

RevDate: 2022-06-06

Zečević K, Sudimac M, Majstorović H, et al (2022)

First Report of Yeast-Spot Disease of Soybean Seeds Caused by Eremothecium coryli in Serbia.

Plant disease [Epub ahead of print].

Over the last 15 years, the area planted with soybeans (Glycine max) in Serbia has increased drastically, from 131,000 hectares in 2005 to 230,000 in 2019, and the average yield reached 3.2 t/ha in 2020. The Province of Vojvodina is the most important soybean production region with 95% of the total soybean area in Serbia (www.stat.gov.rs). During the 2021 growing season, soybean seeds with various kinds of symptoms including colour changes, light and dark brown spots, blotching, necrosis, and shriveling were collected from soybean field before harvest of soybean cv. Dukat in the Tamiš locality (South Banat District, Vojvodina Province: GPS: 44°56'12.936"N 20°43'24.216"E) in Serbia. The incidence of symptomatic seeds was estimated at 6.4%. Symptomatic soybean seeds were surface disinfected with 2% NaOCl for 2 min, rinsed in sterile water, dried on sterile filter paper, placed on potato dextrose agar (PDA) and were incubated at 25°C in the dark for 10 to 14 days. The identification of fungi at the genus level based on morphological characteristics revealed the presence of species of Macrophomina, Botrytis, Cercospora and Alternaria, which were previously reported as pathogens of soybean seed in Serbia (Krsmanović et al. 2020). Also, seven white to slightly creamy colonies with yeast-like morphology were observed around seeds expressing discoloration and necrotic and sunken spots. Ten days later, microscopic observations of yeast-like colonies revealed the presence of globose budding cells (diameter of 20 to 28 μm) mostly single or rarely in short chains. Also, two to eight needle-shaped ascospores (52 to 80 μm in length) were arranged lengthwise in many cylindrical to naviculate asci (60 to 96 x 8 to 12, avg. 72.4 x 9.2 µm). Ascospores were with a unilateral, slender, flexuous, whip-like appendage. The morphology of the different fungal structures indicated that the pathogen was Eremothecium coryli (Pelgion) Kurtzman and it was further supported by molecular identification. Total DNA was extracted directly from fungal mycelium with a DNeasy Plant Mini Kit (Qiagen, Hilden, Germany) and PCR amplification performed with primers ITS1F (Gardes and Bruns 1993) and ITS4 (White et al. 1990). Sequence analysis of ITS region revealed that the Serbian isolate ND2/21 (GenBank Accession No. OL958602) shared the highest nucleotide identity of 100% with E. coryli isolate (Accession No. KY103387). For pathogenicity test, fresh soybean seeds (cv. Sava) were surface-disinfected with 2% NaOCl and rinsed in sterile water before inoculation. The seeds were pierced 3-4 times with a sterile insect pin through a drop of yeast suspension (concentration 106 ascospores/ml) of one selected single-spore isolate (ND2-21). Similarly, control seeds were pierced with sterile insect pins through a drop of sterile distilled water. Five inoculated seeds and control (five replicates per treatment) were arranged uniformly in a Petri dish (9 cm diameter) and incubated at 22 to 25°C in the dark and kept under >95% relative humidity during the first 48 h. Twenty days after inoculation, small brown necrotic lesions were visible on the soybean seeds. Re-isolation from symptomatic seeds on PDA dishes yielded yeast-like colonies with the same morphological characteristics as those used for inoculation, thus confirming Koch's postulates. The control seeds had no symptoms. This fungus is widely known as a pathogen of yeast spot disease on soybean seeds (Heinrichs et al. 1976; Kimura et al. 2008), but to our knowledge, it has never been reported in Serbia. Considering that invasive species Nezara viridula L. and Halyomorpha halys (STÅL, 1855), the vectors of this fungus, were reported in our country (Kereši et al. 2012; Šeat 2015) and that their mass appearance has been documented in recent years (Konjević et al. 2020), the presence of this pathogen has the potential to cause considerable damage and severe yield losses, resulting in significant economic impact on soybean production in Serbia.

RevDate: 2022-06-06

Gallitelli L, Battisti C, Pietrelli L, et al (2022)

Anthropogenic particles in coypu (Myocastor coypus; Mammalia, Rodentia)' faeces: first evidence and considerations about their use as track for detecting microplastic pollution.

Environmental science and pollution research international [Epub ahead of print].

Anthropogenic plastic litter is widespread in all environments, with particular emphasis on aquatic habitats. Specifically, although freshwater mammals are important as they are at the top of food web, research mainly focus on marine animals, while only few studies have been carried out on freshwater mammals. The main gap is that microplastics (MP) are completely understudied in freshwater mammals. Here, we reported the first evidence of the presence of anthropogenic particles (including MP) in coypu (Myocastor coypus)' faeces. Coypu is a rodent mammal inhabiting rivers and wetland areas, and we discussed our preliminary data suggesting the use of these tracks as possible future bioindicator of MP pollution in wetlands and freshwaters. We collected 30 coypu's faeces in "Torre Flavia wetland" nature reserve. Then, in laboratory, faeces were digested in 30 ml hydrogen peroxide (30%) for a week a 20 °C and analysed under stereoscope. All the suspected found MP were isolated in a petri dish, using FT-IR analysis to confirm the polymers. Overall, we recorded 444 natural and anthropogenic particles with most of items being fibres. FT-IR analysis of the 10% of the particles recovered revealed that 72% of them was not MP (mainly, polyethylene, polyethylene terephthalate, and polyamide). Also, the number of anthropogenic particles is not correlated with the faecal weight. Given that alien species, such as coypu, are widespread species, our results might have a great importance as these species and MP in faecal tracks may be used as undirect proxy of environmental bioavailability of MP pollution.

RevDate: 2022-06-06

Bezabih B, Li J, Yuan J, et al (2022)

Non-native plant invasion can accelerate global climate change by increasing wetland methane and terrestrial nitrous oxide emissions.

Global change biology [Epub ahead of print].

Approximately 17% of the land worldwide is considered highly vulnerable to non-native plant invasion, which can dramatically alter nutrient cycles and influence greenhouse gas (GHG) emissions in terrestrial and wetland ecosystems. However, a systematic investigation of the impact of non-native plant invasion on GHG dynamics at a global scale has not yet been conducted, making it impossible to predict the exact biological feedback of non-native plant invasion to global climate change. Here, we compiled 273 paired observational cases from 94 peer-reviewed articles to evaluate the effects of plant invasion on GHG emissions and to identify the associated key drivers. Non-native plant invasion significantly increased methane (CH4) emissions from 129 kg CH4 ha-1 yr-1 in natural wetlands to 217 kg CH4 ha-1 yr-1 in invaded wetlands. Plant invasion showed a significant tendency to increase CH4 uptakes from 2.95 to 3.64 kg CH4 ha-1 yr-1 in terrestrial ecosystems. Invasive plant species also significantly increased nitrous oxide (N2 O) emissions in grasslands from an average of 0.76 kg N2 O ha-1 yr-1 in native sites to 1.35 kg N2 O ha-1 yr-1 but did not affect N2 O emissions in forests or wetlands. Soil organic carbon, mean annual air temperature (MAT), and nitrogenous deposition (N_DEP) were the key factors responsible for the changes in wetland CH4 emissions due to plant invasion. The responses of terrestrial CH4 uptake rates to plant invasion were mainly driven by MAT, soil NH4 + , and soil moisture. Soil NO3 - , mean annual precipitation, and N_DEP affected terrestrial N2 O emissions in response to plant invasion. Our meta-analysis not only sheds light on the stimulatory effects of plant invasion on GHG emissions from wetland and terrestrial ecosystems but also improves our current understanding of the mechanisms underlying the responses of GHG emissions to plant invasion.

RevDate: 2022-06-06

Tarno H, Setiawan Y, Kusuma CB, et al (2021)

Diversity and Species Composition of Bark and Ambrosia Beetles Captured Using Ethanol Baited Traps on Different Hosts in East Java, Indonesia.

Zoological studies, 60:e55.

Bark and ambrosia beetles are a diverse group that causes widespread mortality of deciduous and coniferous trees. The present study aimed to investigate the species compositions and richnesses of bark and ambrosia beetles in six species of plant hosts in East Java, Indonesia. Bark and ambrosia beetles were sampled using bottle traps baited with ethanol. Studies were conducted at two sites of monoculture and polyculture systems for each host plant species. At each site, 20 ethanol-baited traps were deployed on a linear transect along the forest. Six host tree species examined were used, namely Tectona grandis (Teak), Syzygium aromaticum (Clove), Swietenia mahagoni (Mahogany), Pinus merkusii (Sumatran Pine), Paraserianthes falcataria (Moluccan Albizia), and Mangifera indica (Mango). The data were analyzed using R software. A total of 4823 beetles were collected, representing 26 ambrosia beetle and eight bark beetle species. The abundance of bark and ambrosia beetles was significantly highest at the sites of T. grandis (F = 13.88, P < 0.01). Xylosandrus crassiusculus showed a strong attraction to the ethanol lure and was the dominant beetle species (50.65% of the total number of individuals). The Shannon-Wiener diversity index of all beetles captured in this study was the highest in the S. mahogany polyculture (2.28) and the lowest in the T. grandis polyculture (0.47). According to Bray-Curtis analysis, the T. grandis monoculture and T. grandis polyculture had a high similarity value of bark and ambrosia beetle species compositions (91% similar). There were no significant differences between two cultural systems of host plants in the compositions of bark and ambrosia beetle species (ANOSIM, R = -0.1537, P = 0.961).

RevDate: 2022-06-06

Tucker AJ, Annis G, Elgin E, et al (2022)

Towards a framework for invasive aquatic plant survey design in Great Lakes coastal areas.

Management of biological invasions : international journal of applied research on biological invasions, 13(1):45-67.

At least 65 aquatic plant species have been identified as part of a surveillance list of non-native species that pose a threat to biodiversity and ecosystem services in the Laurentian Great Lakes. Early detection of these potentially invasive aquatic plants (IAP) could minimize impacts of novel incursions and facilitate successful eradication. We developed, implemented, and then adaptively refined a probabilistic boat-based sampling design that aimed to maximize the likelihood of detecting novel IAP incursions in large (400+ hectares) Great Lakes coastal areas. Surveys were conducted from 2017 to 2019 at five Great Lakes locations - St Joseph River (MI), Saginaw River (MI), Milwaukee (WI), Cleveland (OH), and the Detroit River (MI). Aquatic plant communities were characterized across the five sites, with a total of 61 aquatic plant species detected. One-fifth of the species detected in our surveys were non-native to the Great Lakes basin. Sample-based species rarefaction curves, constructed from detection data from all surveys combined at each location, show that the estimated sample effort required for high confidence (> 95%) detection of all aquatic plants at a site, including potentially invasive species, varies (< 100 sample units for Detroit River; > 300 sample units for Milwaukee, roughly equivalent to 6 to 18 days sampling effort, respectively). At least 70% of the estimated species pool was detected at each site during initial 3-day surveys. Leveraging information on detection patterns from initial surveys, including depth and species richness strata, improved survey efficiency and completeness at some sites, with detection of at least 80% of the estimated species pool during subsequent surveys. Based on a forest-based classification and regression method, a combination of just five variables explained 70% or more of the variation in observed richness at all sites (depth, fetch, percent littoral, distance to boat ramps and distance to marinas). We discuss how the model outcomes can be used to inform survey design for other Great Lakes coastal areas. The survey design we describe provides a useful template that could be adaptively improved for early detection of IAP in the Great Lakes.

RevDate: 2022-06-06

Wu W, Guo W, Ni G, et al (2022)

Expression Level Dominance and Homeolog Expression Bias Upon Cold Stress in the F1 Hybrid Between the Invasive Sphagneticola trilobata and the Native S. calendulacea in South China, and Implications for Its Invasiveness.

Frontiers in genetics, 13:833406 pii:833406.

The role of hybridization is significant in biological invasion, and thermotolerance is a trait critical to range expansions. The South American Sphagneticola trilobata is now widespread in South China, threatening the native S. calendulacea by competition and hybridization. Furthermore, upon formation, their F1 hybrid can quickly replace both parents. In this study, the three taxa were used as a model to investigate the consequences of hybridization on cold tolerance, particularly the effect of subgenome dominance in the hybrid. Upon chilling treatments, physiological responses and transcriptome profiles were compared across different temperature points to understand their differential responses to cold. While both parents showed divergent responses, the hybrid's responses showed an overall resemblance to S. calendulacea, but the contribution of homeolog expression bias to cold stress was not readily evident in the F1 hybrid possibly due to inherent bias that comes with the sampling location. Our findings provided insights into the role of gene expression in differential cold tolerance, and further contribute to predicting the invasive potential of other hybrids between S. trilobata and its congeners around the world.

RevDate: 2022-06-06

Lowie A, De Kegel B, Wilkinson M, et al (2022)

Is vertebral shape variability in caecilians (Amphibia: Gymnophiona) constrained by forces experienced during burrowing?.

The Journal of experimental biology pii:275610 [Epub ahead of print].

Caecilians are predominantly burrowing, elongate, limbless amphibians that remain relatively poorly studied. Although it has been suggested that the sturdy and compact skulls of caecilians are an adaptation to their head-first burrowing habits, no clear relationship between skull shape and burrowing performance appears to exist. However, the external forces encountered during burrowing are transmitted by the skull to the vertebral column, and as such, may impact vertebral shape. Additionally, the muscles that generate the burrowing forces attach onto the vertebral column and consequently may impact vertebral shape that way as well. Here, we explore the relationships between vertebral shape and maximal in vivo push forces in 13 species of caecilian amphibians. Our results show that the shape of the two most anterior vertebrae, as well as the shape of the vertebrae at 90% of the total body length, are not correlated with peak push forces. Conversely, the shape of the third vertebrae, and the vertebrae at 20% and 60% of the total body length, do show a relationship to push forces measured in vivo. Whether these relationships are indirect (external forces constraining shape variation) or direct (muscles forces constraining shape variation) remains unclear and will require quantitative studies of the axial musculature. Importantly, our data suggest that mid-body vertebrae may potentially be used as proxies to infer burrowing capacity in fossil representatives.

RevDate: 2022-06-06

Grzywacz A, Walczak K, Niewiadomska M, et al (2022)

Larval morphology and temperature-dependent development models of Fannia pusio (Wiedemann): a forensic indicator with expanding distribution.

Acta tropica pii:S0001-706X(22)00238-8 [Epub ahead of print].

Fannia pusio (Wiedemann) is originally from tropical and subtropical regions of the Americas, where it has repeatedly been collected from both animal carrion and human cadavers. This species is expanding its distributional range, and it has been introduced to Africa, Asia, Australia, Oceania, and Europe. Newly introduced species may be confused with native species of local arthropod necrophagous assemblages, which from a forensic entomology perspective may impact the accuracy of post-mortem interval (PMI) estimations based on insect evidence. In this work we aim to raise awareness among forensic entomologists of the potential benefits and risks associated with the expanding range of F. pusio. Morphology of all larval instars is documented with a combination of light, confocal laser scanning and scanning electron microscopy. Characters allowing identification from other forensically important Fanniidae are listed. Thermal requirements for the development of immature stages of F. pusio were examined under nine ambient temperatures. Models describing changes in larval body length over time were produced for eight different temperatures. The thermal summation constant (k) and developmental zero (Tmin) were calculated for six developmental events: hatching, first ecdysis, second ecdysis, wandering, pupariation, and eclosion.

RevDate: 2022-06-07

Singh JP, Kuang Y, Ploughe L, et al (2022)

Spotted knapweed (Centaurea stoebe) creates a soil legacy effect by modulating soil elemental composition in a semi-arid grassland ecosystem.

Journal of environmental management, 317:115391 pii:S0301-4797(22)00964-1 [Epub ahead of print].

Invasive plants such as spotted knapweed (Centaurea stoebe) are particularly detrimental to fragile ecosystems like semi-arid grasslands in the interior British Columbia, impacting aboveground and belowground ecology. Physical removal of C. stoebe has been one of the most popular invasive species management strategies, but the impact of C. stoebe removal on soil has hardly been studied. Here, we examine the legacy effect of C. stoebe on soil elemental composition and ecosystem function following its removal in the Lac Du Bios Grasslands Protected Area, British Columbia. First, we selected 40 paired C. stoebe invaded and control (uninvaded) plots and removed all vegetation from these plots. We planted Festuca campestris seedlings in these plots and harvested and weighed the biomass after four months. Additionally, we quantified total carbon and nitrogen in soil. We observed that C. stoebe invaded plots had significantly lower F. campestris biomass. Moreover, the total carbon and nitrogen content, and carbon/nitrogen ratio were significantly lower in C. stoebe invaded plots. We further analyzed 12 common soil elements and found the elemental composition was significantly different in C. stoebe invaded plots compared to controls. We investigated the impact of elemental composition on soil ecosystem functions (such as total soil carbon, total soil nitrogen, and F. campestris productivity). Our analysis revealed significant relationships amongst the elemental composition and total soil carbon and nitrogen, and F. campestris productivity. The results indicate that C. stoebe exerts a legacy effect by altering the soil elemental composition that may subsequently impacts soil ecosystem functions such as plant productivity and total carbon and nitrogen content.

RevDate: 2022-06-07

Escalas A, Auguet JC, Avouac A, et al (2022)

Shift and homogenization of gut microbiome during invasion in marine fishes.

Animal microbiome, 4(1):37.

Biological invasion is one of the main components of global changes in aquatic ecosystems. Unraveling how establishment in novel environments affects key biological features of animals is a key step towards understanding invasion. Gut microbiome of herbivorous animals is important for host health but has been scarcely assessed in invasive species. Here, we characterized the gut microbiome of two invasive marine herbivorous fishes (Siganus rivulatus and Siganus luridus) in their native (Red Sea) and invaded (Mediterranean Sea) ranges. The taxonomic and phylogenetic diversity of the microbiome increased as the fishes move away from the native range and its structure became increasingly different from the native microbiome. These shifts resulted in homogenization of the microbiome in the invaded range, within and between the two species. The shift in microbial diversity was associated with changes in its functions related with the metabolism of short-chain fatty acids. Altogether, our results suggest that the environmental conditions encountered by Siganidae during their expansion in Mediterranean ecosystems strongly modifies the composition of their gut microbiome along with its putative functions. Further studies should pursue to identify the precise determinants of these modifications (e.g. changes in host diet or behavior, genetic differentiation) and whether they participate in the ecological success of these species.

RevDate: 2022-06-03

Bowler CH, Shoemaker LG, Weiss-Lehman C, et al (2022)

Positive effects of exotic species dampened by neighborhood heterogeneity.

Ecology [Epub ahead of print].

It is well known that species interactions between exotic and native species are important for determining the success of biological invasions and how influential exotic species become in invaded communities. The strength and type of interactions between species can substantially vary, however, from negative and detrimental to minimal or even positive. Increasing evidence from the literature shows that exotic species have positive interactions with native species more often than originally thought. Gaps in our theory for how population growth is limited when interactions are positive, however, restrict our understanding of the mechanisms by which exotic 'facilitators' contribute to diversity maintenance in invaded systems. Here, we quantified interactions between seven native and four exotic (established non-native) common annual plant species in the highly diverse, York Gum woodlands of Western Australia. We used a Bayesian demographic modelling approach that allowed for interaction coefficients to be positive or negative, and explored key sources of variation in species responses to native and exotic neighbors at per capita (individual) and neighborhood levels. We observed positive per capita effects from exotic neighbors on exotic focal species as well as on several native focal species. However, all focal species were, on average, inhibited by their interaction neighborhood, when the variance in identity and abundance of observed neighbors was considered. At the neighborhood scale, exotic species were found to suppress all focal species, particularly those with high intrinsic fecundity. Our study demonstrates that within-neighborhood heterogeneity can regulate per capita positive effects of invaders - limiting runaway population growth of both natives and exotic invaders.

RevDate: 2022-06-01

Jiménez-Ramos R, Tomas F, Reynés X, et al (2022)

Carbon metabolism and bioavailability of dissolved organic carbon (DOC) fluxes in seagrass communities are altered under the presence of the tropical invasive alga Halimeda incrassata.

The Science of the total environment pii:S0048-9697(22)03422-2 [Epub ahead of print].

Seagrass beds act as blue carbon sinks globally as they enhance the trapping of recalcitrant (i.e., low biodegradability) organic carbon in their sediments. Recent studies also show that the recalcitrant fraction of the dissolved organic carbon (DOC) pool in seawater has an important role as long-term carbon sequestration in oceans. Although seagrasses are known for the large amount of DOC they export, little attention has been given to its biodegradability, which ultimately determinates its fate in the coastal carbon cycle. In turn, invasive algae are a major global concern in seagrass ecosystems since they can deeply modify their structure and functions, which may affect carbon metabolism and DOC release. This work assesses how the presence of Halimeda incrassata, an invasive tropical calcareous macroalga, modifies carbon metabolism and DOC fluxes in invaded areas dominated by the seagrass Cymodocea nodosa. Our results show that stands with the presence of this seagrass (i.e., both monospecific and mixed meadow) had the highest production values, acting as high DOC producers in both winter (mainly of labile DOC; DOCL) and summer (mainly as recalcitrant DOC; DOCR). In contrast, monospecific H. incrassata beds exhibited low production values, and the presence of this macroalga (either as monospecific beds or mixed with C. nodosa) triggered the shift from a net DOC-producing-system in summer (mainly DOCL) to a net DOC-consuming-system in winter. This work thus suggests that C. nodosa meadows have the potential to export a significant fraction of both labile and recalcitrant DOC, and that the spread of this invasive alga might decrease the C export capacity of seagrass meadows. Such shift would imply the reduction of a quick and efficient transfer of carbon and energy to higher trophic levels, and might reduce the blue carbon potential of seagrasses as dissolved form in the water column.

RevDate: 2022-06-01

Mowery MA, Anthony SE, Dorison AN, et al (2022)

Invasive Widow Spiders Perform Differently At Low Temperatures than Conspecifics from the Native Range.

Integrative and comparative biology pii:6596874 [Epub ahead of print].

Temperature challenges are one of the leading abiotic causes of success or failure of non-native species in a novel environment, and this is particularly true for low temperatures. Establishing and reproducing in a novel thermal environment can alter survival, behaviour, and traits related to fitness. It has been proposed that plasticity or adaptation of thermal tolerance may allow an introduced species to thrive, or that successful invaders may be those with a thermal breadth in their native habitat that encompasses their new environment. Here, we tested these hypotheses using native and invasive populations of Australian redback spiders (Latrodectus hasselti). We measured how exposure to temperatures (exposure to 15°C and 25°C, respectively) common to invasive and native range habitats affected behavioural and life-history traits and tradeoffs that may underlie fitness in an invasive population detected in 1995 in Japan and a native population from Australia. We found that the critical thermal minimum (CTmin) was higher in the invasive population from Japan than in the native population, but critical thermal maximum (CTmax) did not differ between populations. Compared to the invasive population, eggs from the native population had a longer development time and lower hatching success at 15°C. Both populations performed equally well at 25 °C, as measured by egg development time and hatching success. Invasive juveniles that developed at 15 °C were slower to explore a novel environment and less bold when tested at 25 °C vs. 15 °C. In comparison, the native population showed faster average exploration, with no differences in response at the two development or testing temperatures. Overall, L. hasselti from Japan maintained hatching success and development across a wider temperature range than the native population, indicating greater thermal breadth and higher behavioural plasticity. These results support the importance of plasticity in thermal tolerance and behaviour for a successful invasion under novel environmental temperatures.


RJR Experience and Expertise


Robbins holds BS, MS, and PhD degrees in the life sciences. He served as a tenured faculty member in the Zoology and Biological Science departments at Michigan State University. He is currently exploring the intersection between genomics, microbial ecology, and biodiversity — an area that promises to transform our understanding of the biosphere.


Robbins has extensive experience in college-level education: At MSU he taught introductory biology, genetics, and population genetics. At JHU, he was an instructor for a special course on biological database design. At FHCRC, he team-taught a graduate-level course on the history of genetics. At Bellevue College he taught medical informatics.


Robbins has been involved in science administration at both the federal and the institutional levels. At NSF he was a program officer for database activities in the life sciences, at DOE he was a program officer for information infrastructure in the human genome project. At the Fred Hutchinson Cancer Research Center, he served as a vice president for fifteen years.


Robbins has been involved with information technology since writing his first Fortran program as a college student. At NSF he was the first program officer for database activities in the life sciences. At JHU he held an appointment in the CS department and served as director of the informatics core for the Genome Data Base. At the FHCRC he was VP for Information Technology.


While still at Michigan State, Robbins started his first publishing venture, founding a small company that addressed the short-run publishing needs of instructors in very large undergraduate classes. For more than 20 years, Robbins has been operating The Electronic Scholarly Publishing Project, a web site dedicated to the digital publishing of critical works in science, especially classical genetics.


Robbins is well-known for his speaking abilities and is often called upon to provide keynote or plenary addresses at international meetings. For example, in July, 2012, he gave a well-received keynote address at the Global Biodiversity Informatics Congress, sponsored by GBIF and held in Copenhagen. The slides from that talk can be seen HERE.


Robbins is a skilled meeting facilitator. He prefers a participatory approach, with part of the meeting involving dynamic breakout groups, created by the participants in real time: (1) individuals propose breakout groups; (2) everyone signs up for one (or more) groups; (3) the groups with the most interested parties then meet, with reports from each group presented and discussed in a subsequent plenary session.


Robbins has been engaged with photography and design since the 1960s, when he worked for a professional photography laboratory. He now prefers digital photography and tools for their precision and reproducibility. He designed his first web site more than 20 years ago and he personally designed and implemented this web site. He engages in graphic design as a hobby.

Support this website:
Order from Amazon
We will earn a commission.

This is a must read book for anyone with an interest in invasion biology. The full title of the book lays out the author's premise — The New Wild: Why Invasive Species Will Be Nature's Salvation. Not only is species movement not bad for ecosystems, it is the way that ecosystems respond to perturbation — it is the way ecosystems heal. Even if you are one of those who is absolutely convinced that invasive species are actually "a blight, pollution, an epidemic, or a cancer on nature", you should read this book to clarify your own thinking. True scientific understanding never comes from just interacting with those with whom you already agree. R. Robbins

963 Red Tail Lane
Bellingham, WA 98226


E-mail: RJR8222@gmail.com

Collection of publications by R J Robbins

Reprints and preprints of publications, slide presentations, instructional materials, and data compilations written or prepared by Robert Robbins. Most papers deal with computational biology, genome informatics, using information technology to support biomedical research, and related matters.

Research Gate page for R J Robbins

ResearchGate is a social networking site for scientists and researchers to share papers, ask and answer questions, and find collaborators. According to a study by Nature and an article in Times Higher Education , it is the largest academic social network in terms of active users.

Curriculum Vitae for R J Robbins

short personal version

Curriculum Vitae for R J Robbins

long standard version

RJR Picks from Around the Web (updated 11 MAY 2018 )