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25 Jan 2021 at 01:33
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Bibliography on: Invasive Species


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RJR: Recommended Bibliography 25 Jan 2021 at 01:33 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: 2021-01-23

Denis F, A Serge (2021)

Hybridization and invasiveness in social insects - The good, the bad and the hybrid.

Current opinion in insect science pii:S2214-5745(21)00001-8 [Epub ahead of print].

Hybridization may help drive biological invasions by reducing Allee effects, increasing genetic variation, and generating novel adaptive genotypes/phenotypes. Social insects (ants, bees, wasps, and termites) are among the world's worst invasive species. In this review, we study the relationship between hybridization and invasiveness in social insects. We examine three types of hybridization based on the reproductive characteristics of first-generation hybrids. We discuss several examples of the association between hybridization and invasiveness, which are predominantly found in bees and termites. However, hybridization also occurs in several non-invasive species, and highly invasive species are not consistently associated with hybridization events, indicating that hybridization is not a main driver of invasiveness in social insects. We discuss why hybridization is not more commonly seen in invasive social insects.

RevDate: 2021-01-23

Hui C (2021)

Introduced species shape insular mutualistic networks.

Proceedings of the National Academy of Sciences of the United States of America, 118(5):.

RevDate: 2021-01-22

van der Marel A, Waterman JM, M López-Darias (2021)

Exploring the role of life history traits and introduction effort in understanding invasion success in mammals: a case study of Barbary ground squirrels.

Oecologia [Epub ahead of print].

Invasive species-species that have successfully overcome the barriers of transport, introduction, establishment, and spread-are a risk to biodiversity and ecosystem function. Introduction effort is one of the main factors underlying invasion success, but life history traits are also important as they influence population growth. In this contribution, we first investigated life history traits of the Barbary ground squirrel, Atlantoxerus getulus, a species with a very low introduction effort. We then studied if their invasion success was due to a very fast life history profile by comparing their life history traits to those of other successful invasive mammals. Next, we examined whether the number of founders and/or a fast life history influences the invasion success of squirrels. Barbary ground squirrels were on the fast end of the "fast-slow continuum", but their life history was not the only contributing factor to their invasion success, as the life history profile is comparable to other invasive species that do not have such a low introduction effort. We also found that neither life history traits nor the number of founders explained the invasion success of introduced squirrels in general. These results contradict the concept that introduction effort is the main factor explaining invasion success, especially in squirrels. Instead, we argue that invasion success can be influenced by multiple aspects of the new habitat or the biology of the introduced species.

RevDate: 2021-01-22

Bonthond G, Bayer T, Krueger-Hadfield SA, et al (2021)

The role of host promiscuity in the invasion process of a seaweed holobiont.

The ISME journal [Epub ahead of print].

Invasive species are co-introduced with microbiota from their native range and also interact with microbiota found in the novel environment to which they are introduced. Host flexibility toward microbiota, or host promiscuity, is an important trait underlying terrestrial plant invasions. To test whether host promiscuity may be important in macroalgal invasions, we experimentally simulated an invasion in a common garden setting, using the widespread invasive macroalga Agarophyton vermiculophyllum as a model invasive seaweed holobiont. After disturbing the microbiota of individuals from native and non-native populations with antibiotics, we monitored the microbial succession trajectories in the presence of a new source of microbes. Microbial communities were strongly impacted by the treatment and changed compositionally and in terms of diversity but recovered functionally by the end of the experiment in most respects. Beta-diversity in disturbed holobionts strongly decreased, indicating that different populations configure more similar -or more common- microbial communities when exposed to the same conditions. This decline in beta-diversity occurred not only more rapidly, but was also more pronounced in non-native populations, while individuals from native populations retained communities more similar to those observed in the field. This study demonstrates that microbial communities of non-native A. vermiculophyllum are more flexibly adjusted to the environment and suggests that an intraspecific increase in host promiscuity has promoted the invasion process of A. vermiculophyllum. This phenomenon may be important among invasive macroalgal holobionts in general.

RevDate: 2021-01-22

Tolo IE, Padhi SK, Williams K, et al (2021)

Susceptibility of Pimephales promelas and Carassius auratus to a strain of koi herpesvirus isolated from wild Cyprinus carpio in North America.

Scientific reports, 11(1):1985.

Cyprinid herpesvirus-3 (CyHV-3, syn. koi herpesvirus) is an important pathogen worldwide and a common cause of mass mortality events of wild common carp (Cyprinus carpio) in North America, however, reference strains and genomes obtained from wild carp are not available. Additionally, it is unclear if fishes in North America are susceptible to CyHV-3 infection due to incomplete susceptibility testing. Here we present the first North American type strain and whole-genome sequence of CyHV-3 isolated from wild carp collected from a lake with a history and recent incidence of carp mortality. Additionally, the strain was used in an in-vivo infection model to test the susceptibility of a common native minnow (Pimephales promelas) and goldfish (Carrasius auratus) which is invasive in North America. Detection of CyHV-3 DNA was confirmed in the tissues of a single fathead minnow but the same tissues were negative for CyHV-3 mRNA and samples from exposed fathead minnows were negative on cell culture. There was no detection of CyHV-3 DNA or mRNA in goldfish throughout the experiment. CyHV-3 DNA in carp tissues was reproducibly accompanied by the detection of CyHV-3 mRNA and isolation on cell culture. Additionally, environmental CyHV-3 DNA was detected on all tank filters during the study. These findings suggest that fathead minnows and goldfish are not susceptible to CyHV-3 infection and that detection of CyHV-3 DNA alone in host susceptibility trials should be interpreted with caution.

RevDate: 2021-01-22

Vázquez-Barrios V, Boege K, Sosa-Fuentes TG, et al (2021)

Ongoing ecological and evolutionary consequences by the presence of transgenes in a wild cotton population.

Scientific reports, 11(1):1959.

After 25 years of genetically modified cotton cultivation in Mexico, gene flow between transgenic individuals and their wild relatives represents an opportunity for analysing the impacts of the presence of novel genes in ecological and evolutionary processes in natural conditions. We show comprehensive empirical evidence on the physiological, metabolic, and ecological effects of transgene introgression in wild cotton, Gossypium hirsutum. We report that the expression of both the cry and cp4-epsps genes in wild cotton under natural conditions altered extrafloral nectar inducibility and thus, its association with different ant species: the dominance of the defensive species Camponotus planatus in Bt plants, the presence of cp4-epsps without defence role of Monomorium ebeninum ants, and of the invasive species Paratrechina longicornis in wild plants without transgenes. Moreover, we found an increase in herbivore damage to cp4-epsps plants. Our results reveal the influence of transgene expression on native ecological interactions. These findings can be useful in the design of risk assessment methodologies for genetically modified organisms and the in situ conservation of G. hirsutum metapopulations.

RevDate: 2021-01-22

Jug U, Naumoska K, I Vovk (2021)

(-)-Epicatechin-An Important Contributor to the Antioxidant Activity of Japanese Knotweed Rhizome Bark Extract as Determined by Antioxidant Activity-Guided Fractionation.

Antioxidants (Basel, Switzerland), 10(1): pii:antiox10010133.

The antioxidant activities of Japanese knotweed rhizome bark extracts, prepared with eight different solvents or solvent mixtures (water, methanol, 80% methanol(aq), acetone, 70% acetone(aq), ethanol, 70% ethanol(aq), and 90% ethyl acetate(aq)), were determined using a 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical-scavenging assay. Low half maximal inhibitory concentration (IC50) values (2.632-3.720 µg mL-1) for all the extracts were in the range of the IC50 value of the known antioxidant ascorbic acid at t0 (3.115 µg mL-1). Due to the highest extraction yield (~44%), 70% ethanol(aq) was selected for the preparation of the extract for further investigations. The IC50 value calculated for its antioxidant activity remained stable for at least 14 days, while the IC50 of ascorbic acid increased over time. The stability study showed that the container material was of great importance for the light-protected storage of the ascorbic acid(aq) solution in a refrigerator. Size exclusion-high-performance liquid chromatography (SEC-HPLC)-UV and reversed phase (RP)-HPLC-UV coupled with multistage mass spectrometry (MSn) were developed for fractionation of the 70% ethanol(aq) extract and for further compound identification, respectively. In the most potent antioxidant SEC fraction, determined using an on-line post-column SEC-HPLC-DPPH assay, epicatechin, resveratrol malonyl hexoside, and its in-source fragments (resveratrol and resveratrol acetyl hexoside) were tentatively identified by RP-HPLC-MSn. Moreover, epicatechin was additionally confirmed by two orthogonal methods, SEC-HPLC-UV and high-performance thin-layer chromatography (HPTLC) coupled with densitometry. Finally, the latter technique enabled the identification of (-)-epicatechin. (-)-Epicatechin demonstrated potent and stable time-dependent antioxidant activity (IC50 value ~1.5 µg mL-1) for at least 14 days.

RevDate: 2021-01-22
CmpDate: 2021-01-22

Tsai CL, Chu IH, Chou MH, et al (2020)

Rapid identification of the invasive fall armyworm Spodoptera frugiperda (Lepidoptera, Noctuidae) using species-specific primers in multiplex PCR.

Scientific reports, 10(1):16508.

The fall armyworm (FAW), Spodoptera frugiperda (Smith), is a major pest native to the Americas. A recent invasion of FAWs from Africa eastward to South Asia, the Indochina Peninsula, and mainland China has received much attention due to the considerable economic losses in agriculture. FAWs can rapidly colonise a new area, likely due to the wide range of host plants, good flying capability, and high egg production. Therefore, a convenient, quick, and accurate tool for FAW identification is urgently required to establish a FAW invasion management strategy. In this study, FAW-specific primers were designed to recognise FAWs on the basis of internal transcribed spacer 1 (ITS1). The results revealed the accurate FAW recognition of the three congeneric species and eight common corn lepidopteran pests, especially at their larval stage. Furthermore, species-specific primers have confirmed their efficacy by using 69 FAW specimens from Taiwan, Thailand, and the United States, with a 96% success rate, excluding 3 decayed specimens. By using the simple, reliable, and convenient FAW-specific primers, a pest management programme can be developed not only to reduce sequencing costs and experimental time from 2 days to 4 h, but eradicate the FAW as soon as it enters a new area.

RevDate: 2021-01-21

Fischer SM, Beck M, Herborg LM, et al (2021)

Managing aquatic invasions: Optimal locations and operating times for watercraft inspection stations.

Journal of environmental management, 283:111923 pii:S0301-4797(20)31848-X [Epub ahead of print].

Aquatic invasive species (AIS) cause significant ecological and economic damages around the world. A major spread mechanism for AIS is traffic of boaters transporting their watercraft from invaded to uninvaded waterbodies. To inhibit the spread of AIS, Canadian provinces and American states often set up watercraft inspection stations at roadsides, where potentially infested boats are screened for AIS and, if necessary, decontaminated. However, since budgets for AIS control are limited, watercraft inspection stations can only be operated at specific locations and daytimes. Though theoretical studies provide managers with general guidelines for AIS management, more specific results are needed to determine when and where watercraft inspections would be most effective. This is the subject of this paper. We show how linear integer programming techniques can be used to optimize watercraft inspection policies under budget constraints. We introduce our approach as a general framework and apply it to the prevention of the spread of zebra and quagga mussels (Dreissena spp.) to the Canadian province of British Columbia. We consider multiple scenarios and show how variations in budget constraints, propagule sources, and model uncertainty affect the optimal policy. Based on these results, we identify simple, generally applicable principles for optimal AIS management.

RevDate: 2021-01-21

Vozzo ML, Mayer-Pinto M, Bishop MJ, et al (2021)

Making seawalls multifunctional: The positive effects of seeded bivalves and habitat structure on species diversity and filtration rates.

Marine environmental research, 165:105243 pii:S0141-1136(20)31010-2 [Epub ahead of print].

The marine environment is being increasingly modified by the construction of artificial structures, the impacts of which may be mitigated through eco-engineering. To date, eco-engineering has predominantly aimed to increase biodiversity, but enhancing other ecological functions is arguably of equal importance for artificial structures. Here, we manipulated complexity through habitat structure (flat, and 2.5 cm, 5 cm deep vertical and 5 cm deep horizontal crevices) and seeding with the native oyster (Saccostrea glomerata, unseeded and seeded) on concrete tiles (0.25 m × 0.25 m) affixed to seawalls to investigate whether complexity (both orientation and depth of crevices) influences particle removal rates by suspension feeders and colonisation by different functional groups, and whether there are any ecological trade-offs between these functions. After 12 months, complex seeded tiles generally supported a greater abundance of suspension feeding taxa and had higher particle removal rates than flat tiles or unseeded tiles. The richness and diversity of taxa also increased with complexity. The effect of seeding was, however, generally weaker on tiles with complex habitat structure. However, the orientation of habitat complexity and the depth of the crevices did not influence particle removal rates or colonising taxa. Colonisation by non-native taxa was low compared to total taxa richness. We did not detect negative ecological trade-offs between increased particle removal rates and diversity and abundance of key functional groups. Our results suggest that the addition of complexity to marine artificial structures could potentially be used to enhance both biodiversity and particle removal rates. Consequently, complexity should be incorporated into future eco-engineering projects to provide a range of ecological functions in urbanised estuaries.

RevDate: 2021-01-21

Ng WL, Zhou Y, Zhou R, et al (2018)

Characterization of the complete chloroplast genome sequence of Sphagneticola calendulacea (Asteraceae).

Mitochondrial DNA. Part B, Resources, 3(2):1029-1030 pii:1511846.

Sphagneticola calendulacea is a valuable medicinal herb. With the spread of a congeneric invasive species Sphagneticola trilobata in South China, the already vulnerable S. calendulacea populations are being threatened further by natural hybridization with the invading species. In this study, we assembled and characterized the complete chloroplast genome of S. calendulacea as a resource for future studies on this species. The chloroplast genome was 151,748 bp in size, with a large single-copy (LSC) region of 83,270 bp, a small single-copy (SSC) region of 18,348 bp, separated by two inverted repeat (IR) regions of 25,065 bp each. A total of 134 genes were predicted. Phylogenetic analysis showed close relationship between S. calendulacea and Eclipta prostrata within the Heliantheae tribe.

RevDate: 2021-01-21

Zhou Y, Ng WL, Zhou R, et al (2018)

The complete chloroplast genome sequence of Sphagneticola trilobata (Asteraceae).

Mitochondrial DNA. Part B, Resources, 3(2):740-741 pii:1483767.

Sphagneticola trilobata is one of the world's worst invasive alien species. The paucity of genetic information for this species has made it difficult for studies on the underlying genetic mechanism of its invasiveness. Herein, we report the de novo chloroplast genome assembly of S. trilobata using Illumina whole-genome sequencing data. The chloroplast genome was 151,939 bp in length, with a large single copy (LSC) region of 83,405 bp, a small single copy (SSC) region of 18,448 bp, separated by two inverted repeat (IR) regions of 25,044 bp each. A total of 134 genes were annotated for the chloroplast genome assembly, including 86 protein-encoding genes. Phylogenetic analysis suggested close relationship between S. trilobata and Eclipta prostrata.

RevDate: 2021-01-21

Takahashi R, Okuyama H, Minoshima YN, et al (2018)

Complete mitochondrial DNA sequence of the alien hornet Vespa velutina (Insecta: Hymenoptera) invading Kyushu Island, Japan.

Mitochondrial DNA. Part B, Resources, 3(1):179-181 pii:1437823.

We analyzed the complete mitochondrial genome of the invasive Asian hornet Vespa velutina from Kyushu Island, Japan. The mitochondrial genome of V. velutina was identified as a circular molecule of 16,388 bp. We predicted that the genome contains 13 protein-coding genes (PCGs), 22 tRNA genes, and 2 rRNA genes, along with one A + T-rich control region. The average AT content is 81.68%. Molecular phylogenetic analysis using the 13 mitochondrial PCGs from 11 closely related taxa of Vespidae indicated that the V. velutina invading the Japanese Islands of Kyushu and Tsushima have a common origin.

RevDate: 2021-01-21

Woogeng IN, Coetzer WG, Etchu KA, et al (2017)

Current patterns of genetic diversity in indigenous and introduced species of land snails in Cameroon reflect isolation by distance, limited founder size and known evolutionary relationships.

Mitochondrial DNA. Part B, Resources, 2(2):375-380 pii:1347837.

The aim of this study was to gain molecular insights into patterns of genetic diversity in indigenous and introduced land snails in Cameroon. These species, Archachatina marginata and Achatina fulica, form an important source of protein in Cameroon, but widespread utilization may possibly impact natural patterns of genetic diversity of the indigenous species, while the introduced species may display signs of genetic drift. The evolutionary relationship between the indigenous and introduced species was also studied. Specimens were collected from seven sites in Cameroon. Genetic analyses using COI mitochondrial DNA data suggest that gene flow among the Ar. marginata populations screened follows a model of isolation by distance, and genetic diversity estimates for this species did not provide support for the hypothesis of loss of genetic diversity in areas of intense harvesting. Diversity in the introduced species was much lower, which is likely the signature of an introduction involving limited numbers.

RevDate: 2021-01-21

Takahashi R, Okuyama H, Kiyoshi T, et al (2017)

Complete mitochondrial DNA sequence of the invasive hornet Vespa velutina (Insecta, Hymenoptera) found in Japan.

Mitochondrial DNA. Part B, Resources, 2(1):143-144 pii:1289353.

In this study, we analyzed the complete mitochondrial genome of the invasive Asian hornet Vespa velutina from Japan. The mitochondrial genome of V. velutina was identified as a circular molecule of 16,765 bp, similar to that in other hornet species. It was predicted to contain 13 protein-coding, 20 tRNA, and two rRNA genes, along with one A + T-rich control region. The initiation codons ATC was found in one, ATG in four, ATT in five, and ATA in three genes, while TAA was the termination codon in all these genes. The average AT content of 13 protein-coding was 82%.

RevDate: 2021-01-21

Coates BS, CA Abel (2016)

The mitochondrial genome of the western bean cutworm, Striacosta albicosta (Lepidoptera: Noctuidae).

Mitochondrial DNA. Part B, Resources, 1(1):487-488 pii:1192499.

The complete 15,553 bp mitochondrial genome of the western bean cutworm, Stricosta albicosta, (Lepidoptera: Noctuidae) was assembled from paired end Illumina HiSeq2500 read data. Annotation showed 13 predicted protein coding genes (PCGs), 22 tRNAs and 2 rRNAs have an order and orientation typical of insect mitochondrial genomes, and the derived rearrangement of tRNA-Met, -Ile and -Gln upstream of nad2 as in other Lepidoptera. A 79.3% A + T content resulted in a bias for codons with A or T in the 3rd position, and prevalence of synonymous substitutions suggest the effects of purifying selection on the mitochondrial genome sequence. Two microsatellite repeat motifs, (CA)10(AT)19 and (AT)12, are respectively located in intergenic spaces between tRNA-Glu and -Phe and tRNA-Leu and 16S rRNA. Mitochondrial phylogenomics was able to resolve sub-families within the Noctuidae, and suggest analogous analyses may be applicable across other lepidopteran Families.

RevDate: 2021-01-21

Hua Y, Y Xu (2016)

Evolutionary status of the invasive American mink Neovison vison revealed by complete mitochondrial genome.

Mitochondrial DNA. Part B, Resources, 1(1):6-7 pii:1137794.

The American mink, Neovison vison, is native to North America and listed as one of the most widely distributed invasive species into the Eurasian mainland. Even though facing serious over-hunting and habitat degradation problems, this species has successfully dispersed into most areas of northeast China in the past decades, which may have a huge impact on local species composition and structure. We determined and annotated the whole mitochondrial DNA genome of the American mink N. vison to better understand the evolutionary relationship of this invasive species with other Mustelidae distributing in China. The complete mitogenome is 16 627 bp in length, includes 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes and one control region. We built the phylogenetic tree of American mink and other 10 most closely Mustelidae species.

RevDate: 2021-01-21

Clutton EA, Alurralde G, T Repolho (2021)

Early developmental stages of native populations of Ciona intestinalis under increased temperature are affected by local habitat history.

The Journal of experimental biology pii:jeb.233403 [Epub ahead of print].

Temperature modulates marine ectotherm physiology, influencing survival, abundance and species distribution. While native species could be susceptible to ocean warming, thermal tolerance might favour the spread of non-native species. Determining the success of invasive species in response to climate change is confounded by the cumulative, synergistic or antagonistic effects of environmental drivers, which vary at a geographical and temporal scale. Thus, an organism's acclimation or adaptive potential could play an important evolutionary role by enabling or conditioning species tolerance to stressful environmental conditions. We investigated developmental performance of early life stages of the ascidian Ciona intestinalis (derived from populations of anthropogenically-impacted and control sites) to an extreme weather event (i.e. marine heat wave). Fertilisation rate, embryo and larval development, settlement, metamorphosis success and juvenile heart beat rate were assessed as experimental endpoints. With the exception of fertilization and heart beat rates, temperature influenced all analysed endpoints. C. intestinalis derived from control sites were the most negatively affected by increased temperature conditions. Opposingly, C. intestinalis from anthropogenically impacted sites showed a positive response to thermal stress, with a higher proportion of larvae development, settlement and metamorphosis success being observed under increased temperature conditions. No differences were observed for heart beat rates between sampled populations and experimental temperature conditions. Moreover, interaction between temperature and populations was statistically significant for embryo and larvae development, and metamorphosis. We hypothesize that selection resulting from anthropogenic forcing could shape stress resilience of species in their native range and subsequently confer advantageous traits underlying their invasive potential.

RevDate: 2021-01-21
CmpDate: 2021-01-21

Yan Y, Schwirz J, MF Schetelig (2021)

Characterization of the Drosophila suzukii β2-tubulin gene and the utilization of its promoter to monitor sex separation and insemination.

Gene, 771:145366.

The Drosophila melanogaster β2-tubulin gene (Dm-β2t) controls the function of microtubules in the testis and sperm, and has been evaluated for use in biocontrol strategies based on the sterile insect technique, including sexing and the induction of male sterility. The spotted-wing Drosophila (Drosophila suzukii) is native to eastern Asia but has spread globally as an invasive pest of fruit crops, so biocontrol strategies are urgently required for this species. We therefore isolated the β2tubulin ortholog Ds-β2t from the USA laboratory strain of D. suzukii and confirmed the presence of functional motifs by aligning orthologs from multiple insects. The developmental expression profile of Ds-β2t was determined by RT-PCR using gene-specific primers and was similar to that of Dm-β2t. We then isolated the Ds-β2t promoter and used it to generate transgenic strains expressing a testis-specific fluorescent protein starting from the thirdinstar larvae. Efficient sexing was achieved based on fluorescence detection, and the transgenic males showed a similar survival rate to wild-type males. Fluorescence imaging and PCR were also used to confirm the insemination of wild-type females by transgenic males. We therefore confirm that D. suzukii strains expressing fluorescent markers under the control of the Ds-β2t promoter can be used for sexing and the confirmation of mating, and we discuss the wider potential of the Ds-β2t promoter in the context of genetic control strategies for D. suzukii.

RevDate: 2021-01-21
CmpDate: 2021-01-21

Keller EL, JJ Schall (2020)

A New Species of Monocystis (Apicomplexa: Gregarina: Monocystidae) from the Asian Invasive Earthworm Amynthas agrestis (Megascolecidae), with an Improved Standard for Monocystis Species Descriptions.

The Journal of parasitology, 106(6):735-741.

Monocystis perplexa n. sp., a parasite of an important invasive Japanese earthworm in North America, Amynthas agrestis, is described from a site in Vermont. An improved standard for Monocystis species descriptions is proposed including a standard nomenclature to reduce synonymies, a standard set of biometrics and shape descriptions for living cells, and a DNA genomic sequence for the 18S rRNA (∼1,700 base pairs). Comparing morphologies of Monocystis parasites in sympatric earthworm species indicates that M. perplexa is specific to A. agrestis in the study region. Also, polymerase chain reaction primers specific to M. perplexa amplified samples of A. agrestis earthworms taken from several sites in Japan. This suggests the parasite entered North America from Japan, the origin of the invasive Amynthas earthworm, and thus M. perplexa would be the first Monocystis described from the diverse Japanese Amynthas earthworms and the first from East Asia. Monocystis perplexa was found in every population of A. agrestis surveyed in Vermont, always reaching 100% prevalence by late summer (the host has an annual life cycle in Vermont). The 18S gene sequence differed from that of Monocystis agilis from the sympatric earthworm Lumbricus terrestris (the only other sequence available for Monocystis), and a genetic similarity tree places them closest among other gregarines. Many of the 95 described species of Monocystis are very similar in morphology (based on species descriptions), so the 18S gene can act as a barcode for Monocystis species and thus will help to eliminate both synonymies and reveal cryptic species.

RevDate: 2021-01-21
CmpDate: 2021-01-21

Turner RM, Plank MJ, Brockerhoff EG, et al (2020)

Considering unseen arrivals in predictions of establishment risk based on border biosecurity interceptions.

Ecological applications : a publication of the Ecological Society of America, 30(8):e02194.

Assessing species establishment risk is an important task used for informing biosecurity activities aimed at preventing biological invasions. Propagule pressure is a major contributor to the probability of invading species establishment; however, direct assessment of numbers of individuals arriving is virtually never possible. Inspections conducted at borders by biosecurity officials record counts of species (or higher-level taxa) intercepted during inspections, which can be used as proxies for arrival rates. Such data may therefore be useful for predicting species establishments, though some species may establish despite never being intercepted. We present a stochastic process-based model of the arrival-interception-establishment process to predict species establishment risk from interception count data. The model can be used to estimate the probability of establishment, both for species that were intercepted and species that had no interceptions during a given observation period. We fit the stochastic model to data on two insect families, Cerambycidae and Aphididae, that were intercepted and/or established in the United States or New Zealand. We also explore the effects of variation in model parameters and the inclusion of an Allee effect in the establishment probability. Although interception data sets contain much noise due to variation in inspection policy, interception effort and among-species differences in detectability, our study shows that it is possible to use such data for predicting establishments and distinguishing differences in establishment risk profile between taxonomic groups. Our model provides a method for predicting the number of species that have breached border biosecurity, including both species detected during inspections but also "unseen arrivals" that have never been intercepted, but have not yet established a viable population. These estimates could inform prioritization of different taxonomic groups, pathways or identification effort in biosecurity programs.

RevDate: 2021-01-21
CmpDate: 2021-01-21

Faria LC, MV Kitahara (2020)

Invasive corals hitchhiking in the Southwestern Atlantic.

Ecology, 101(8):e03066.

RevDate: 2021-01-19

Hofmeister NR, Werner SJ, IJ Lovette (2021)

Environmental correlates of genetic variation in the invasive European starling in North America.

Molecular ecology [Epub ahead of print].

Populations of invasive species that colonize and spread in novel environments may differentiate both through demographic processes and local selection. European starlings (Sturnus vulgaris) were introduced to New York in 1890 and subsequently spread throughout North America, becoming one of the most widespread and numerous bird species on the continent. Genome-wide comparisons across starling individuals and populations can identify demographic and/or selective factors that facilitated this rapid and successful expansion. We investigated patterns of genomic diversity and differentiation using reduced-representation genome sequencing (ddRADseq) of 17 winter-season sampling sites. Consistent with this species' high dispersal rate and rapid expansion history, we found low geographic differentiation and few FST outliers even at a continental scale. Despite starting from a founding population of ~180 individuals, North American starlings show only a moderate genetic bottleneck, and models suggest a dramatic increase in effective population size since introduction. In genotype-environment associations we found that ~200 single-nucleotide polymorphisms are correlated with temperature and/or precipitation against a background of negligible genome- and range-wide divergence. Given this evidence, we suggest that local adaptation in North American starlings may have evolved rapidly even in this wide-ranging and evolutionarily young system. This survey of genomic signatures of expansion in North American starlings is the most comprehensive to date and complements ongoing studies of world-wide local adaptation in these highly dispersive and invasive birds.

RevDate: 2021-01-19

Závorka L, Lassus R, Britton JR, et al (2020)

Phenotypic responses of invasive species to removals affect ecosystem functioning and restoration.

Global change biology, 26(10):5693-5704.

Reducing the abundances of invasive species by removals aims to minimize their ecological impacts and enable ecosystem recovery. Removal methods are usually selective, modifying phenotypic traits in the managed populations. However, there is little empirical evidence of how removal-driven changes in multiple phenotypic traits of surviving individuals of invasive species can affect ecosystem functioning and recovery. Overcoming this knowledge gap is highly relevant because individuals are the elemental units of ecological processes and so integrating individual-level responses into the management of biological invasions could improve their efficiency. Here we provide novel demonstration that removals by trapping, angling and biocontrol from lakes of the globally invasive crayfish Procambarus clarkii induced substantial changes in multiple phenotypic traits. A mesocosm experiment then revealed that these changes in phenotypic traits constrain recovery of basic ecosystem functions (decomposition of organic matter, benthic primary production) by acting in the opposite direction than the effects of reduced invader abundance. However, only minor ecological impacts of invader abundance and phenotypic traits variation remained a year after its complete eradication. Our study provides quantitative evidence to an original idea that removal-driven trait changes can dampen recovery of invaded ecosystems even when the abundance of invasive species is substantially reduced. We suggest that the phenotypic responses of invaders to the removal programme have strong effects on ecosystem recovery and should be considered within the management of biological invasions, particularly when complete eradication is not achievable.

RevDate: 2021-01-19

Stuart KC, Cardilini APA, Cassey P, et al (2020)

Signatures of selection in a recent invasion reveal adaptive divergence in a highly vagile invasive species.

Molecular ecology [Epub ahead of print].

A detailed understanding of population genetics in invasive populations helps us to identify drivers of successful alien introductions. Here, we investigate putative signals of selection in Australian populations of invasive common starlings, Sturnus vulgaris, and seek to understand how these have been influenced by introduction history. We used reduced representation sequencing to determine population structure, and identify Single Nucleotide Polymorphisms (SNPs) that are putatively under selection. We found that since their introduction into Australia, starling populations have become genetically differentiated despite the potential for high levels of dispersal, and that starlings have responded to selective pressures imposed by a wide range of environmental conditions across their geographic range. Isolation by distance appears to have played a strong role in determining genetic substructure across the starling's Australian range. Analyses of candidate SNPs that are putatively under selection indicated that aridity, precipitation and temperature may be important factors driving adaptive variation across the starling's invasive range in Australia. However, we also noted that the historic introduction regime may leave footprints on sites flagged as being under adaptive selection, and encourage critical interpretation of selection analyses in non-native populations.

RevDate: 2021-01-19

Soghigian J, Gloria-Soria A, Robert V, et al (2020)

Genetic evidence for the origin of Aedes aegypti, the yellow fever mosquito, in the southwestern Indian Ocean.

Molecular ecology, 29(19):3593-3606.

Aedes aegypti is among the best-studied mosquitoes due to its critical role as a vector of human pathogens and ease of laboratory rearing. Until now, this species was thought to have originated in continental Africa, and subsequently colonized much of the world following the establishment of global trade routes. However, populations of this mosquito on the islands in the southwestern Indian Ocean (SWIO), where the species occurs with its nearest relatives referred to as the Aegypti Group, have received little study. We re-evaluated the evolutionary history of Ae. aegypti and these relatives, using three data sets: nucleotide sequence data, 18,489 SNPs and 12 microsatellites. We found that: (a) the Aegypti Group diverged 16 MYA (95% HPD: 7-28 MYA) from its nearest African/Asian ancestor; (b) SWIO populations of Ae. aegypti are basal to continental African populations; (c) after diverging 7 MYA (95% HPD: 4-15 MYA) from its nearest formally described relative (Ae. mascarensis), Ae. aegypti moved to continental Africa less than 85,000 years ago, where it recently (<1,000 years ago) split into two recognized subspecies Ae. aegypti formosus and a human commensal, Ae. aegypti aegypti; (d) the Madagascar samples form a clade more distant from all other Ae. aegypti than the named species Ae. mascarensis, implying that Madagascar may harbour a new cryptic species; and (e) there is evidence of introgression between Ae. mascarensis and Ae. aegypti on Réunion, and between the two subspecies elsewhere in the SWIO, a likely consequence of recent introductions of domestic Ae. aegypti aegypti from Asia.

RevDate: 2021-01-19

Huang X, Liu B, Guo D, et al (2021)

Blackfordia virginica blooms shift the trophic structure to smaller size plankton in subtropical shallow waters.

Marine pollution bulletin, 163:111990 pii:S0025-326X(21)00024-2 [Epub ahead of print].

The hydromedusa Blackfordia virginica is an invasive species that has disrupted coastal marine food webs throughout the world. Here, we report the response of plankton community to B. virginica blooms in a subtropical lagoon in China. Chlorophyll-a concentrations increased after the peak of B. virginica abundance, which was coincident with high concentrations of ammonium. An increase of the biomass and composition of pico- and nano-phytoplankton during the bloom resulted from bottom-up effects due to the nutrients excreted by B. virginica. The average size and grazing rates of microzooplankton concurrently decreased. The negative correlation between the abundances of B. virginica and microzooplankton was accurately simulated by a generalized linear model and redundancy analysis. This study provided empirical evidence of the impacts of the B. virginica bloom on the food web and the mechanisms responsible for those effects. These impacts may lead to serious ecological and environmental consequences for the lagoonal ecosystem.

RevDate: 2021-01-18

Xie T, Wang Q, Ning Z, et al (2021)

Artificial modification on lateral hydrological connectivity promotes range expansion of invasive Spartina alterniflora in salt marshes of the Yellow River delta, China.

The Science of the total environment, 769:144476 pii:S0048-9697(20)38007-4 [Epub ahead of print].

'Invasibility', or the extent to which a habitat is prone to being invaded by plants, is a measure of the resistance of that ecosystem to biological invasion: a limited extent represents abiotic conditions unsuitable for invasion by invasive species; however, human activity can change that and make a habitat prone to rapid invasion. Field surveys and greenhouse experiments were carried out to explore, using spatial analysis, how a strong invader, namely Spartina alterniflora, is assisted by such activities as constructing levees and digging trenches, ditches, and pits in a tidal salt marsh. These activities changed the lateral hydrological connectivity of a salt marsh. The invasibility was then estimated based on the probability of seed dispersal and retention using the classical probabilistic method, and the rate of seedling emergence using threshold analysis. Changes in lateral hydrological connectivity led to more seeds of the invading species being retained, especially in high marshes, and promoted the emergence of its seedlings by making the soil more moist and less saline. The results suggest that changes in the lateral hydrological connectivity in a salt marsh can make it more prone to being invaded. The results have important implications for the control of invasive plants by limiting human activity and thereby regulating lateral hydrological connectivity in coastal ecosystems.

RevDate: 2021-01-19

Balzani P, Gozlan RE, PJ Haubrock (2020)

Overlapping niches between two co-occurring invasive fish: the topmouth gudgeon Pseudorasbora parva and the common bleak Alburnus alburnus.

Journal of fish biology, 97(5):1385-1392.

Invasive fish species impact aquatic ecosystems and modify native communities, often leading to a decline in local species. These ecological impacts include the transmission of pathogens, predation, competition as well as hybridization. Two invasive fish species, the common bleak Alburnus alburnus and the topmouth gudgeon Pseudorabora parva, have both been recently found co-occurring in several regions of southern Europe, such as the Italian Arno River. Nonetheless, the trophic relationships among invasive fish species, especially cyprinids, remain poorly understood, and no studies have reported the trophic interaction between these two species. This study compared length-weight relationship and used stomach content and stable isotope analysis of two co-occurring populations in the Arno River to characterize the growth and overlap of potential trophic niches. It also found similar allometric growth in both species, a wider generalist trophic niche for P. parva and a more specialized niche for A. alburnus. A considerable niche overlap was found, suggesting that feeding competition can occur if resources were to be limited. Moreover, the niche of P. parva was more likely to overlap with that of A. alburnus than vice versa, suggesting that P. parva can be considered as a potential over competitor. Nonetheless, the authors found in the overlapping populations no evidence of realized competition, probably avoided through a combination of fine-scale mechanisms. They also highlighted that these two invasive species can co-exist and share resources, at least in an open ecosystem like a river, thus potentially doubling up their trophic impact on local communities.

RevDate: 2021-01-18

Hartshorn JA, Coyle DR, RJ Rabaglia (2021)

Responses of Native and Non-native Bark and Ambrosia Beetles (Coleoptera: Curculionidae: Scolytinae) to Different Chemical Attractants: Insights From the USDA Forest Service Early Detection and Rapid Response Program Data Analysis.

Journal of economic entomology pii:6103849 [Epub ahead of print].

More than 60 non-native bark and ambrosia beetle species (Coleoptera: Curculionidae: Scolytinae) are established in North America and several have had severe negative impacts on ecosystems. Non-native scolytines can introduce fungi which may cause vascular wilts and compete with native fungi and lead to reductions in native species through host reduction. The Early Detection Rapid Response (EDRR) program was created by the USDA Forest Service in 2007 to detect non-native bark and ambrosia beetles and provide a baseline for tracking populations over time. This program has led to new collection records and increased communication among agencies to delimit non-native scolytine populations and perform appropriate management. Although insect responses to different lure types vary, it is unknown how different lures compare in attracting bark and ambrosia beetles. Our goal was to examine how lure combinations used in the EDRR program affect captures of bark and ambrosia beetle communities and to determine the most effective combination of lures for targeting non-native scolytines. The highest proportion of non-native scolytines was captured with ethanol, as was the greatest total number of species, and the most diverse beetle community. Traps with Ips (Coleoptera: Curculionidae) lures captured the highest proportion of native scolytines but the lowest total number of total species and was also the least diverse. Communities of scolytines differed significantly among lures, states, and years. While ethanol is an appropriate lure for generalist trapping and targeting a wide range of non-native bark and ambrosia beetles, more targeted lures are needed for monitoring certain species of non-natives.

RevDate: 2021-01-19

Taniwaki T, Hiroshima M, Imakita M, et al (2020)

Complete mitochondrial DNA sequence of the East Asian minnow, Pungtungia herzi (Actinopterygii: Cypriniformes).

Mitochondrial DNA. Part B, Resources, 5(3):3127-3129.

Some populations of the East Asian minnow Pungtungia herzi Herzenstein, 1892, which are naturally distributed in western Japan, have declined and are considered endangered. However, P. herzi has become a domestic invasive species in eastern Japan. Thus, knowledge of genetic features and phylogenetic relationships of P. herzi is important for conservation of this species and understanding its impact on ecosystems. We analyzed the complete mitochondrial genome using next generation sequencing of the East Asian minnow P. herzi from Yodo River, Osaka Prefecture, Japan. The mitochondrial genome of P. herzi consists of a circular molecule of 16,599 bp that includes 13 protein-coding genes (PCGs), 22 tRNA genes, two rRNA genes, and one control region. The heavy (H)-strand was predicted to have 12 PCGs, 14 tRNA, and two rRNA genes, while the light (L)-strand was predicted to contain one PCGs and eight tRNA genes. The average AT content was 57.68%. The genes ATP8 and ATP6, ATP6 and COIII, ND4L and ND4, and ND5 and ND6 shared seven, one, seven, and four nucleotides, respectively. The initiation codons ATG and GTG were found in 12 and one genes, respectively. The termination codons TAA, TAG, incomplete TA-, and single T-- were observed in nine, one, one, and two genes, respectively. All the tRNA genes possessed a cloverleaf secondary structure. The phylogenetic relationships inferred using 13 PCGs (based on the maximum likelihood) were consistent with previous studies that predicted interrelationships of Cypriniformes.

RevDate: 2021-01-19

Kim YC, Lee DH, Baek HJ, et al (2020)

Characteristic of complete mitochondrial genome and phylogenetic status of a muskrat, Ondatra zibethicus (Rodentia: Cricetidae) in South Korea.

Mitochondrial DNA. Part B, Resources, 5(3):2145-2146.

The complete mitochondrial genome of Muskrat, Ondatra zibethicus (Rodentia: Cricetidae) in Korea was sequenced for the first time using the next-generation sequencing method to understand its evolutionary relationship and to be helpful to establish a management plan. This mitogenome was 16,350 base pairs in length, containing 13 protein-coding genes, 22 transfer RNA genes, two ribosomal RNA genes, and one control region. Its overall A, C, G, and T contents were 32.0%, 26.9%, 12.6%, and 28.5%, respectively. A + T content (63.7%) was higher than G + C content (36.3%). We made the phylogenetic tree of muskrat and other 12 species of order Rodentia distributed in Korea.

RevDate: 2021-01-19

Hartnell College Genomics Group, Aguilar A, Ahumada TJ, et al (2020)

The complete mitochondrial and plastid genomes of the invasive marine red alga Caulacanthus okamurae (Caulacanthaceae, Rhodophyta) from Moss Landing, California, USA.

Mitochondrial DNA. Part B, Resources, 5(3):2067-2069.

Caulacanthus okamurae is an invasive red alga that forms extensive mats in sheltered marine habitats around the world. To determine its genomic structure and genetic relationship to native and other non-native populations of C. okamurae, high-throughput sequencing analysis was performed on an introduced specimen from Bennett Slough, Moss Landing, California, USA. Assembly of 23,146,595 filtered 150 bp paired-end Illumina sequencing reads yielded its complete mitogenome (GenBank accession MT193839) and plastid genome (GenBank accession MT193838). The mitogenome is 25,995 bp in length and contains 50 genes. The plastid genome is 173,516 bp and contains 234 genes. Comparison of the organellar chromosomes to other Gigartinales revealed a high-level of gene synteny. BLAST analysis of marker sequences (rbcL, cox1, cox2) of C. okamurae from Moss Landing identified four identical DNA sequences: one from a specimen from a native population of C. okamurae from South Korea and three from specimens representing invasive populations from France, Spain, and the USA. These genetic results confirm the presence of C. okamurae in central California, USA, and represent the first complete mitogenome and plastid genome from the Caulacanthaceae.

RevDate: 2021-01-19

Jouladeh-Roudbar A, Ghanavi HR, I Doadrio (2020)

Ichthyofauna From Iranian Freshwater: Annotated Checklist, Diagnosis, Taxonomy, Distribution and Conservation Assessment.

Zoological studies, 59:e21.

This is an annotated checklist of all the recognized and named taxa of freshwater fishes in Iran. It documents recent changes and controversies in the nomenclature and includes primary synonyms updated from the Jouladeh-Roudbar et al. (2015b) checklist. We provide an updated comprehensive listing of taxonomy, diagnostic and meristic characters, names, and conservation status, including detailed distribution maps. We strive to record the most recent justified taxonomic assignment in a hierarchical framework, providing annotations, including alternative possible arrangements, for some proposed changes. We provide common English and Persian names, and detail distributional data for all taxa, listing occurrence by basins, including indications of native, endemic, and translocated populations. We used the IUCN Red List Categories and Criteria for classifying species at high risk of global extinction. This checklist consists of 274 recognized species in 100 genera, 33 families, 20 orders and 3 classes. We also report and confirm for the first time the presence of seven species from Iran's basins: Aphanius kruppi, Capoeta kaput, Luciobarbus conocephalus, Oxynoemacheilus veyselorum, O. gyndes, O. hanae and Squalius latus. The confirmed freshwater fishes of Iran comprise 264 species in 97 genera, 33 families, 20 orders and 3 classes. The 241 endemic and native fish species can be divided into the following conservation statuses: 1 Extinct in the Wild (EW), 17 Critically Endangered (CR), 12 Endangered (EN), 15 Vulnerable (VU), 9 Near Threatened (NT), 148 Least Concern (LC) and 39 Data Deficient (DD). Forty-four fish species (18.3% of the 241 species listed) are officially regarded as globally Threatened (Critically Endangered [CR], Endangered [EN], or Vulnerable [VU]). These numbers and percentages of Threatened species have increased since the last checklist.

RevDate: 2021-01-18
CmpDate: 2021-01-18

Hogg CJ, Lea MA, Gual Soler M, et al (2020)

Protect the Antarctic Peninsula - before it's too late.

Nature, 586(7830):496-499.

RevDate: 2021-01-16

Cai M, Lin X, Peng J, et al (2021)

Why Is the Invasive Plant Sphagneticola trilobata More Resistant to High Temperature than Its Native Congener?.

International journal of molecular sciences, 22(2): pii:ijms22020748.

Climate change and invasive alien species threaten biodiversity. High temperature is a worrying ecological factor. Most responses of invasive plants aimed at coping with adversity are focused on the physiological level. To explore the molecular mechanisms underlying the response of an invasive plant (Sphagneticola trilobata L.) to high temperature, using a native species (Sphagneticola calendulacea L.) as the control, relevant indicators, including photosynthetic pigments, gas exchange, chlorophyll fluorescence, the antioxidant system, and related enzyme-coding genes were measured. The results showed that the leaves of S. calendulacea turned yellow, photosynthetic pigment content (Chl a, Chl b, Car, Chl) decreased, gas exchange (Pn) and chlorophyll fluorescence parameters (Fv/Fm, ΦPSII) decreased under high temperature. It was also found that high temperature caused photoinhibition and a large amount of ROS accumulated, resulting in an increase in MDA and relative conductivity. Antioxidant enzymes (including SOD, POD, CAT, and APX) and antioxidants (including flavonoids, total phenols, and carotenoids) were decreased. The qPCR results further showed that the expression of the PsbP, PsbA, and RubiscoL, SOD, POD, CAT, and APX genes was downregulated, which was consistent with the results of physiological data. Otherwise, the resistance of S. trilobata to high temperature was better than that of S. calendulacea, which made it a superior plant in the invasion area. These results further indicated that the gradual warming of global temperature will greatly accelerate the invasion area of S. trilobata.

RevDate: 2021-01-16

Tang Y, Li Q, Xiang L, et al (2021)

First Report on Megaselia scalaris Loew (Diptera: Phoridae) Infestation of the Invasive Pest Spodoptera frugiperda Smith (Lepidoptera: Noctuidae) in China.

Insects, 12(1): pii:insects12010065.

The invasive pest Spodoptera frugiperda first emerged in China in January 2019 and has, to date, migrated to 29 provinces and municipalities in China, causing heavy crop damage in large areas. As a response to this invasive species from the environment, some indigenous natural enemies have been discovered and reported after S. frugiperda invasion. In this paper, parasitic flies were collected and identified from S. frugiperda collected in the Yunnan, Guangxi, and Henan provinces and the Chongqing municipality in China. By using both conventional and molecular approaches, we were able to show that all the parasitic flies of S. frugiperda identified in the four regions were Megaselia. scalaris, and that they attacked the pest larvae and pupae. This is the first report on an indigenous Chinese Megaselia species that has parasitic ability against the invasive pest S. frugiperda, potentially providing new ideas for pest control in China.

RevDate: 2021-01-16

Ðurović G, Alawamleh A, Carlin S, et al (2021)

Liquid Baits with Oenococcus oeni Increase Captures of Drosophila suzukii.

Insects, 12(1): pii:insects12010066.

The spotted-wing drosophila (SWD), Drosophila suzukii Matsumura (Diptera: Drosophilidae), native to Eastern Asia, is an invasive alien species in Europe and the Americas, where it is a severe pest of horticultural crops, including soft fruits and wine grapes. The conventional approach to controlling infestations of SWD involves the use of insecticides, but the frequency of application for population management is undesirable. Consequently, alternative strategies are urgently needed. Effective and improved trapping is important as an early risk detection tool. This study aimed to improve Droskidrink® (DD), a commercially available attractant for SWD. We focused on the chemical and behavioral effects of adding the bacterium Oenococcus oeni (Garvie) to DD and used a new trap design to enhance the effects of attractive lures. We demonstrate that microbial volatile compounds produced by O. oeni are responsible for the increase in the attractiveness of the bait and could be later utilized for the development of a better trapping system. Our results showed that the attractiveness of DD was increased up to two-fold by the addition of commercially available O. oeni when combined with an innovative trap design. The new trap-bait combination increased the number of male and especially female catches at low population densities.

RevDate: 2021-01-15

Lopes AS, Pulido-Murillo EA, Lopez-Hernandez D, et al (2021)

First report of Melanoides tuberculata (Mollusca: Thiaridae) harboring a xiphidiocercaria in Brazil: A new parasite introduced in the Americas?.

Parasitology international pii:S1383-5769(21)00003-9 [Epub ahead of print].

Xiphidiocercariae were found in the invasive snail Melanoides tuberculata collected during a malacological survey in Ceará-Mirim, State of Rio Grande do Norte, Northeastern Brazil in November 2018 and submitted to morphological and molecular analyses. The morphology revealed similarities between the larvae here reported for the first time in M. tuberculata from Brazil and other xiphidiocercariae described in thiarid snails from Asia and Africa. Phylogenetic analysis based on 28S and ITS-2 sequences revealed that the larvae correspond to an unidentified species of the family Lecithodendriidae. Aspects related to the morphology and taxonomy of xiphidiocercariae found in M. tuberculata are briefly discussed. It is possible that the parasite here reported is a newly introduced species transmitted by M. tuberculata in the American continent.

RevDate: 2021-01-15

Popovic I, L Bernatchez (2021)

Uncovering endemism in a lake of invasive species introgression.

Species distributions are rapidly being altered by human globalisation and movement. As species are moved across biogeographic boundaries, human-mediated secondary contacts between historically allopatric taxa may promote hybridisation between closely related native and introduced species. The outcomes of hybridisation are diverse from strong reproductive barriers to gene flow to genome-wide admixture that may enhance (Fitzpatrick et al., 2010; Mesgaran et al., 2016; Valencia-Montoya et al., 2020) or impede (Kovach et al., 2016) invasive spread. For native species, introgressive hybridisation may disassemble locally adapted genomes, and in extreme cases, extensive asymmetric introgression may lead to the 'genomic extinction' of endemic diversity (Rhymer & Simberloff, 1996; Todesco et al., 2016). Undoubtedly, introgressive hybridisation can rapidly alter the evolution of introduced and endemic populations. This is a major conservation issue (Leitwein, Duranton, Rougemont, Gagnaire, & Bernatchez, 2020), with the greatest potential consequences on small, range-restricted native populations where introduced species may reach higher relative densities (Currat, Ruedi, Petit, & Excoffier, 2008). In this issue of Molecular Ecology, Blackwell et al. (2020) explore the history of divergence and admixture between the highly invasive Nile tilapia, Oreochromis niloticus, and a recently discovered Oreochromis lineage that is endemic to the coastal lakes of southern Tanzania. Oreochromis tilapias belong to the African cichlids and the most diverse family of vertebrates (Cichlidae), with almost 2000 species inhabiting the Great Lakes and river environments of Eastern Africa (Kocher, 2004; McGee et al., 2020). By analysing previously unrecognised cichlid diversity from southern lakes, Blackwell et al. (2020) provide novel evidence for how introgressive hybridisation with introduced species can alter native genetic makeup, illustrating the potential susceptibility of Tanzania's endemic biodiversity to genetic threats from introduced taxa.

RevDate: 2021-01-15

Hernández FA, Carr AN, Milleson MP, et al (2021)

Dispersal and Land Cover Contribute to Pseudorabies Virus Exposure in Invasive Wild Pigs.

EcoHealth [Epub ahead of print].

We investigated the landscape epidemiology of a globally distributed mammal, the wild pig (Sus scrofa), in Florida (U.S.), where it is considered an invasive species and reservoir to pathogens that impact the health of people, domestic animals, and wildlife. Specifically, we tested the hypothesis that two commonly cited factors in disease transmission, connectivity among populations and abundant resources, would increase the likelihood of exposure to both pseudorabies virus (PrV) and Brucella spp. (bacterial agent of brucellosis) in wild pigs across the Kissimmee Valley of Florida. Using DNA from 348 wild pigs and sera from 320 individuals at 24 sites, we employed population genetic techniques to infer individual dispersal, and an Akaike information criterion framework to compare candidate logistic regression models that incorporated both dispersal and land cover composition. Our findings suggested that recent dispersal conferred higher odds of exposure to PrV, but not Brucella spp., among wild pigs throughout the Kissimmee Valley region. Odds of exposure also increased in association with agriculture and open canopy pine, prairie, and scrub habitats, likely because of highly localized resources within those land cover types. Because the effect of open canopy on PrV exposure reversed when agricultural cover was available, we suggest that small-scale resource distribution may be more important than overall resource abundance. Our results underscore the importance of studying and managing disease dynamics through multiple processes and spatial scales, particularly for non-native pathogens that threaten wildlife conservation, economy, and public health.

RevDate: 2021-01-15

Jones L, Brennan GL, Lowe A, et al (2021)

Shifts in honeybee foraging reveal historical changes in floral resources.

Communications biology, 4(1):37.

Decreasing floral resources as a result of habitat loss is one of the key factors in the decline of pollinating insects worldwide. Understanding which plants pollinators use is vital to inform the provision of appropriate floral resources to help prevent pollinator loss. Using a globally important pollinator, the honeybee, we show how changes in agricultural intensification, crop use and the spread of invasive species, have altered the nectar and pollen sources available in the UK. Using DNA metabarcoding, we analysed 441 honey samples from 2017 and compared these to a nationwide survey of honey samples from 1952. We reveal that shifts in major plants foraged by honeybees are driven by changes in the availability of these plants within the landscape. Improved grasslands are the most widespread habitat type in the UK, and management changes within this habitat have the greatest potential to increase floral resource availability.

RevDate: 2021-01-15

Delgado-Acevedo J, Zamorano A, DeYoung RW, et al (2021)

Genetic Population Structure of Wild Pigs in Southern Texas.

Animals : an open access journal from MDPI, 11(1): pii:ani11010168.

Wild pigs (Sus scrofa) alter ecosystems, affect the economy, and carry diseases that can be transmitted to livestock, humans, and wildlife. Understanding wild pig movements and population structure data, including natural population boundaries and dispersal, may potentially increase the efficiency and effectiveness of management actions. We trapped, conducted aerial shootings, and hunted wild pigs from 2005 to 2009 in southern Texas. We used microsatellites to assist large-scale applied management. We quantify broad-scale population structure among 24 sites across southern Texas by computing an overall Fst value, and a Bayesian clustering algorithm both with and without considering the spatial location of samples. At a broad geographic scale, pig populations displayed a moderate degree of genetic structure (Fst = 0.11). The best partition for number of populations, based on 2nd order rate of change of the likelihood distribution, was K = 10 genetic clusters. The spatially explicit Bayesian clustering algorithm produced similar results, with minor differences in designation of admixed sites. We found evidence of past (and possibly ongoing) translocations; many populations were admixed. Our original goal was to identify landscape features, such as barriers or dispersal corridors, that could be used to aid management. Unfortunately, the extensive admixture among clusters made this impossible. This research shows that large-scale management of wild pigs may be necessary to achieve control and ameliorate damages. Reduction or cessation of translocations is necessary to prevent human-mediated dispersion of wild pigs.

RevDate: 2021-01-14

Yang X, Wyckhuys KAG, Jia X, et al (2021)

Fall armyworm invasion heightens pesticide expenditure among Chinese smallholder farmers.

Journal of environmental management, 282:111949 pii:S0301-4797(21)00011-6 [Epub ahead of print].

Invasive species are a prominent feature of global change. Aside from their direct impacts on biodiversity and ecosystem functioning, invasive crop pests routinely trigger environmentally-disruptive actions e.g., unguided applications of synthetic pesticides. Since 2016, the polyphagous fall armyworm (FAW, Spodoptera frugiperda J.E. Smith) has rapidly spread across Africa and Asia, impacting millions of hectares of agricultural crops. Upon its invasion of Yunnan (China) in late 2018, S. frugiperda attained outbreak population levels and inflicted important feeding damage in smallholder-managed maize crops. In this study, we show how local maize growers rely primarily on pesticides for FAW management and employ these products at 3-fold higher application frequencies as compared to 2018. Local reliance upon high-risk compounds (i.e., pyrethroids, organophosphates) decreased over time, with a respective 100% and 62% farmers using these compounds in 2018 versus 27% and 5% in 2020. Conversely, 71% and 95% farmers used new, selective compounds such as emamectin benzoate and chlorfenapyr by 2020. The full cost of pesticide-based crop protection increased from US $81 per hectare and season in 2018 to $276 in 2020. In farmer-managed fields, FAW infestation levels averaged 8.3 larvae per 100 plants and thus remained below economic injury levels (EILs) as established in other countries. Farmers' use of two or more pesticide sprays per season likely was not economically justified. Our work demonstrates how the FAW invasion has altered pest management regimes in Yunnan's maize crop, deepening farmers' pesticide dependency, and potentially exacerbating its burden on household budgets. Sustainable pest management schemes urgently need to be devised for smallholder maize systems in China and across the FAW invaded range.

RevDate: 2021-01-14

Li FL, Zhong L, Wen W, et al (2021)

Do distribution and expansion of exotic invasive Asteraceae plants relate to leaf construction cost in a man-made wetland?.

Marine pollution bulletin, 163:111958 pii:S0025-326X(20)31077-8 [Epub ahead of print].

Exotic species especially Asteraceae plants severely invade wetlands in Shenzhen Bay, an important part of the coast wetland in Guangdong-Hong Kong-Macau Bay Area, China. However, the reasons causing their expansion are unclear. The leaf traits and expansion indices of six invasive Asteraceae plants from the Overseas Chinese Town (OCT) wetland were studied and the results showed that nearly 45% of the total plant species (31 out of 69 species) in the OCT wetland, belonging to 15 families and 27 genera, were exotic invasive species. The expansion indices of six Asteraceae species negatively correlated with their leaf construction cost based on mass (CCM), caloric values and carbon concentration, but their relations with ash content were positive. Multiple linear regression analysis revealed that CCM was the most important factor affecting the expansion of an exotic species, indicating CCM may be an important reason causing the expansion of exotic species in coastal wetlands.

RevDate: 2021-01-14

Abia WA, Montgomery H, Nugent AP, et al (2021)

Tropane alkaloid contamination of agricultural commodities and food products in relation to consumer health: Learnings from the 2019 Uganda food aid outbreak.

Comprehensive reviews in food science and food safety, 20(1):501-525.

Tropane alkaloids (TAs) are secondary plant metabolites derived mainly from Solanaceae plant families, with the most virulent invasive species being Datura stramonium. Datura stramonium commonly grows in cereal fields and produce TAs (e.g., hyoscyamine and scopolamine) which may accidentally contaminate cereals (and cereal-based foods) at occasionally high levels. Dietary exposure to TAs can be toxic and depending on the dose ingested can cause outcomes ranging from anticholinergic effects to acute poisoning and death. In 2019, 315 adults became ill and another five adults died in Uganda following consumption of a "Super Cereal" (a fortified blended food) that was later confirmed to be contaminated by TAs-a scenario which provoked this holistic review on TAs in foodstuffs. Thus, this article provides information on the history, development, occurrences, exposures, and human legislative and health benchmarks for TAs. It describes control strategies for reducing TA contamination of agricultural commodities and resultant health implications following consumption of TA contaminated foodstuffs. Adequate application of food safety control measures (including maximum limits) and good practices, from the start of cereal cultivation through to the final stages of manufacturing of food products can aid in the reduction of seeing toxic plants including D. stramonium in cereal fields.

RevDate: 2021-01-14

Tabashnik BE, Liesner LR, Ellsworth PC, et al (2021)

Transgenic cotton and sterile insect releases synergize eradication of pink bollworm a century after it invaded the United States.

Proceedings of the National Academy of Sciences of the United States of America, 118(1):.

Invasive organisms pose a global threat and are exceptionally difficult to eradicate after they become abundant in their new habitats. We report a successful multitactic strategy for combating the pink bollworm (Pectinophora gossypiella), one of the world's most invasive pests. A coordinated program in the southwestern United States and northern Mexico included releases of billions of sterile pink bollworm moths from airplanes and planting of cotton engineered to produce insecticidal proteins from the bacterium Bacillus thuringiensis (Bt). An analysis of computer simulations and 21 y of field data from Arizona demonstrate that the transgenic Bt cotton and sterile insect releases interacted synergistically to reduce the pest's population size. In Arizona, the program started in 2006 and decreased the pest's estimated statewide population size from over 2 billion in 2005 to zero in 2013. Complementary regional efforts eradicated this pest throughout the cotton-growing areas of the continental United States and northern Mexico a century after it had invaded both countries. The removal of this pest saved farmers in the United States $192 million from 2014 to 2019. It also eliminated the environmental and safety hazards associated with insecticide sprays that had previously targeted the pink bollworm and facilitated an 82% reduction in insecticides used against all cotton pests in Arizona. The economic and social benefits achieved demonstrate the advantages of using agricultural biotechnology in concert with classical pest control tactics.

RevDate: 2021-01-14

Subedi IP, Budha PB, Bharti H, et al (2020)

An updated checklist of Nepalese ants (Hymenoptera, Formicidae).

ZooKeys, 1006:99-136 pii:58808.

The location of Nepal in the Central Himalaya promotes high habitat and species diversity. Ant diversity is likely high, but there have been few studies of the diversity and distribution of ants in Nepal. Here we present an updated checklist list of Nepalese ants that includes 128 named species in 48 genera and eight subfamilies. Among these species, 21 species have a type locality from Nepal, nine species are endemic to Nepal, and three are introduced species. We add six new ant records for Nepal, namely Harpegnathos venator, Monomorium pharaonis, Nylanderia bourbonica, Odontoponera denticulata, Polyrhachis tyrannica and Pseudoneoponera bispinosa. The checklist presents distribution records for Nepalese ant species and provides comparisons with the neighboring countries of China and India.

RevDate: 2021-01-14
CmpDate: 2021-01-13

Mao R, Shabbir A, S Adkins (2021)

Parthenium hysterophorus: A tale of global invasion over two centuries, spread and prevention measures.

Journal of environmental management, 279:111751.

Ever since parthenium weed (Parthenium hysterophorus L.) first left its native range more than two centuries ago, this noxious herb has now invaded 46 countries and territories. The weed has expanded its range from a couple of islands in 18th Century through 11 minor and eight major introductions around the world. Segmented regression analyses confirmed introductions and revealed that the weed has spread fastest in developing countries, especially after the 1950s in Asia and Africa. A review of historical records, research papers and reports suggests that while border traffic (36%) and unchecked imports (seeds 16%, other commodities 17%) have resulted in the majority of international introductions, local spread has been achieved through multiple pathways, including roads and vehicles, by water and wind, through contaminated seed feed lots and floral bouquets. The high proportion of adjacent counties (51%) and oversea islands (5%) over the unknown origins (32%) or directly from the native range (12%) reveal a steady and predictable international spread pattern. Prevention of spread by management was first practised in Australia, then followed by other five countries. Containment barriers were set up, legislation on biosecurity imposed, and management plans based on early detection and eradication were executed; and these measures have been effective. Awareness within international research groups is raising, however, insufficient coordination between invaded countries has occurred to date, with policies yet to be formalised and executed to prevent the spread and impact of this weed.

RevDate: 2021-01-13

Kołodziej-Sobocińska M, Tokarska M, Zalewska H, et al (2021)

Digestive tract nematode infections in non-native invasive American mink with the first molecular identification of Molineus patens.

International journal for parasitology. Parasites and wildlife, 14:48-52 pii:S2213-2244(20)30116-4.

Parasites may negatively affect hosts condition, especially when infection intensity is high. Species introduced to a new habitat are often less exposed to a parasite pressure but may accumulate parasites in time. American mink (Neovison vison) introduced to Europe, Asia, and South America is an example of such invasive species. We analysed nematode prevalence and digestive tract infection intensity in 796 feral American mink from Poland. The analyses were performed separately for stomach, duodenum, small intestine and large intestine. Parasite species identification was performed using molecular methods based on highly conserved nuclear 18S rRNA gene and supplemented with morphological analysis. In total, we collected 26,852 nematodes and 98.6% of them were isolated from mink stomachs. We found positive association between infection intensity in stomach and other parts of digestive tract. Nematode prevalence was estimated at 63.8% and average infection intensity per one American mink at 52.9 (range from 1 to 1118). If the stomach results were theoretically and intentionally omitted the prevalence was 5 times lower (12.7%) and infection intensity 14 times lower (3.7; range 1-50). We identified two nematode species in digestive tracts of American mink: Aonchotheca putorii and Molineus patens. The 18S rRNA gene sequence of Molineus patens has been reported for the first time. The results showed that Aonchotheca putorii is a dominating nematode in the invasive American mink and that it inhabits stomach intensively and preferably.

RevDate: 2021-01-13

Woo S, Lee D, Cho YC, et al (2021)

Differential responses to fertilization and competition among invasive, noninvasive alien, and native Bidens species.

Ecology and evolution, 11(1):516-525 pii:ECE37071.

Comparative studies of invasive, noninvasive alien, and native congenic plant species can identify plant traits that drive invasiveness. In particular, functional traits associated with rapid growth rate and high fecundity likely facilitate invasive success. As such traits often exhibit high phenotypic plasticity, characterizing plastic responses to anthropogenic environmental changes such as eutrophication and disturbance is important for predicting the invasive success of alien plant species in the future. Here, we compared trait expression and phenotypic plasticity at the species level among invasive, noninvasive alien, and native Bidens species. Plants were grown under nutrient addition and competition treatments, and their functional, morphological, and seed traits were examined. Invasive B. frondosa exhibited higher phenotypic plasticity in most measured traits than did the alien noninvasive B. pilosa or native B. bipinnata. However, differential plastic responses to environmental treatments rarely altered the rank of trait values among the three Bidens species, except for the number of inflorescences. The achene size of B. frondosa was larger, but its pappus length was shorter than that of B. pilosa. Two species demonstrated opposite plastic responses of pappus length to fertilization. These results suggest that the plasticity of functional traits does not significantly contribute to the invasive success of B. frondosa. The dispersal efficiency of B. frondosa is expected to be lower than that of B. pilosa, suggesting that long-distance dispersal is likely not a critical factor in determining invasive success.

RevDate: 2021-01-13

Ho PT, Nguyen HQ, Kern EMA, et al (2021)

Locomotor responses to salt stress in native and invasive mud-tidal gastropod populations (Batillaria).

Ecology and evolution, 11(1):458-470 pii:ECE37065.

Plasticity in salt tolerance can be crucial for successful biological invasions of novel habitats by marine gastropods. The intertidal snail Batillaria attramentaria, which is native to East Asia but invaded the western shores of North America from Japan 80 years ago, provides an opportunity to examine how environmental salinity may shape behavioral and morphological traits. In this study, we compared the movement distance of four B. attramentaria populations from native (Korea and Japan) and introduced (United States) habitats under various salinity levels (13, 23, 33, and 43 PSU) during 30 days of exposure in the lab. We sequenced a partial mitochondrial CO1 gene to infer phylogenetic relationships among populations and confirmed two divergent mitochondrial lineages constituting our sample sets. Using a statistical model-selection approach, we investigated the effects of geographic distribution and genetic composition on locomotor performance in response to salt stress. Snails exposed to acute low salinity (13 PSU) reduced their locomotion and were unable to perform at their normal level (the moving pace of snails exposed to 33 PSU). We did not detect any meaningful differences in locomotor response to salt stress between the two genetic lineages or between the native snails (Japan vs. Korea populations), but we found significant locomotor differences between the native and introduced groups (Japan or Korea vs. the United States). We suggest that the greater magnitude of tidal salinity fluctuation at the US location may have influenced locomotor responses to salt stress in introduced snails.

RevDate: 2021-01-12

Savidge JA, Seibert TF, Kastner M, et al (2021)

Lasso locomotion expands the climbing repertoire of snakes.

Current biology : CB, 31(1):R7-R8.

The diverse ways and environments in which animals move are correlated with morphology1, but morphology is not sufficient to predict how animals move because behavioral innovations can create new capacities. We document a new mode of snake locomotion - 'lasso locomotion' - that allows the brown treesnake (Boiga irregularis) to ascend much larger smooth cylinders than any previously known behavior. This lasso locomotion may facilitate exploiting resources that might otherwise be unobtainable and contribute to the success and impact of this highly invasive species. VIDEO ABSTRACT.

RevDate: 2021-01-12

Wendlandt C, Helliwell E, Roberts M, et al (2021)

Decreased coevolutionary potential and increased symbiont fecundity during the biological invasion of a legume-rhizobium mutualism.

Evolution; international journal of organic evolution [Epub ahead of print].

Although most invasive species engage in mutualism, we know little about how mutualism evolves as partners colonize novel environments. Selection on cooperation and standing genetic variation for mutualism traits may differ between a mutualism's invaded and native ranges, which could alter cooperation and coevolutionary dynamics. To test for such differences, we compare mutualism traits between invaded- and native-range host-symbiont genotype combinations of the weedy legume, Medicago polymorpha, and its nitrogen-fixing rhizobium symbiont, Ensifer medicae, which have co-invaded North America. We find that mutualism benefits for plants are indistinguishable between invaded- and native-range symbioses. However, rhizobia gain greater fitness from invaded-range mutualisms than from native-range mutualisms, and this enhancement of symbiont fecundity could increase the mutualism's spread by increasing symbiont availability during plant colonization. Furthermore, mutualism traits in invaded-range symbioses show lower genetic variance and a simpler partitioning of genetic variance between host and symbiont sources, compared to native-range symbioses. This suggests that biological invasion has reduced mutualists' potential to respond to coevolutionary selection. Additionally, rhizobia bearing a locus (hrrP) that can enhance symbiotic fitness have more exploitative phenotypes in invaded-range than in native-range symbioses. These findings highlight the impacts of biological invasion on the evolution of mutualistic interactions. This article is protected by copyright. All rights reserved.

RevDate: 2021-01-12

Vaas J, Driessen PPJ, Giezen M, et al (2021)

Moving from Latent to Manifest Problem: Trajectories Across Scientific and Public Salience of Invasive Alien Species.

Environmental management [Epub ahead of print].

Who worries first about an invasive alien species: scientists or the general public, or do both become concerned simultaneously? Taking thirteen invasive alien species in the Netherlands, this article reconstructs the development of their public and scientific salience: the attention they attracted and the knowledge about them. Salience was assessed from the number of publications from 1997 onwards in the LexisNexis newspaper database and Scopus scientific database. Three trajectories were derived for a species to move from being a latent problem with low salience toward a manifest status with high public and scientific salience. In the most common trajectory, scientific salience increased first, followed by an increase in public salience. We probed the merit of this concept of trajectories by examining the action undertaken for a representative species of the trajectories. We assigned each of these three species a code for inertia and inaction based on the content of a hundred newspaper articles and all available government documents. Knowing the scientific and public salience of these species clarifies why the actions to deal with them differed even though from an ecological perspective they warranted similar attention. The typology of public and scientific salience and the problem trajectories developed in this article together offer a structured approach for understanding an invasive alien species and provide pointers for engaging a community in managing that species.

RevDate: 2021-01-12

Andres KJ, Sethi SA, Lodge DM, et al (2021)

Nuclear eDNA estimates population allele frequencies and abundance in experimental mesocosms and field samples.

Molecular ecology [Epub ahead of print].

Advances in environmental DNA (eDNA) methodologies have led to improvements in the ability to detect species and communities in aquatic environments, yet the majority of studies emphasize biological diversity at the species level by targeting variable sites within the mitochondrial genome. Here, we demonstrate that eDNA approaches also have the capacity to detect intraspecific diversity in the nuclear genome, allowing for assessments of population-level allele frequencies and estimates of the number of genetic contributors in an eDNA sample. Using a panel of microsatellite loci developed for the round goby (Neogobius melanostomus), we tested the similarity between eDNA-based and individual tissue-based estimates of allele frequencies from experimental mesocosms and in a field-based trial. Subsequently, we used a likelihood-based DNA mixture framework to estimate the number of unique genetic contributors in eDNA samples and in simulated mixtures of alleles. In both mesocosm and field samples, allele frequencies from eDNA were highly correlated with allele frequencies from genotyped round goby tissue samples, indicating nuclear markers can be reliably amplified from water samples. DNA mixture analyses were able to estimate the number of genetic contributors from mesocosm eDNA samples and simulated mixtures of DNA from up to 58 individuals, with the degree of positive or negative bias dependent on the filtering scheme of low-frequency alleles. With this study we document the application of eDNA and multiple amplicon-based methods to obtain intraspecific nuclear genetic information and estimate the absolute abundance of a species in eDNA samples. With proper validation, this approach has the potential to advance noninvasive survey methods to characterize populations and detect population-level genetic diversity.

RevDate: 2021-01-12

Xia S, Wang W, Song Z, et al (2021)

Spartina alterniflora invasion controls organic carbon stocks in coastal marsh and mangrove soils across tropics and subtropics.

Global change biology [Epub ahead of print].

Coastal wetlands are among the most productive ecosystems and store large amounts of organic carbon (C) - the so termed "blue carbon". However, wetlands in the tropics and subtropics have been invaded by smooth cordgrass (Spartina alterniflora) affecting storage of blue C. To understand how S. alterniflora affects SOC stocks, sources, stability, and their spatial distribution, we sampled soils along a 2500 km coastal transect encompassing tropical to subtropical climate zones. This included 216 samplings within three coastal wetland types: a marsh (Phragmites australis) and two mangroves (Kandelia candel and Avicennia marina). Using δ13 C, C: nitrogen (N) ratios and lignin biomarker composition we traced changes in the sources, stability and storage of SOC in response to S. alterniflora invasion. The contribution of S. alterniflora-derived C up to 40 cm accounts for 5.6%, 23% and 12% in the P. australis, K. candel and A. marina communities, respectively, with a corresponding change in SOC storage of +3.5, -14 and -3.9 t C ha-1 . SOC storage did not follow the trend in aboveground biomass from the native to invasive species, or with vegetation types and invasion duration (7-15 years). SOC storage decreased with increasing mean annual precipitation (1000-1900 mm) and temperature (15.3-23.4 ℃). Edaphic variables in P. australis marshes remained stable after S. alterniflora invasion and so, their effects on SOC content were absent. In mangrove wetlands, however, electrical conductivity, total N and phosphorus, pH and active silicon were the main factors controlling SOC stocks. Mangrove wetlands were most strongly impacted by S. alterniflora invasion and efforts are needed to focus on restoring native vegetation. By understanding the mechanisms and consequences of invasion by S. alterniflora, changes in blue C sequestration can be predicted to optimize storage can be developed.

RevDate: 2021-01-12

Vizentin-Bugoni J, Sperry JH, Kelley JP, et al (2021)

Ecological correlates of species' roles in highly invaded seed dispersal networks.

Proceedings of the National Academy of Sciences of the United States of America, 118(4):.

Ecosystems with a mix of native and introduced species are increasing globally as extinction and introduction rates rise, resulting in novel species interactions. While species interactions are highly vulnerable to disturbance, little is known about the roles that introduced species play in novel interaction networks and what processes underlie such roles. Studying one of the most extreme cases of human-modified ecosystems, the island of O'ahu, Hawaii, we show that introduced species there shape the structure of seed dispersal networks to a greater extent than native species. Although both neutral and niche-based processes influenced network structure, niche-based processes played a larger role, despite theory predicting neutral processes to be predominantly important for islands. In fact, ecological correlates of species' roles (morphology, behavior, abundance) were largely similar to those in native-dominated networks. However, the most important ecological correlates varied with spatial scale and trophic level, highlighting the importance of examining these factors separately to unravel processes determining species contributions to network structure. Although introduced species integrate into interaction networks more deeply than previously thought, by examining the mechanistic basis of species' roles we can use traits to identify species that can be removed from (or added to) a system to improve crucial ecosystem functions, such as seed dispersal.

RevDate: 2021-01-12

Wagner DL, Fox R, Salcido DM, et al (2021)

A window to the world of global insect declines: Moth biodiversity trends are complex and heterogeneous.

Proceedings of the National Academy of Sciences of the United States of America, 118(2):.

Moths are the most taxonomically and ecologically diverse insect taxon for which there exist considerable time-series abundance data. There is an alarming record of decreases in moth abundance and diversity from across Europe, with rates varying markedly among and within regions. Recent reports from Costa Rica reveal steep cross-lineage declines of caterpillars, while other sites (Ecuador and Arizona, reported here) show no or only modest long-term decreases over the past two decades. Rates of decline for dietary and ecological specialists are steeper than those for ecologically generalized taxa. Additional traits commonly associated with elevated risks include large wingspans, small geographic ranges, low dispersal ability, and univoltinism; taxa associated with grasslands, aridlands, and nutrient-poor habitats also appear to be at higher risk. In temperate areas, many moth taxa limited historically by abiotic factors are increasing in abundance and range. We regard the most important continental-scale stressors to include reductions in habitat quality and quantity resulting from land-use change and climate change and, to a lesser extent, atmospheric nitrification and introduced species. Site-specific stressors include pesticide use and light pollution. Our assessment of global macrolepidopteran population trends includes numerous cases of both region-wide and local losses and studies that report no declines. Spatial variation of reported losses suggests that multiple stressors are in play. With the exception of recent reports from Costa Rica, the most severe examples of moth declines are from Northern Hemisphere regions of high human-population density and intensive agriculture.

RevDate: 2021-01-12
CmpDate: 2021-01-12

Suzuki T, T Ikeda (2020)

Invasive raccoon management systems and challenges in regions with active control.

BMC ecology, 20(1):68.

BACKGROUND: The raccoon (Procyon lotor) is an invasive, non-native species in Japan. Throughout the country, it causes significant agricultural damage and negatively affects native biodiversity. Most of the responsibility for raccoon management lies with local government, and there are still many challenges to be overcome. Although raccoon populations have not been eradicated, intensive control campaigns such as focus on the early stages of invasion have controlled raccoons in some regions. To improve the national management of raccoons, we conducted a survey on raccoon management systems in local government departments considered to solve the challenges recognized in many areas. During 2014 and 2015, we surveyed three different municipal departments about raccoon management measures. The semi-structured interview survey covered two topics: (1) the situation leading up to the current management system; (2) the current management system.

RESULTS: Our results describe the scope and methods used in raccoon management. The government staff managed raccoons using monitoring, employing a variety of methods, a range of budgets, and various role divisions. The management practices are similar in that they share a sense of taking precautions, collaborating with stakeholders, understanding that adequate methods must be used, and obtaining support from experts.

CONCLUSIONS: Our case studies reveal the challenges in raccoon management faced by local government officers in regions with active control. The management systems and methods that we surveyed seemed to be effective in solving problems in both developed and undeveloped areas.

RevDate: 2021-01-13
CmpDate: 2021-01-13

Wang J, Zhao M, Zhang J, et al (2021)

Characterization and utilization of biochars derived from five invasive plant species Bidens pilosa L., Praxelis clematidea, Ipomoea cairica, Mikania micrantha and Lantana camara L. for Cd2+ and Cu2+ removal.

Journal of environmental management, 280:111746.

Exotic invasive plants endanger the integrity of agricultural and natural systems throughout the world. Thus, the development of cost-effective and economic application of invasive plants is warranted. Here, we characterized fifteen biochars derived from five invasive plants at different temperatures (300, 500, and 700 °C) by determining their yield, ash content, pH, CEC, surface area, elementary composition, functional groups, and mineral composition. We conducted batch adsorption experiments to investigate the adsorption capacity and efficiency for Cd2+ and Cu2+ in wastewater. Our results suggest that all invasive plants are appropriate for biochar production, temperature and plant species had interacting effects on biochar properties, and the biochars pyrolyzed at 500 and 700 °C exhibited high metal adsorption capacity in neutral (pH = 7) solutions. The adsorption kinetics can be explained adequately by a pseudo-second-order model. BBC500 (Bidens pilosa L. derived biochar at 500 °C) and MBC500 (Mikania micrantha) exhibited higher metal equilibrium adsorption capacities (38.10 and 38.02 mg g-1 for Cd2+, 20.01 and 20.10 mg g-1 for Cu2+) and buffer abilities to pH than other biochars pyrolyzed at 500 °C. The Langmuir model was a better fit for IBC500 (Ipomoea cairica), MBC500, and LBC500 (Lantana camara L.) compared to the Freundlich model, whereas the opposite was true for BBC500 and PBC500 (Praxelis clematidea). These results suggest that the adsorption of metals by IBC500, MBC500, and LBC500 was mainly monolayer adsorption, while that by BBC500 and PBC500 was mainly chemical adsorption. Our results are important for the utilization and control of invasive plants as well as the decontamination of aqueous pollution.

RevDate: 2021-01-12
CmpDate: 2021-01-12

Zhang G, Bai J, Tebbe CC, et al (2021)

Spartina alterniflora invasions reduce soil fungal diversity and simplify co-occurrence networks in a salt marsh ecosystem.

The Science of the total environment, 758:143667.

Soil fungal communities drive diverse ecological processes and are critical in maintaining ecosystems' stability, but the effects of plant invasion on soil fungal diversity, community composition, and functional groups are not well understood. Here, we investigated soil fungal communities in a salt marsh ecosystem with both native (Suaeda salsa) and exotic (Spartina alterniflora) species in the Yellow River Delta. We characterized fungal diversity based on the PCR-amplified Internal Transcribed Spacer 2 (ITS2) DNA sequences from soil extracted total DNA. The plant invasion evidently decreased fungal richness and phylogenetic diversity and significantly altered the taxonomic community composition (indicated by the permutation test, P < 0.001). Co-occurrence networks between fungal species showed fewer network links but were more assembled because of the high modularity after the invasion. As indicated by the fungal Bray-Curtis and weighted UniFrac distances, the fungal community became homogenized with the invasion. FUNGuild database analyses revealed that the invaded sites had a higher proportion of saprophytic fungi, suggesting higher organic matter decomposition potential with the invasion. The plant invasion dramatically inhibited the growth of pathogenic fungi, which may facilitate the expansion of invasive plants in the intertidal habitats. Soil pH and salinity were identified as the most important edaphic factors in shaping the fungal community structures in the context of Spartina alterniflora invasion. Overall, this study elucidates the linkage between plant invasion and soil fungal communities and poses potential consequences for fungal contribution to ecosystem function, including the decomposition of soil organic substrates.

RevDate: 2021-01-13
CmpDate: 2021-01-13

Kerr JR, Vowles AS, Crabb MC, et al (2021)

Selective fish passage: Restoring habitat connectivity without facilitating the spread of a non-native species.

Journal of environmental management, 279:110908.

River managers are challenged to address two key threats to freshwater biodiversity. The first is the effects of habitat fragmentation by instream structures, such as dams and weirs, that disrupt migrations and impact species distributions. The second is the impact of non-native species on native species and ecological processes. However, mitigating anthropogenic habitat fragmentation through the installation of passage facilities can facilitate the invasion and spread of non-native species. This study compared the potential of two existing low-cost fish passage technologies designed for sloping weirs, a cylindrical bristle cluster (CBC) array and horizontally oriented studded tiles, to facilitate upstream movement of native European fish while preventing dispersal of non-native American signal crayfish (Pacifastacus leniusculus); thus providing a selective fish passage solution. Crayfish movement and passage was experimentally quantified at a Crump weir installed in a recirculating flume under two velocity regimes (low and high), without (control) and with the addition of either a CBC array or studded tiles. Results were compared to passage efficacy (PE) data for native fish species for both technologies (existing data). Most (84.4%) crayfish were active during the trials, exhibiting frequent up and downstream movements below the weir. During control conditions under the high velocity regime, high velocities (ca. 2.39 m s-1) prevented crayfish reaching the foot of the weir (PE: 0%). Under the low velocity regime, relatively low velocities (ca. 0.74 m s-1) at the weir crest prevented most crayfish from passing (PE: 10-16%). Crayfish movement speed and total distance moved were lower under the high than the low velocity regime. Neither fish pass technology improved crayfish maximum distance of ascent on the downstream weir face or PE under either velocity regime. Under comparable conditions to the high velocity regime tested here, previous studies have shown both technologies improve PE for native fish. Hence, both CBC arrays and studded tiles would likely function as suitable selective fish passes where the conservation objective is not to aid the spread of non-native crayfish. Additional passage inhibiting technologies will be required at sites where complete blockage of crayfish movement is required.

RevDate: 2021-01-12
CmpDate: 2021-01-12

Lebouvier M, Lambret P, Garnier A, et al (2020)

Spotlight on the invasion of a carabid beetle on an oceanic island over a 105-year period.

Scientific reports, 10(1):17103.

The flightless beetle Merizodus soledadinus, native to the Falkland Islands and southern South America, was introduced to the sub-Antarctic Kerguelen Islands in the early Twentieth Century. Using available literature data, in addition to collecting more than 2000 new survey (presence/absence) records of M. soledadinus over the 1991-2018 period, we confirmed the best estimate of the introduction date of M. soledadinus to the archipelago, and tracked subsequent changes in its abundance and geographical distribution. The range expansion of this flightless insect was initially slow, but has accelerated over the past 2 decades, in parallel with increased local abundance. Human activities may have facilitated further local colonization by M. soledadinus, which is now widespread in the eastern part of the archipelago. This predatory insect is a major threat to the native invertebrate fauna, in particular to the endemic wingless flies Anatalanta aptera and Calycopteryx moseleyi which can be locally eliminated by the beetle. Our distribution data also suggest an accelerating role of climate change in the range expansion of M. soledadinus, with populations now thriving in low altitude habitats. Considering that no control measures, let alone eradication, are practicable, it is essential to limit any further local range expansion of this aggressively invasive insect through human assistance. This study confirms the crucial importance of long term biosurveillance for the detection and monitoring of non-native species and the timely implementation of control measures.

RevDate: 2021-01-11

Ferreira V, Figueiredo A, Graça MAS, et al (2021)

Invasion of temperate deciduous broadleaf forests by N-fixing tree species - consequences for stream ecosystems.

Biological reviews of the Cambridge Philosophical Society [Epub ahead of print].

Biological invasions are a major threat to biodiversity and ecosystem functioning. Forest invasion by alien woody species can have cross-ecosystem effects. This is especially relevant in the case of stream-riparian forest meta-ecosystems as forest streams depend strongly on riparian vegetation for carbon, nutrients and energy. Forest invasion by woody species with dissimilar characteristics from native species may be particularly troublesome. The invasion of temperate deciduous broadleaf forests with low representation of nitrogen (N)-fixing species by N-fixers has the potential to induce ecosystem changes at the stream level. Although effects of tree invasion on stream ecosystems have been under assessed, knowledge of native and invasive tree characteristics allows prediction of invasion effects on streams. Here we present a conceptual model to predict the effects of forest invasion by alien N-fixing species on streams, using as a background the invasion of temperate deciduous broadleaf forests by leguminous Acacia species, which are among the most aggressive invaders worldwide. Effects are discussed using a trait-based approach to allow the model to be applied to other pairs of invaded ecosystem-invasive species, taking into account differences in species traits and environmental conditions. Anticipated effects of N-fixing species invasions include changes in water quality (increase in N concentration) and quantity (decrease in flow) and changes in litter input characteristics (altered diversity, seasonality, typology, quantity and quality). The magnitude of these changes will depend on the magnitude of differences in species traits, the extent and duration of the invasion and stream characteristics (e.g. basal nutrient concentration). The extensive literature on effects of nutrient enrichment of stream water, water scarcity and changes in litter input characteristics on aquatic communities and processes allows prediction of invasion effects on stream structure and function. The magnitude of invasion effects on aquatic communities and processes may, however, depend on interactions among different pathways (e.g. effects mediated by increases in stream nutrient concentration may contrast with those mediated by decreases in water availability or by decreases in litter nutritional quality). A review of the literature addressing effects of increasing cover of N-fixing species on streams suggests a wide application of the model, while it highlights the need to consider differences in the type of system and species when making generalizations. Changes induced by N-fixing species invasion on streams can jeopardize multiple ecosystem services (e.g. good quality water, hydroelectricity, leisure activities), with relevant social and economic consequences.

RevDate: 2021-01-11

He Y, Hou H, Wang S, et al (2021)

From waste of marine culture to natural patch in cardiac tissue engineering.

Bioactive materials, 6(7):2000-2010 pii:S2452-199X(20)30336-4.

Sea squirt, as a highly invasive species and main biofouling source in marine aquaculture, has seriously threatened the biodiversity and aquaculture economy. On the other hand, a conductive biomaterial with excellent biocompatibility, and appropriate mechanical property from renewable resources is urgently required for tissue engineering patches. To meet these targets, we presented a novel and robust strategy for sustainable development aiming at the marine pollution via recycling and upgrading the waste biomass-sea squirts and serving as a renewable resource for functional bio-scaffold patch in tissue engineering. We firstly demonstrated that the tunic cellulose derived natural self-conductive scaffolds successfully served as functional cardiac patches, which significantly promote the maturation and spontaneous contraction of cardiomyocytes both in vitro and enhance cardiac function of MI rats in vivo. We believe this novel, feasible and "Trash to Treasure" strategy to gain cardiac patches via recycling the waste biomass must be promising and beneficial for marine environmental bio-pollution issue and sustainable development considering the large-scale consumption potential for tissue engineering and other applications.

RevDate: 2021-01-11

Piroddi C, Colloca F, AC Tsikliras (2020)

The living marine resources in the Mediterranean Sea Large Marine Ecosystem.

Environmental development pii:S2211-4645(20)30077-4 [Epub ahead of print].

The Mediterranean Large Marine Ecosystem (Med-LME) is a heterogeneous system that, despite its oligotrophic nature, has high diversity of marine species and high rate of endemism, making it one of the world hotspots for marine biodiversity. The basin is also among the most impacted Large Marine Ecosystems in the world due to the combined multiple stressors, such as fishing pressure, habitat loss and degradation, climate change, pollution, eutrophication and the introduction of invasive species. The complexity of Med-LME in its structure/function and dynamics, combined with the socio-political framework of the region make management of its marine resources quite challenging. This contribution aims at highlighting the importance of the Med-LME, with an emphasis on the state of its food web and of its fish/fisheries using modelling tools and national/international reporting. The purpose is to demonstrate the importance of an holistic framework, based on stock assessments and ecosystem based modelling approaches, to be adopted in support of management and conservation measures for the preservation and sustainable use of the Med-LME resources.

RevDate: 2021-01-11

Alghamdi AA (2021)

Impact of the invasive plant species "Nicotiana glauca" toxins on the larvae of the invasive insect species "Rhynchophorus ferrugineus": A damaging pest of date palm trees in Saudi Arabia.

Saudi journal of biological sciences, 28(1):1154-1157.

The wild tree tobacco (Nicotiana glauca) is an alien species that invaded vast areas of the Southwestern region of Saudi Arabia. While, the Red Palm Weevil (RPW) (Rhynchophorus ferrugineus) is considered to be the most damaging invasive insect species of palm trees all over the kingdom of Saudi Arabia, causing major economic losses to farmers and the economy of the country. Using conventional insecticides to control harmful insects such as RPW has undesirable effects on the environment and human health. Alternatively, using biocontrol agents such as poisonous extracts from N. glauca might be a better approach in pest management and can be considered as an eco-friendly, cost-effective, and safe alternative. Therefore, the current study aimed to evaluate the larvicidal effect of N. glauca aqueous extracts against the red palm weevil larvae. The plant specimens were collected from Al-Baha region in the Southwest of Saudi Arabia. Each single test consisted of 20 larvae, and N. glauca preparations were; 1, 1.5, 2, 2.5, and 3 ml, besides the control test. Results obtained for the effect of botanical extracts; leaf, flower, stem and root against R. ferrugineus larvae for an exposure period of 24 hr. at the concentrations of 2.8, 4.2, 6.0, 7.0 and 8.0 ppm. The concentrations for N. glauca extracts reflected an LC50 of 2.7 ppm for leave, 2.6 ppm for flower, 2.8 ppm for stem and 7.00 ppm for root. While, the same concentrations extracts reflected an LC95of 11 ppm for leaf, 9.6 ppm for flower, 8.9 ppm for stem and 13.00 ppm for root. These results showed that N. glauca extracts have a remarkable potentiality as insecticidal substances that can be used as an ecofriendly integrated approach for the management of R. ferrugineus.

RevDate: 2021-01-11

Alharthi AS, Abd-ElGawad AM, AM Assaeed (2021)

Influence of the invasive shrub Nicotiana glauca Graham on the plant seed bank in various locations in Taif region, western of Saudi Arabia.

Saudi journal of biological sciences, 28(1):360-370.

Invasive species have been considered as one of the most serious threats to the biodiversity of various ecosystems, particularly in arid regions. The present study aimed to assess the influence of the invasive shrub Nicotiana glauca on the biodiversity of different habitats in Taif region, Saudi Arabia as well as to determine the highest habitat with seed bank of N. glauca. Soil samples were collected from three locations (Alwaht, Ash-shafa, and Ar Ruddaf), invaded with N. glauca, and analyzed for the soil seed bank. A soil seed experiment was designed in a greenhouse, whereby emerged plant seedlings were left to grow for three months and identified as well as the species density and biodiversity were assessed under and outside the canopy of N. glauca. Also, the floristic composition, life forms, and chorotype spectra of the plant species of the seed bank were analyzed. A total of 42 species, belonging to 23 families, were recorded in the soil seed bank. Asteraceae, Poaceae, and Cyperaceae were the major families (42.9%). The life form spectra of the recorded species were dominated by Therophytes (59.5%). Chorotype spectra analysis revealed that Mediterranean, Saharo-Arabian, and Irano-Turanian were the most represented elements. The species richness and evenness were higher outside the canopy, which indicates a negative effect of the invasive shrub N. glauca on the plant biodiversity in the study area, particularly in Ar Ruddaf location. This could be attributed to the competition or allelopathic effect of N. glauca. In contrast, the density of N. glauca seeds was higher under the canopy compared to outside. The soil nutrients and moisture under the canopy were higher than outside canopy. The present study provides a deeper understanding of the most susceptible habitats or communities to the invasion by N. glauca and thereby open the challenge toward control of this noxious plant and vegetation restoration.

RevDate: 2021-01-11
CmpDate: 2021-01-11

Castillo AI, Chacón-Díaz C, Rodríguez-Murillo N, et al (2020)

Impacts of local population history and ecology on the evolution of a globally dispersed pathogen.

BMC genomics, 21(1):369.

BACKGROUND: Pathogens with a global distribution face diverse biotic and abiotic conditions across populations. Moreover, the ecological and evolutionary history of each population is unique. Xylella fastidiosa is a xylem-dwelling bacterium infecting multiple plant hosts, often with detrimental effects. As a group, X. fastidiosa is divided into distinct subspecies with allopatric historical distributions and patterns of multiple introductions from numerous source populations. The capacity of X. fastidiosa to successfully colonize and cause disease in naïve plant hosts varies among subspecies, and potentially, among populations. Within Central America (i.e. Costa Rica) two X. fastidiosa subspecies coexist: the native subsp. fastidiosa and the introduced subsp. pauca. Using whole genome sequences, the patterns of gene gain/loss, genomic introgression, and genetic diversity were characterized within Costa Rica and contrasted to other X. fastidiosa populations.

RESULTS: Within Costa Rica, accessory and core genome analyses showed a highly malleable genome with numerous intra- and inter-subspecific gain/loss events. Likewise, variable levels of inter-subspecific introgression were found within and between both coexisting subspecies; nonetheless, the direction of donor/recipient subspecies to the recombinant segments varied. Some strains appeared to recombine more frequently than others; however, no group of genes or gene functions were overrepresented within recombinant segments. Finally, the patterns of genetic diversity of subsp. fastidiosa in Costa Rica were consistent with those of other native populations (i.e. subsp. pauca in Brazil).

CONCLUSIONS: Overall, this study shows the importance of characterizing local evolutionary and ecological history in the context of world-wide pathogen distribution.

RevDate: 2021-01-11
CmpDate: 2021-01-11

Laitman JT, KH Albertine (2020)

The Anatomical Record Uncovers Nature's Extreme Species and How They Have Survived in a Novel Two-Volume Special Issue.

Anatomical record (Hoboken, N.J. : 2007), 303(1):7-9.

RevDate: 2021-01-11
CmpDate: 2021-01-11

Smith TD, JT Laitman (2020)

Extreme Anatomy: Gear for the Pioneer.

Anatomical record (Hoboken, N.J. : 2007), 303(1):10-14.

This special issue of The Anatomical Record explores extravagant adaptions that vertebrates have evolved from their base groups to survive in the most challenging environments. The special issue stems from a symposium entitled "Extreme Anatomy: Living beyond the edge," which was held April 23, 2017, at the annual meeting of the American Association of Anatomists, (now called the American Association for Anatomy), in Chicago, IL. In part 1 of this issue, we encounter fossorial mammals and cave-dwelling fish and salamanders that have reduced visual systems accompanied by a variety of mechanosensory adaptations. In rivers and seas, teeth may not suffice in the pursuit of prey: aquatic vertebrates are adorned with armor or weaponry or elaborate keratinous sieves. As vertebrates exploit a great diversity of niches, selection has favored a dizzying array of specialized sensory and locomotor adaptions for deep diving, rapid flight, and navigation through dark and complex settings. Each special adaptation, some seemingly quite "extreme" deviations from an original Bauplan, becomes a tool for a pioneer-like diversification of vertebrates. Anat Rec, 2019. © 2019 American Association for Anatomy.

RevDate: 2021-01-10

Leza M, Herrera C, Picó G, et al (2021)

Six years of controlling the invasive species Vespa velutina in a Mediterranean island: the promising results of an eradication plan.

Pest management science [Epub ahead of print].

BACKGROUND: The yellow-legged hornet, Vespa velutina nigrithorax, is an Invasive Alien Species (IAS) which was accidentally introduced in Europe from Asia. This social insect preys primarily upon honeybees but also upon other pollinators and insects. Consequently, the establishment of this pest has a negative impact on biodiversity, pollination and economy. There is no clear coordination and uniformed methods for eradication measures between countries. Here we present the first field study of the strategy of eradication of the pest species V. velutina that has been conducted in the Westernmost Mediterranean archipelago.

RESULTS: We investigated the combination of different methods like trapping; the use of the citizen science data for detection of presence; the active search of nests; and removal of nests using mechanical methods. The progression of the number of secondary nests found was: 1 (2015), 9 (2016), 20 (2017) and zero during 2018, 2019 and 2020 and just one embryo nest in 2018. More than half of the nests (58%) were detected thanks to citizen science data. The people sent us adult detections, and we started the triangulation method in order to find the nests. The last hornet found in the traps was in June 2018.

CONCLUSION: Early detections of the IAS are crucial to minimise their effects, and citizen science may offer an important source of information to determine the presence and distribution of V. velutina. The findings we present here indicate successful management for this globally significant pest and could contribute to advance the 'science of eradication'. This article is protected by copyright. All rights reserved.

RevDate: 2021-01-10

Blanco A, Larrinaga AR, Neto JM, et al (2021)

Spotting intruders: Species distribution models for managing invasive intertidal macroalgae.

Journal of environmental management, 281:111861 pii:S0301-4797(20)31786-2 [Epub ahead of print].

Invasive macroalgae represent one of the major threats to marine biodiversity, ecosystem functioning and structure, as well as being important drivers of ecosystem services depletion. Many such species have become well established along the west coast of the Iberian Peninsula. However, the lack of information about the distribution of the invaders and the factors determining their occurrence make bioinvasions a difficult issue to manage. Such information is key to enabling the design and implementation of effective management plans. The present study aimed to map the current probability of presence of six invasive macroalgae: Grateloupia turuturu, Asparagopsis armata, Colpomenia peregrina, Sargassum muticum, Undaria pinnatifida, and Codium fragile ssp. fragile. For this purpose, an extensive field survey was carried out along the coast of the north-western Iberian Peninsula. Species distribution models (SDMs) were then used to map the presence probability of these invasive species throughout the study region on the basis of environmental and anthropogenic predictor variables. The southern Galician rias were identified as the main hotspots of macroalgal invasion, with a high probability of occurrence for most of the species considered. Conversely, the probability of presence on the Portuguese coast was generally low. Physico-chemical variables were the most important factors for predicting the distribution of invasive macroalgae contributing between 57.27 and 85.24% to the ensemble models. However, anthropogenic factors (including size of vessels, number of shipping lines, distance from ports, population density, etc.) considerably improved the estimates of the probability of occurrence for most of the target species. This study is one of the few to include anthropogenic factors in SDMs for invasive macroalgae. The findings suggest that management actions aimed at controlling these species should strengthen control and surveillance at ports, particularly in southern Galician rias. Early detection should be of main concern for risk assessment plans on the Portuguese coast.

RevDate: 2021-01-09

Barbosa S (2021)

Is a handful of genes responsible for the common starling invasion success?.

Invasive species have the ability to colonize new habitats across distinct areas of the globe, rapidly adjusting to new biotic and abiotic conditions, and often experiencing little impact from the decrease in effective population size and genetic diversity. Still, as each invading population represents a subsample of the original native distribution, it is common to see variability in terms of the genetic makeup of invading populations and consequently differences in invasion success rates across their non-native range (Blackburn et al. 2017). In a From the Cover article in this issue of Molecular Ecology, Stuart and Cardilini et al. (2020) used Genotyping-by-Sequencing to explore how landscape and environmental heterogeneity shaped the genetic population structure and adaptation of multiple invasions of the common starling in Australia, and compare it to the patterns observed in North America, examined in Hofmeister et al. (2019). Their results suggest that the common starling worldwide invasion has been driven by a handful of genes that allowed adaptation to extreme environmental conditions and might be the key for differences in invasion success.

RevDate: 2021-01-09

Muluvhahothe MM, Joseph GS, Seymour CL, et al (2021)

Repeated surveying over 6 years reveals that fine-scale habitat variables are key to tropical mountain ant assemblage composition and functional diversity.

Scientific reports, 11(1):56.

High-altitude-adapted ectotherms can escape competition from dominant species by tolerating low temperatures at cooler elevations, but climate change is eroding such advantages. Studies evaluating broad-scale impacts of global change for high-altitude organisms often overlook the mitigating role of biotic factors. Yet, at fine spatial-scales, vegetation-associated microclimates provide refuges from climatic extremes. Using one of the largest standardised data sets collected to date, we tested how ant species composition and functional diversity (i.e., the range and value of species traits found within assemblages) respond to large-scale abiotic factors (altitude, aspect), and fine-scale factors (vegetation, soil structure) along an elevational gradient in tropical Africa. Altitude emerged as the principal factor explaining species composition. Analysis of nestedness and turnover components of beta diversity indicated that ant assemblages are specific to each elevation, so species are not filtered out but replaced with new species as elevation increases. Similarity of assemblages over time (assessed using beta decay) did not change significantly at low and mid elevations but declined at the highest elevations. Assemblages also differed between northern and southern mountain aspects, although at highest elevations, composition was restricted to a set of species found on both aspects. Functional diversity was not explained by large scale variables like elevation, but by factors associated with elevation that operate at fine scales (i.e., temperature and habitat structure). Our findings highlight the significance of fine-scale variables in predicting organisms' responses to changing temperature, offering management possibilities that might dilute climate change impacts, and caution when predicting assemblage responses using climate models, alone.

RevDate: 2021-01-09

Cucco M, Alessandria G, Bissacco M, et al (2021)

The spreading of the invasive sacred ibis in Italy.

Scientific reports, 11(1):86.

The spreading of invasive species in new continents can vary from slow and limited diffusion to fast colonisations over vast new areas. We studied the sacred ibis Threskiornis aethiopicus along a 31-year period, from 1989 to 2019, with particular attention to the first area of release in NW Italy. We collected data on species distribution through observations by citizen science projects, population density by transects with distance method, breeding censuses at colonies, and post breeding censuses at roosts. The birds counted at winter roosts in NW Italy increased from a few tens up to 10,880 individuals in 2019. Sacred ibises started breeding in 1989, with a single nest in north-western Italy. The number of breeders remained very low until 2006, when both overwintering and breeding sacred ibises started to increase exponentially and expand their range throughout northern Italy with isolated breeding cases in central Italy. In 2019, the number of nests had increased to 1249 nests in 31 colonies. In NW Italy, the density of foraging birds averaged 3.9 ind./km2 in winter and 1.5 ind./km2 in the breeding period, with a mean size of the foraging groups of 8.9 and 2.1 birds respectively. Direct field observations and species distribution models (SDM) showed that foraging habitats were mainly rice fields and wetlands. A SDM applied to the whole Italian peninsula plus Sardinia and Sicily showed that the variables best related to the SDM were land class (rice fields and wetlands), altitude, and the temperature seasonality. The areas favourable for species expansion encompass all the plains of Northern Italy, and several areas of Tuscany, Latium, Sardinia, and Apulia.

RevDate: 2021-01-09

Skoczowski A, Odrzywolska-Hasiec M, Oliwa J, et al (2021)

Ecophysiological Variability of Alnus viridis (Chaix) DC. Green Alder Leaves in the Bieszczady Mountains (Poland).

Plants (Basel, Switzerland), 10(1): pii:plants10010096.

Alnus viridis (Chaix) DC., green alder, is a fast-growing shrub that grows expansively in the European mountainside. In Poland, A. viridis naturally occurs only in the Bieszczady Mountains (south-eastern part of the country), above the upper forest border. In this study, we assessed the potential of green alder to expand in post-farming areas in the Bieszczady Mountains. We investigated the effects of topographical, climatic, and edaphic characteristics of four various study sites on the physiological and morphological properties of A. viridis leaves in order to answer the question whether the growth of plants in lower positions improves their physiological condition to such an extent that it increases the species invasiveness. This is the first comprehensive ecophysiological study of this species to be carried out in this part of Europe. The photochemical efficiency of PSII, the chlorophyll content, and leaf 13C and 15N discrimination were analyzed. On the basis of leaf radiation reflection, coefficients such as reflectance indices of anthocyanins, carotenoids, flavonoids (ARI2, CRI1, FRI), photochemical index of reflection (PRI), and the water band index (WBI) were calculated. We observed favorable physiological effects in A. viridis plants growing in locations below the upper forest border compared to plants growing in higher locations. As a result, A. viridis may become an invasive species and disturb the phytocoenotic balance of plant communities of the altitudinal zones in the Polish Western Carpathians.

RevDate: 2021-01-08

Xia Z, MacIsaac HJ, Hecky RE, et al (2020)

Multiple factors regulate filtration by invasive mussels: Implications for whole-lake ecosystems.

The Science of the total environment, 765:144435 pii:S0048-9697(20)37966-3 [Epub ahead of print].

The quagga mussel (Dreissena rostriformis bugensis) is a filter-feeding invasive species that has re-engineered many freshwater ecosystems worldwide. High clearance rates (CRs) and dense populations underpin their ecological impacts. CRs, however, are highly variable, as are environmental factors that regulate them. Despite their widespread distribution in Europe and North America, knowledge of how multiple environmental factors regulate CRs of quagga mussels remains limited. We investigated quagga mussel CRs under varying conditions including water temperature, food availability, habitat depth, flow velocity, and duration of incubation in chambers with both static and flowing water. We found that CR was positively related to water temperature and initial food concentration in static chambers. When coupled with limited food concentration, cold water (7.5 °C), due to a deep-water upwelling event, produced very low CR (~ 10× lower) compared to warmer water (12-24 °C) (0.47 vs. 3.12-5.84 L g-1 DW h-1). Mussels from deeper water (20 m) had CRs that were ~ 3.5× higher than from shallower depths (2-10 m) and CRs were inversely affected by total mussel dry weight. Flow rates from 1 to 22 cm s-1 generated a unimodal pattern of CR with an optimal flow velocity of 6-12 cm s-1 (~ 2× higher than suboptimal CRs). Enhanced flow velocity (22 cm s-1), reflective of storm conditions in shallow waters, significantly increased the closing/reopening activity of mussel valves relative to lower velocities (1-12 cm s-1). Incubation time had a strong negative effect (~ 2-4× reduction) on CRs likely reflecting refiltration in static chambers versus food saturation of mussels in flowing chambers, respectively. Our findings highlight how multiple factors can influence quagga mussel CRs by factors of 2-10. Given widespread habitat heterogeneity in large aquatic ecosystems, whole-lake estimates of mussel impacts should include multiple regulatory factors that affect mussel filtration.

RevDate: 2021-01-08

García-Díaz P, Binny RN, DP Anderson (2021)

How important is individual foraging specialisation in invasive predators for native-prey population viability?.

Oecologia [Epub ahead of print].

Predation by invasive species is a major threat to the persistence of naïve prey. Typically, this negative effect is addressed by suppressing the population size of the invasive predator to a point where the predation pressure does not hinder the viability of the prey. However, this type of intervention may not be effective whenever a few specialised predators are the cause of the decline. We investigated the effects of varying levels of specialised invasive stoats (Mustela erminea) abundance on the long-term viability of simulated kiwi (Apteryx spp.) populations. We explored four scenarios with different proportions of highly specialised stoats, which were those that had a ≥ 0.75 probability of predating kiwi eggs and chicks if they were within their home range: (i) a stoat population composed mostly of generalists (mean: 0.5 probability of predation across the population); (ii) 5% of highly specialised stoats and the remaining being generalists; (iii) 10% of highly specialised stoats and the remaining being generalists; and, (iv) half highly specialised stoats and half generalists. We found that stoat home range sizes, rather than stoat density or the density of highly specialised stoats, was the main driver of kiwi population trends. Stoats with large home ranges were more likely to predate kiwi eggs and chicks as these were more likely to fall within a large home range. More broadly, our findings show how the daily individual ranging and foraging behaviour of an invasive predator can scale-up to shape population trends of naïve prey.

RevDate: 2021-01-08

David OA, Akomolafe GF, Akanmu AO, et al (2021)

The impact of tantalite mining on the flora diversity in Nasarawa state, Nigeria.

Environmental monitoring and assessment, 193(1):46.

The activities of the artisanals and small-scale miners in Nasarawa state, Nigeria, are increasing daily without considering the loss of biodiversity, which has continuously disrupted ecological functions and environmental balance. The study aimed at investigating the effect of tantalite mining activities on flora diversity. Three study sites were selected for floristic data collection, comprising tantalite mining site A situated in Azara, Awe LGA; tantalite mining site B situated in Tunga, Awe LGA; and referred site C situated along the Makurdi-Obi Road, Lafia LGA. Eight plots of 20 × 20 m were systematically placed along two transect lines of 1000 m with 500 m distance apart. The total numbers of 32 plant species, at the ratio of 11:20:21 individual species, were found in sites A, B, and referred site C, respectively. Tantalite mining site A showed 46% rare herbs dominating the site, with an introduction of new non-native species of Jateorhiza spp. and Hyptis suaveolens, presenting a significantly high number of individuals (p ˂ 0.0069). Tantalite site B, Tunga, had 50% reductions of several indigenous tree species such as Daniellia oliveri and Vitex doniana, while site A had 75% reduction of tree species. Therefore, the floristic diversity in site A endured a higher degradation than in site B. The indigenous species in site A were almost completely replaced with problematic weeds, invasive weed species, and non-native plant species. The tree diversities in sites A and B were seriously threatened, and H. suaveolens has been regarded as a potentially invasive plant species in Nasarawa state, Nigeria.

RevDate: 2021-01-08

James SW, Csuzdi C, Chang CH, et al (2021)

Comment on "Global distribution of earthworm diversity".

Science (New York, N.Y.), 371(6525):.

Phillips et al (Reports, 25 October 2019, p. 480) incorrectly conclude that tropical earthworm communities are less diverse and abundant than temperate communities. This result is an artifact generated by some low-quality datasets, lower sampling intensity in the tropics, different patterns in richness-area relationships, the occurrence of invasive species in managed soils, and a focus on local rather than regional richness.

RevDate: 2021-01-08

Altuna M, Hickner PV, Castro G, et al (2021)

New World screwworm (Cochliomyia hominivorax) myiasis in feral swine of Uruguay: One Health and transboundary disease implications.

Parasites & vectors, 14(1):26.

BACKGROUND: Feral swine (Sus scrofa) are highly invasive and threaten animal and human health in the Americas. The screwworm (Cochliomyia hominivorax) is listed by the World Organization for Animal Health as a notifiable infestation because myiasis cases affect livestock, wildlife, and humans in endemic areas, and outbreaks can have major socioeconomic consequences in regions where the screwworm has been eradicated. However, a knowledge gap exists on screwworm infestation of feral swine in South America, where the screwworm is endemic. Here, we report screwworm infestation of feral swine harvested in Artigas Department (Uruguay), where the Republic of Uruguay shares borders with Brazil and Argentina.

METHODS: Myiasis caused by the larvae of screwworm were identified in feral swine with the support and collaboration of members of a local feral swine hunting club over a 3-year period in the Department of Artigas. Harvested feral swine were examined for the presence of lesions where maggots causing the myiasis could be sampled and processed for taxonomic identification. The sites of myiasis on the body of infested feral swine and geospatial data for each case were recorded. The sex and relative size of each feral swine were also recorded. Temperature and precipitation profiles for the region were obtained from public sources.

RESULTS: Myiases caused by screwworms were recorded in 27 of 618 the feral swine harvested. Cases detected in males weighing > 40 kg were associated with wounds that, due to their location, were likely caused by aggressive dominance behavior between adult males. The overall prevalence of screwworm infestation in the harvested feral swine was associated with ambient temperature, but not precipitation. Case numbers peaked in the warmer spring and summer months.

CONCLUSIONS: This is the first report on myiasis in feral swine caused by screwworm in South America. In contrast to myiasis in cattle, which can reach deep into host tissues, screwworms in feral swine tended to cause superficial infestation. The presence of feral swine in screwworm endemic areas represents a challenge to screwworm management in those areas. Screwworm populations maintained by feral swine may contribute to human cases in rural areas of Uruguay, which highlights the importance of the One Health approach to the study of this invasive host species-ectoparasite interaction.

RevDate: 2021-01-07

Bolds SA, Lockaby BG, Ditchkoff SS, et al (2021)

Impacts of a large invasive mammal on water quality in riparian ecosystems.

Journal of environmental quality [Epub ahead of print].

Wild pigs (Sus scrofa) are a highly invasive species in many regions of the world and can act as ecosystem engineers in areas where they are established. In riparian ecosystems, wild pigs may impact water quality parameters and introduce fecal bacteria, although previous studies have reported conflicting results. We propose four conditions that we believe are needed for an accurate assessment of wild pig impacts on water quality and address each one in our study. Water samples were collected between May 2018 and June 2019 in riparian watersheds on a privately-owned property in Alabama that was densely populated by wild pigs (treatment) and in watersheds at a nearby national forest without an established population. Samples were analyzed for concentrations of water quality parameters such as anions and cations, dissolved oxygen, total suspended solids, nitrogen, dissolved organic carbon, and Escherichia coli and other fecal coliforms. An additional 38 samples were analyzed using quantitative PCR for swine fecal bacteroidetes. At treatment watersheds, specific conductivity, concentrations of organic N and C, SO42- , and Ca2+ were between 2 to 11 times that of reference watersheds. E. coli values at treatment watersheds were 40 times reference watershed values. DNA from swine fecal bacteroidetes was detected in 70% of treatment samples and 0% of reference samples. Wild pigs are a threat to water quality in riparian areas and our results indicate that it may be important to control populations upstream of major drinking water sources and recreational areas. This article is protected by copyright. All rights reserved.

RevDate: 2021-01-06

Kemp L, Aldridge DC, Booy O, et al (2021)

80 questions for UK biological security.

PloS one, 16(1):e0241190 pii:PONE-D-19-34679.

Multiple national and international trends and drivers are radically changing what biological security means for the United Kingdom (UK). New technologies present novel opportunities and challenges, and globalisation has created new pathways and increased the speed, volume and routes by which organisms can spread. The UK Biological Security Strategy (2018) acknowledges the importance of research on biological security in the UK. Given the breadth of potential research, a targeted agenda identifying the questions most critical to effective and coordinated progress in different disciplines of biological security is required. We used expert elicitation to generate 80 policy-relevant research questions considered by participants to have the greatest impact on UK biological security. Drawing on a collaboratively-developed set of 450 questions, proposed by 41 experts from academia, industry and the UK government (consulting 168 additional experts) we subdivided the final 80 questions into six categories: bioengineering; communication and behaviour; disease threats (including pandemics); governance and policy; invasive alien species; and securing biological materials and securing against misuse. Initially, the questions were ranked through a voting process and then reduced and refined to 80 during a one-day workshop with 35 participants from a variety of disciplines. Consistently emerging themes included: the nature of current and potential biological security threats, the efficacy of existing management actions, and the most appropriate future options. The resulting questions offer a research agenda for biological security in the UK that can assist the targeting of research resources and inform the implementation of the UK Biological Security Strategy. These questions include research that could aid with the mitigation of Covid-19, and preparation for the next pandemic. We hope that our structured and rigorous approach to creating a biological security research agenda will be replicated in other countries and regions. The world, not just the UK, is in need of a thoughtful approach to directing biological security research to tackle the emerging issues.

RevDate: 2021-01-06

Salata S, BL Fisher (2021)

Taxonomic revision of Madagascan species of the Pheidole fervens species-group (Hymenoptera, Formicidae).

PloS one, 16(1):e0244195 pii:PONE-D-20-27899.

Madagascar, one of the top megadiversity regions, hosts one of the highest numbers of endemic and threatened organisms on earth. One of the most spectacular examples of ant radiation on the island has occurred in the hyperdiverse genus Pheidole. To this date, there are 117 described Madagascan Pheidole divided into 16 species-groups, and 97% of them are endemic to the island. Only two of these species-groups contain widely distributed invasive species in addition to native, endemic taxa: megacephala, and fervens species-groups. Here we revise the fervens species-group and discuss updated distribution records of its introduced members on Madagascar. We recognize six species belonging to this group, including five new to science: Pheidole ampangabe sp. nov., P. arivo sp. nov., P. comosa sp. nov., P. indica Mayr, P. mamirapiratra sp. nov., and P. mena sp. nov. Detailed descriptions are supplemented with measurements, diagnoses, identification key, high-resolution images for major and minor worker, and comments on distribution and biology.

RevDate: 2021-01-06

Champer J, Kim IK, Champer SE, et al (2021)

Suppression gene drive in continuous space can result in unstable persistence of both drive and wild-type alleles.

Molecular ecology [Epub ahead of print].

Rapid evolutionary processes can produce drastically different outcomes when studied in panmictic population models versus spatial models. One such process is gene drive, which describes the spread of "selfish" genetic elements through a population. Engineered gene drives are being considered for the suppression of disease vectors or invasive species. While laboratory experiments and modeling in panmictic populations have shown that such drives can rapidly eliminate a population, it remains unclear if these results translate to natural environments where individuals inhabit a continuous landscape. Using spatially explicit simulations, we show that the release of a suppression drive can result in what we term "chasing" dynamics, in which wild-type individuals recolonize areas where the drive locally eliminated the population. Despite the drive subsequently reconquering these areas, complete population suppression often fails to occur or is substantially delayed. This increases the likelihood that the drive is lost or that resistance evolves. We analyze how chasing dynamics are influenced by the type of drive, its efficiency, fitness costs, and ecological factors such as the maximal growth rate of the population and levels of dispersal and inbreeding. We find that chasing is more common for lower efficiency drives when dispersal is low and that some drive mechanisms are substantially more prone to chasing behavior than others. Our results demonstrate that the population dynamics of suppression gene drives are determined by a complex interplay of genetic and ecological factors, highlighting the need for realistic spatial modeling to predict the outcome of drive releases in natural populations.

RevDate: 2021-01-06

Savadova-Ratkus K, Mazur-Marzec H, Karosienė J, et al (2021)

Interplay of Nutrients, Temperature, and Competition of Native and Alien Cyanobacteria Species Growth and Cyanotoxin Production in Temperate Lakes.

Toxins, 13(1): pii:toxins13010023.

Global warming and eutrophication contribute to formation of HABs and distribution of alien cyanobacteria northward. The current study assessed how alien to Europe Sphaerospermopsis aphanizomenoides and Chrysosporum bergii will co-occur with dominant native Planktothrix agardhii and Aphanizomenon gracile species under changing conditions in temperate freshwaters. The experiments were carried out to examine the effect of nutrients and temperature on the growth rate of cyanobacteria, production of cyanotoxins, and interspecies competition. The highest growth rate was determined for A. gracile (0.43 day-1) and S. aphanizomenoides (0.40 day-1) strains at all the tested nutrient concentrations (IP and IN were significant factors). S. aphanizomenoides adapted to the wide range of nutrient concentrations and temperature due to high species ecological plasticity; however, A. gracile was able to suppress its dominance under changing conditions. Regularity between tested variables and STX concentration in A. gracile was not found, but IP concentration negatively correlated with the amount of dmMC-RR and other non-ribosomal peptides (NRPs) in P. agardhii strains. The relative concentration of NRPs in nontoxic P. agardhii strain was up to 3-fold higher than in MC-producing strain. Our study indicated that nutrients, temperature, and species had significant effects on interspecies competition. A. gracile had a negative effect on biomass of both alien species and P. agardhii.

RevDate: 2021-01-06
CmpDate: 2021-01-06

Zhang J, Huang W, J Ding (2021)

Phenotypic plasticity in resource allocation to sexual trait of alligatorweed in wetland and terrestrial habitats.

The Science of the total environment, 757:143819.

Environmental heterogeneity in resource availability affects invasive plant reproductive strategies and resource allocation to reproduction. Here, we conducted two field surveys to examine the effect of wetland and terrestrial habitats on inflorescence production and resource allocation to inflorescence of the amphibious invasive plant Alternanthera philoxeroides in its invasive range (China). We also specifically examined the effects of water availability, fertilizer application, and plant density (space) in a greenhouse experiment. In field surveys, inflorescence biomass, normal monoclinous flowers and ratio of inflorescences to shoots of plants from wetlands were about 2.4-, 0.8- and 1.3-fold higher than those from terrestrial habitats, respectively. In greenhouse experiment, plants with higher fertilizer application and lower competition conditions produced more inflorescences, and had a lower ratio of roots to shoots and a comparable ratio of inflorescences to shoot and root. Furthermore, water availability had a significant interactive effect when combined with fertilizer level or plant density on inflorescence production and resource allocation. Together, our results indicate that high resources, such as those found in wetland habitats, favor both vegetative growth and sexual trait in A. philoxeroides. However, in terrestrial habitats where resources are relatively poor, the invader can adapt to the environment by allocating more resources to vegetative growth for clonal reproduction and less resources for sexual trait. This phenotypic plasticity in resource allocation likely facilitates the plant to invade heterogeneous wetlands and terrestrial environments.

RevDate: 2021-01-06
CmpDate: 2021-01-06

Lantschner MV, Corley JC, AM Liebhold (2020)

Drivers of global Scolytinae invasion patterns.

Ecological applications : a publication of the Ecological Society of America, 30(5):e02103.

Biological invasions are affected by characteristics of invading species, strength of pathway connectivity among world regions and habitat characteristics of invaded regions. These factors may interact in complex ways to drive geographical variation in numbers of invasions among world regions. Understanding the role of these drivers provides information that is crucial to the development of effective biosecurity policies. Here we assemble for the first time a global database of historical invasions of Scolytinae species and explore factors explaining geographical variation in numbers of species invading different regions. This insect group includes several pest species with massive economic and ecological impacts and these beetles are known to be accidentally moved with wood packaging in global trade. Candidate explanatory characteristics included in this analysis are cumulative trade among world regions, size of source species pools, forest area, and climatic similarity of the invaded region with source regions. Species capable of sib-mating comprised the highest proportion on nonnative Scolytines, and these species colonized a higher number of regions than outbreeders. The size of source species pools offered little power in explaining variation in numbers of invasions among world regions nor did climate or forest area. In contrast, cumulative trade had a strong and consistent positive relationship with numbers of Scolytinae species moving from one region to another, and this effect was highest for bark beetles, followed by ambrosia beetles, and was low for seed and twig feeders. We conclude that global variation in Scolytine invasions is primarily driven by variation in trade levels among world regions. Results stress the importance of global trade as the primary driver of historical Scolytinae invasions and we anticipate other hitchhiking species would exhibit similar patterns. One implication of these results is that invasions between certain world regions may be historically low because of past low levels of trade but future economic shifts could result in large numbers of new invasions as a result of increased trade among previously isolated portions of the world. With changing global flow of goods among world regions, it is crucial that biosecurity efforts keep pace to minimize future invasions and their impacts.

RevDate: 2021-01-06
CmpDate: 2021-01-06

Forcina G, Guerrini M, F Barbanera (2020)

Non-native and hybrid in a changing environment: conservation perspectives for the last Italian red-legged partridge (Alectoris rufa) population with long natural history.

Zoology (Jena, Germany), 138:125740.

The ever-increasing biotic homogenization - especially when associated with introgressive hybridization - raises concern for the reduction of the spatial component of diversity in wildlife worldwide. Nonetheless, there is a growing attention to the potential conservation value of hybridization in fastening the adaptive evolutionary responses to rapidly changing selective pressures. Under these premises, we investigated the genetic affinity of the red-legged partridge (Alectoris rufa) population inhabiting Elba Island (Italy) in the context of the overall species phylogeography and particularly of the nominate subspecies it is traditionally ascribed to. Although notoriously hybrid with the congeneric A. chukar, this island population is of undisputedly value because of its long natural history and self-sustainability. As such, its adaptive conservation management calls for a comprehensive knowledge including the assessment of its geographic origin. For this purpose, 110 fecal samples were collected across Elba, genotyped at their joint Cytochrome-b and Control Region genes (2,249 characters), and compared with 149 conspecifics from all over the species distribution range. We confirmed a widespread A. chukar mitochondrial DNA introgression in Elba partridges, whereas their expected formal assignment to the nominate subspecies from Italy and France was rejected, since these turned out to be closely related to conspecifics from the Iberian Peninsula. This counterintuitive result found support in a large variety of literary sources and compelling evidences from personal testimonies revealing recent intense management with farm-reared birds of Spanish origin. Although the nativeness of Elba partridges was disproved, we advise local authorities to keep warranting the ongoing conservation efforts - and especially restore the connectivity between the western and eastern island sub-populations - as this resource may still be conceived as the ultimate repository for part of the otherwise extinct Italian A. r. rufa genome. Indeed, the admixture with conspecifics from the Iberian Peninsula does not necessarily mean that the entirety of the native nuclear genome of Elba partridges has been wiped out. Furthermore, these latter represent an interesting case study in conservation biology to investigate the possible role played by introgressive hybridization in the adaptation to recent land use and vegetation cover changes associated with rural abandonment in an insular yet heavily anthropized context.

RevDate: 2021-01-06
CmpDate: 2021-01-06

Cui Y, Ren YD, Lyu M, et al (2020)

Genomic divergences between the two polyphagous Spodoptera relatives provide cues for successful invasion of the fall armyworm.

Insect science, 27(6):1257-1265.

The fall armyworm Spodoptera frugiperda recently invaded China, ravaging crops in many provinces. Deciphering the possible genetic basics for its successful invasion is critical for innovative and specific control for this gluttonous pest. Here we generated comparative genomic analyses between S. frugiperda and its native relative, S. litura, which differs in host preference, locomotivity and production behavior. We demonstrated that S. frugiperda genes are enriched in taste sensory perception and nervous system, obviously different from those of S. litura. Potential host adaptation genes showed generally an elevated ratio of non-synonymous substitution rate to synonymous substitution rate, suggesting a faster evolution during the divergence of the two species. Focusing on these sets of genes, we identified 23 genes being under positive selection in S. frugiperda. Among them are two notable genes involved in sensory perception, gustatory receptor (GR) and an acetaldehyde oxidase, which are important for host detection in invasion and expansion processes. Another two genes are mitochondrial adenosine triphosphate synthase β subunit and ferritin heavy chain, which may be associated with the enhanced locomotivity and resistance, which fascinated long-distance migration needed for invasion and rapid expansion. Another interesting gene is chorion protein, in which positive selection sites in S. frugiperda were found and a replacement in one site is predicted to affect the protein function, which might be associated with competent reproductivity in S. frugiperda to ensure genetic resources for expansion.

RevDate: 2021-01-06
CmpDate: 2021-01-06

Liu ZD, Mi GB, Raffa KF, et al (2020)

Physical contact, volatiles, and acoustic signals contribute to monogamy in an invasive aggregating bark beetle.

Insect science, 27(6):1285-1297.

The behavioral strategies and mechanisms by which some insects maintain monogamous mating systems are not well understood. We investigated the mating system of the bark beetle Dendroctonus valens, and identified several contributing mechanisms. Field and laboratory observations suggest the adults commonly form permanent bonds during host colonization. Moreover, it showed mated females that remained paired with males produced more offspring than mated females that were alone in galleries. In bioassays, a second female commonly entered a gallery constructed by a prior female. Videos show she commonly reached the location of the first female, but they did not engage in actual fighting. Rather, the second female typically departs to form her own gallery. Acoustic signaling likewise does not appear to influence female-female encounters, based on controlled muting experiments. Instead, the intruder appears to perceive the resident's presence by physical contact. Both acoustic signals and volatiles released by females during gallery constructing were shown to attract males. After a male joined a female in a gallery, the male-produced aggressive sounds, which were shown by playback to deter other males from entering the gallery. Unlike female-female interactions, resident males use their head and rear to push intruders out of galleries. Additionally, volatiles released by males during feeding repelled intruding males, discouraging them from entering the gallery. Males also construct plugs that block the entrance, which may prevent subsequent males and predators from entering the gallery. Thus, D. valens has evolved multifaceted mechanisms contributing to single pairings that confer benefits to both sexes.

RevDate: 2021-01-04

Castaño-Quintero S, Escobar-Luján J, Osorio-Olvera L, et al (2020)

Supraspecific units in correlative niche modeling improves the prediction of geographic potential of biological invasions.

PeerJ, 8:e10454 pii:10454.

Background: Biological invasions rank among the most significant threats to biodiversity and ecosystems. Correlative ecological niche modeling is among the most frequently used tools with which to estimate potential distributions of invasive species. However, when areas accessible to the species across its native distribution do not represent the full spectrum of environmental conditions that the species can tolerate, correlative studies often underestimate fundamental niches.

Methods: Here, we explore the utility of supraspecific modeling units to improve the predictive ability of models focused on biological invasions. Taking into account phylogenetic relationships in correlative ecological niche models, we studied the invasion patterns of three species (Aedes aegypti, Pterois volitans and Oreochromis mossambicus).

Results: Use of supraspecific modeling units improved the predictive ability of correlative niche models in anticipating potential distributions of three invasive species. We demonstrated that integrating data on closely related species allowed a more complete characterization of fundamental niches. This approach could be used to model species with invasive potential but that have not yet invaded new regions.

RevDate: 2021-01-04

Hedrick PW (2020)

Heterozygosity levels and estimation of self-fertilization in an invasive species.

Ecology and evolution, 10(24):14451-14452 pii:ECE36885.

RevDate: 2021-01-04

Wang B, Li K, ZQ He (2020)

The genetic differentiation of a cricket (Velarifictorus micado) with two modes of life cycle in East Asia after the middle Pleistocene and the invasion origin of the United States of America.

Ecology and evolution, 10(24):13767-13786 pii:ECE36967.

The cricket Velarifictorus micado is widely distributed in East Asia and colonized the United States of America (the USA) in 1959. It has two life cycles: egg and nymph diapause. We aimed to investigate the biogeographic boundary between them and determine when and why V. micado diverged. Mitochondrial fragments including COI and CytB were used for haplotype network, demographic analysis, and divergence time estimation in individuals of East Asia. We selected several samples from the USA to find out the colonization origin. The haplotype network indicated there were three lineages based on COI, NE lineage (the egg diapause and mainly distributed in the northern regions), SE lineage (the egg diapause and mainly distributed in the southern regions), and SN lineage (the nymph diapause and mainly distributed in the southern regions). The molecular chronograms indicated that the first divergence of V. micado into two main lineages, NE and southern lineages (SE and SN), was essentially bounded by the Yangtze River. It occurred around ~0.79 Ma (95% HPD: 1.13-0.46 Ma) in the Middle Pleistocene Transition. This was followed by the divergence of the southern lineage into two sublineages, SE and SN lineage, occurred around ~0.50 Ma (95% HPD: 0.71-0.25 Ma), corresponding to the time of development of glaciers in various parts of the Qinghai-Tibet Plateau (QTP) (0.73-0.46 Ma). SE lineage might originate from southwestern China based on the comparison between the haplotype network based on COI and CytB. Our study suggested that divergences of lineages have twice co-occurred with tendency of cooling climatic in Asia after the Mid-Pleistocene, and the life-history strategy may play an important role in lineage diversification. Additionally, our results indicated that the USA populations were revealed at least twice separate Asian invasions. These both belonged to the egg diapause, which might provide a new perspective for invasion control.

RevDate: 2021-01-04

Ramula S, A Kalske (2020)

Introduced plants of Lupinus polyphyllus are larger but flower less frequently than conspecifics from the native range: Results of the first year.

Ecology and evolution, 10(24):13742-13751 pii:ECE36964.

Introduced species, which establish in novel environments, provide an opportunity to explore trait evolution and how it may contribute to the distribution and spread of species. Here, we explore trait changes of the perennial herb Lupinus polyphyllus based on 11 native populations in the western USA and 17 introduced populations in Finland. More specifically, we investigated whether introduced populations outperformed native populations in traits measured in situ (seed mass) and under common garden conditions during their first year (plant size, flowering probability, and number of flowering shoots). We also explored whether climate of origin (temperature) influenced plant traits and quantified the degree to which trait variability was explained collectively by country and temperature as compared to other population-level differences. Three out of four plant traits differed between the native and introduced populations; only seed mass was similar between countries, with most of its variation attributed to other sources of intraspecific variation not accounted for by country and temperature. Under common garden conditions, plants originating from introduced populations were larger than those originating from native populations. However, plants from the introduced range flowered less frequently and had fewer flowering shoots than their native-range counterparts. Temperature of a population's origin influenced plant size in the common garden, with plant size increasing with increasing mean annual temperature in both native and introduced populations. Our results of the first year reveal genetic basis for phenotypic differences in some fitness-related traits between the native and introduced populations of L. polyphyllus. However, not all of these trait differences necessarily contribute to the invasion success of the species and thus may not be adaptive, which raises a question how persistent the trait differences observed in the first year are later in individuals' life for perennial herbs.

RevDate: 2021-01-04

Parker ES, AP Moczek (2020)

Don't stand so close to me: Microbiota-facilitated enemy release dynamics in introduced Onthophagus taurus dung beetles.

Ecology and evolution, 10(24):13640-13648 pii:ECE36836.

Microbial symbionts can influence their hosts in stunningly diverse ways. Emerging research suggests that an underappreciated facet of these relationships is the influence microbes can have on their host's responses to novel, or stressful, environmental conditions. We sought to address these and related questions in populations resulting from the recent introduction and subsequent rapid range expansion of Onthophagus taurus dung beetles. Specifically, we manipulated both microbial communities and rearing temperature to detect signatures of developmental and life history differentiation in response to the local thermal conditions in two populations derived from the southern most (Florida) and northern most (Michigan) extremes of the exotic Eastern U.S. range of O. taurus. We then sought to determine the contributions, if any, of host-associated microbiota to this differentiation. We found that when reared under common garden conditions individuals from Florida and Michigan populations differed significantly in developmental performance measures and life history traits, consistent with population divergence. At the same time, and contrary to our predictions, we failed to find support for the hypothesis that animals perform better if reared at temperatures that match their location of origin and that performance differences may be mediated by host-associated microbiota. Instead, we found that microbiome swapping across host populations improved developmental performance in both populations, consistent with enemy release dynamics. We discuss the implications of our results for our understanding of the rapid spread of exotic O. taurus through the Eastern United States and the significance of symbiosis in host responses to novel environmental conditions more broadly.

RevDate: 2021-01-04

Putman BJ, Pauly GB, DT Blumstein (2020)

Urban invaders are not bold risk-takers: a study of 3 invasive lizards in Southern California.

Current zoology, 66(6):657-665.

Biological invasions threaten biodiversity worldwide, and therefore, understanding the traits of successful invaders could mitigate their spread. Many commonly invasive species do well in disturbed habitats, such as urban environments, and their abilities to effectively respond to disturbances could contribute to their invasiveness. Yet, there are noninvasive species that also do well in disturbed habitats. The question remains whether urban invaders behave differently in urban environments than noninvaders, which could suggest an "urban-exploiting" phenotype. In Southern California, the co-occurrence of invasive Italian wall lizards Podarcis siculus, brown anoles Anolis sagrei, and green anoles A. carolinensis, and native western fence lizards Sceloporus occidentalis offers an opportunity to test whether invasives exhibit consistent differences in risk-taking within human-altered habitats compared with a native species. We predicted that invasive lizards would exhibit more bold behavior by having shorter flight-initiation distances (FIDs) and by being found farther from a refuge (behaviors that would presumably maximize foraging in low-risk environments). Invasive populations had similar or longer FIDs, but were consistently found at distances closer to a refuge. Collectively, invasive lizards in urban habitats were not bolder than a native species. Reliance on nearby refuges might help species successfully invade urban habitats, and if a general pattern, may pose an added challenge in detecting or eliminating them.

RevDate: 2021-01-04

Camacho MJ, de Andrade E, Mota M, et al (2020)

Potato Cyst Nematodes: Geographical Distribution, Phylogenetic Relationships and Integrated Pest Management Outcomes in Portugal.

Frontiers in plant science, 11:606178.

The identification and phylogenetic relationships of potato cyst nematodes (PCN) were studied to assess the potential value of geographical distribution information for integrated pest management of potato production in Portugal. This research focused on PCN species, Globodera pallida and Globodera rostochiensis. From 2013 until 2019, 748 soil samples from the rhizosphere of different potato cultivars were surveyed in the Portuguese mainland to detect and identify both species and track their location. PCN are widespread invasive species throughout Portugal. In fact, during the survey period an incidence of 22.5% was estimated for the tested samples. The patterns of infestation vary among regions, increasing from south to north, where PCN were first detected. Currently, both species are present in all potato producing regions of the country, with a greater incidence of G. pallida. Phytosanitary control measures are influencing to the observed results. The use of potato cultivars resistant to G. rostochiensis led to a decrease of this species but had no influence on G. pallida detections, which continues its reproduction freely since there are no effective resistant cultivars for this species. The relationship between the presence, infestation rate, spread and geographical distribution of PCN is discussed in terms of behavioral responses of the potato cultivars and the implications for developing new integrated crop protection measures.


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.

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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

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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

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Curriculum Vitae for R J Robbins

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