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Abstract
Pesticide use is well known to be detrimental for maintaining biodiversity in the agricultural landscape. Amphibians are especially affected by these agrochemicals. In particular, these animals' high sensitivity was demonstrated for glyphosate-based herbicides which are dominating the world market today. Pesticide impacts are influenced by several co-stressors, and we for the first time link the exposure risk of amphibians to these commonly used pesticides to observed recent effects from ongoing climate change. In a simple verbal model, based on present-day data from Germany, we show that amphibian populations which have undergone phenological shift towards earlier reproduction potentially suffer less from applications of glyphosate-based herbicides compared to those which (yet) show no such reproductive shift. Although, apparently observed recent climate change effects lower the exposure risk, we advocate that amphibians are not necessarily safer now, mainly because farmers most likely will adapt their cultivation practices in the future if climate change becomes more obvious. Rather, we conclude that combining pesticide applications, climate change and phenological responses need an increased consideration in amphibian conservation. The results from our verbal model should be seen as a hypothesis that needs to be tested with specific field studies and (based on these data which are widely lacking today) more complex modelling of future exposure risk of pesticides to amphibians.

Globalization has facilitated the emergence and spread of novel pathogens, representing a major conservation challenge. The amphibian disease chytridiomycosis, caused by the fungal pathogen Batrachochytrium dendrobatidis, epitomizes this unprecedented threat, being responsible for declines and extinctions of amphibians worldwide. Chytridiomycosis has had both immediate catastrophic impacts during initial epidemics, as well as more variable, ongoing effects as the pathogen transitions to endemicity in its new distribution. Where B. dendrobatidis is now endemic, effective management actions are needed to prevent further extinctions of species. Yet, after nearly 20 years of research, management solutions remain rare or largely untested. Here, we highlight the potential for mitigation strategies focused on the environmental part of the host-pathogen-environment triangle to facilitate coexistence with the pathogen, using an extensive literature review to demonstrate that environmental conditions and demographic processes can strongly mediate the impact of B. dendrobatidis, and the capacity of amphibian populations to withstand disease-associated mortality. In particular, novel management approaches to achieve coexistence could focus on manipulating environmental conditions to decrease suitability for B. dendrobatidis and/or increase demographic resilience to disease-associated mortality. Such strategies include translocation to, or creation of, environmental refuges, and habitat manipulation to increase recruitment and offset elevated adult mortality. We argue that responding to chytridiomycosis requires a conceptual readjustment of our baselines to recognize that endemic B. dendrobatidis infection is the 'new normal' in surviving populations of many susceptible amphibian species. We conclude with recommendations for research and management actions that can help achieve coexistence of amphibian species susceptible to B. dendrobatidis. ; Australian Government's National Environmental Science Program Threatened Species Recovery Hub

We present a conservation genetics tool kit, which offers two ready-to-use workflows for the routine application of genetic methods in conservation management. The workflows were optimized for work load and costs and are accompanied by an easy-to-read and richly illustrated manual with guidelines regarding sampling design, sampling of genetic material, necessary permits, laboratory methods, statistical analyses and documentation of results in a practice-oriented way. The manual also provides a detailed interpretation help for the implementation of the results in conservation management. One workflow deals with the identification of pond-breeding amphibians based on metabarcoding and environmental DNA (eDNA) from water samples. This workflow also discriminates the morphologically similar water frogs (Pelophylax sp.) and other closely related species (e.g. Triturus cristatus and T. carnifex). The second workflow studies connectivity among populations using microsatellite markers. Its statistical analyses encompass the detection of genetic groups and historical, recent and current dispersal and gene flow. Using the two workflows does not involve academic research institutes; they can be applied by environmental consultancies, laboratories from the private sector, governmental agencies or non-governmental organisations. These and additional conservation genetic workflows will hopefully foster the routine use of genetic methods in conservation management. ; ISSN:1877-7252 ; ISSN:1877-7260

Protected areas (PAs) play a critical role in conserving biodiversity and maintaining viable populations of threatened species. Yet, as global change could reduce the future effectiveness of existing PAs in covering high species richness, updating the boundaries of existing PAs or creating new ones might become necessary to uphold conservation goals. Modelling tools are increasingly used by policymakers to support the spatial prioritization of biodiversity conservation, enabling the inclusion of scenarios of environmental changes to achieve specific targets. Here, using the Western Swiss Alps as a case study, we show how integrating species richness derived from species distribution model predictions for four taxonomic groups under present and future climate and land-use conditions into two conservation prioritization schemes can help optimize extant and future PAs. The first scheme, the "Priority Scores Method" identified priority areas for the expansion of the existing PA network. The second scheme, using the zonation software, allowed identifying priority conservation areas while incorporating global change scenarios and political costs. We found that existing mountain PAs are currently not situated in the most environmentally nor politically suitable locations when maximizing alpha diversity for the studied taxonomic groups and that current PAs could become even less optimum under the future climate and land-use change scenarios. This analysis has focused on general areas of high species richness or species of conservation concern and did not account for special habitats or functional groups that could have been used to create the existing network. We conclude that such an integrated framework could support more effective conservation planning and could be similarly applied to other landscapes or other biodiversity conservation indices.

Since amphibian declines were first proposed as a global phenomenon over a quarter century ago, the conservation community has made little progress in halting or reversing these trends. The early search for a "smoking gun" was replaced with the expectation that declines are caused by multiple drivers. While field observations and experiments have identified factors leading to increased local extinction risk, evidence for effects of these drivers is lacking at large spatial scales. Here, we use observations of 389 time-series of 83 species and complexes from 61 study areas across North America to test the effects of 4 of the major hypothesized drivers of declines. While we find that local amphibian populations are being lost from metapopulations at an average rate of 3.79% per year, these declines are not related to any particular threat at the continental scale; likewise the effect of each stressor is variable at regional scales. This result - that exposure to threats varies spatially, and populations vary in their response - provides little generality in the development of conservation strategies. Greater emphasis on local solutions to this globally shared phenomenon is needed. ; US Geological Survey ; This work was conducted as part of the Amphibian Decline Working Group supported by the John Wesley Powell Center for Analysis and Synthesis, funded by the US Geological Survey. Data deposited at the US Geological Survey's John Wesley Powell Center for Analysis and Synthesis. The authors declare no competing financial interests. This manuscript is contribution #541 of the USGS Amphibian Research and Monitoring Initiative. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Comments from D. Hocking, P. Toschik and three anonymous reviewers improved the manuscript.

International audience ; According to the Convention on Biological Diversity, by 2020 invasive alien species (IAS) should be identified and their impacts assessed, so that species can be prioritised for implementation of appropriate control strategies and measures put in place to manage invasion pathways. For one quarter of the IAS listed as the "100 of the world's worst", environmental impacts are linked to diseases of wildlife, undomesticated plants and animals. Moreover, IAS are a significant source of 'pathogen pollution' defined as the human-mediated introduction, often unintentional, of a pathogen to a new host or region. Despite this, little is known about the biology of alien pathogens and their biodiversity impacts after introduction into new regions. We argue that the threats posed by alien pathogens to endangered species, ecosystems, and ecosystem services should receive greater attention through legislation, policy and management. We identify ten key areas for research and action, including those relevant to the processes of introduction and establishment of an alien pathogen and to prediction of the spread and associated impact of an alien pathogen on native biota and ecosystems. The development of interdisciplinary capacity, expertise and coordination to identify and manage threats was seen as critical to address knowledge gaps.

According to the Convention on Biological Diversity, by 2020 invasive alien species (IAS) should be identified and their impacts assessed, so that species can be prioritized for implementation of appropriate control strategies and measures put in place to manage invasion pathways. For one quarter of the IAS listed as the "100 of the world's worst" environmental impacts are linked to diseases of wildlife (undomesticated plants and animals). Moreover, IAS are a significant source of "pathogen pollution" defined as the human-mediated introduction of a pathogen to a new host or region. Despite this, little is known about the biology of alien pathogens and their biodiversity impacts after introduction into new regions. We argue that the threats posed by alien pathogens to endangered species, ecosystems, and ecosystem services should receive greater attention through legislation, policy, and management. We identify 10 key areas for research and action, including those relevant to the processes of introduction and establishment of an alien pathogen and to prediction of the spread and associated impact of an alien pathogen on native biota and ecosystems. The development of interdisciplinary capacity, expertise, and coordination to identify and manage threats was seen as critical to address knowledge gaps. ; The workshop was an activity of COST Action TD1209: ALIEN Challenge. COST (European Cooperation in Science and Technology) is a pan‐European intergovernmental framework. The mission of COST is to enable scientific and technological developments leading to new concepts and products and thereby contribute to strengthening Europe's research and innovation capacities. Additional support for HR, HH, and BVP was received from the NERC Centre for Ecology & Hydrology National Capability allocation (Project NEC05100 HARM: Frameworks for Horizon‐scanning And Risk Mitigation of pathogens and invasive alien species (IAS) in changing UK and European environments) under the Natural Hazards Science Area. JP was partly supported by long‐term research development project RVO 67985939 (The Czech Academy of Sciences). ; Peer reviewed

Acknowledgments The workshop was an activity of COST Action TD1209: ALIEN Challenge. COST (European Cooperation in Science and Technology) is a pan-European intergovernmental framework. The mission of COST is to enable scientific and technological developments leading to new concepts and products and thereby contribute to strengthening Europe's research and innovation capacities. Additional support for HR, HH, and BVP was received from the NERC Centre for Ecology & Hydrology National Capability allocation (Project NEC05100 HARM: Frameworks for Horizon-scanning And Risk Mitigation of pathogens and invasive alien species (IAS) in changing UK and European environments) under the Natural Hazards Science Area. JP was partly supported by long-term research development project RVO 67985939 (The Czech Academy of Sciences). ; Peer reviewed ; Publisher PDF

According to the Convention on Biological Diversity, by 2020 invasive alien species (IAS) should be identified and their impacts assessed, so that species can be prioritized for implementation of appropriate control strategies and measures put in place to manage invasion pathways. For one quarter of the IAS listed as the "100 of the world's worst" environmental impacts are linked to diseases of wildlife (undomesticated plants and animals). Moreover, IAS are a significant source of "pathogen pollution" defined as the human-mediated introduction of a pathogen to a new host or region. Despite this, little is known about the biology of alien pathogens and their biodiversity impacts after introduction into new regions. We argue that the threats posed by alien pathogens to endangered species, ecosystems, and ecosystem services should receive greater attention through legislation, policy, and management. We identify 10 key areas for research and action, including those relevant to the processes of introduction and establishment of an alien pathogen and to prediction of the spread and associated impact of an alien pathogen on native biota and ecosystems. The development of interdisciplinary capacity, expertise, and coordination to identify and manage threats was seen as critical to address knowledge gaps.

According to the Convention on Biological Diversity, by 2020 invasive alien species (IAS) should be identified and their impacts assessed, so that species can be prioritised for implementation of appropriate control strategies and measures put in place to manage invasion pathways. For one quarter of the IAS listed as the "100 of the world's worst", environmental impacts are linked to diseases of wildlife, undomesticated plants and animals. Moreover, IAS are a significant source of 'pathogen pollution' defined as the human-mediated introduction, often unintentional, of a pathogen to a new host or region. Despite this, little is known about the biology of alien pathogens and their biodiversity impacts after introduction into new regions. We argue that the threats posed by alien pathogens to endangered species, ecosystems, and ecosystem services should receive greater attention through legislation, policy and management. We identify ten key areas for research and action, including those relevant to the processes of introduction and establishment of an alien pathogen and to prediction of the spread and associated impact of an alien pathogen on native biota and ecosystems. The development of interdisciplinary capacity, expertise and coordination to identify and manage threats was seen as critical to address knowledge gaps.

According to the Convention on Biological Diversity, by 2020 invasive alien species (IAS) should be identified and their impacts assessed, so that species can be prioritized for implementation of appropriate control strategies and measures put in place to manage invasion pathways. For one quarter of the IAS listed as the "100 of the world's worst" environmental impacts are linked to diseases of wildlife (undomesticated plants and animals). Moreover, IAS are a significant source of "pathogen pollution" defined as the human-mediated introduction of a pathogen to a new host or region. Despite this, little is known about the biology of alien pathogens and their biodiversity impacts after introduction into new regions. We argue that the threats posed by alien pathogens to endangered species, ecosystems, and ecosystem services should receive greater attention through legislation, policy, and management. We identify 10 key areas for research and action, including those relevant to the processes of introduction and establishment of an alien pathogen and to prediction of the spread and associated impact of an alien pathogen on native biota and ecosystems. The development of interdisciplinary capacity, expertise, and coordination to identify and manage threats was seen as critical to address knowledge gaps.

According to the Convention on Biological Diversity, by 2020 invasive alien species (IAS) should be identified and their impacts assessed, so that species can be prioritized for implementation of appropriate control strategies and measures put in place to manage invasion pathways. For one quarter of the IAS listed as the "100 of the world's worst" environmental impacts are linked to diseases of wildlife (undomesticated plants and animals). Moreover, IAS are a significant source of "pathogen pollution" defined as the human-mediated introduction of a pathogen to a new host or region. Despite this, little is known about the biology of alien pathogens and their biodiversity impacts after introduction into new regions. We argue that the threats posed by alien pathogens to endangered species, ecosystems, and ecosystem services should receive greater attention through legislation, policy, and management. We identify 10 key areas for research and action, including those relevant to the processes of introduction and establishment of an alien pathogen and to prediction of the spread and associated impact of an alien pathogen on native biota and ecosystems. The development of interdisciplinary capacity, expertise, and coordination to identify and manage threats was seen as critical to address knowledge gaps

Changing climate will impact species' ranges only when environmental variability directly impacts the demography of local populations. However, measurement of demographic responses to climate change has largely been limited to single species and locations. Here we show that amphibian communities are responsive to climatic variability, using >500,000 time-series observations for 81 species across 86 North American study areas. The effect of climate on local colonization and persistence probabilities varies among eco-regions and depends on local climate, species life-histories, and taxonomic classification. We found that local species richness is most sensitive to changes in water availability during breeding and changes in winter conditions. Based on the relationships we measure, recent changes in climate cannot explain why local species richness of North American amphibians has rapidly declined. However, changing climate does explain why some populations are declining faster than others. Our results provide important insights into how amphibians respond to climate and a general framework for measuring climate impacts on species richness. ; John Wesley Powell Center for Analysis and Synthesis - US Geological Survey ; U.S. Geological Survey-Amphibian Research and Monitoring Initiative (ARMI) ; U.S. Fish and Wildlife Service ; National Park Service ; U.S. Forest Service ; National Science Foundation [DEB-0841758, DEB-1149308] ; National Institutes of Health [R01GM109499] ; National Geographic Society ; Morris Animal Foundation ; David and Lucille Packard Foundation ; This work was conducted as part of the Amphibian Decline Working Group supported by the John Wesley Powell Center for Analysis and Synthesis, funded by the US Geological Survey. Funding and logistical support for field data collection came from a range of sources including the U.S. Geological Survey-Amphibian Research and Monitoring Initiative (ARMI), U.S. Fish and Wildlife Service, National Park Service, U.S. Forest Service, National Science Foundation (DEB-0841758, DEB-1149308), National Institutes of Health (R01GM109499), National Geographic Society, Morris Animal Foundation, and David and Lucille Packard Foundation. Data are deposited at the U.S. Geological Survey's John Wesley Powell Center for Analysis and Synthesis. This manuscript is contribution 654 of USGS ARMI. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government.