Long-Term Monitoring of Amphibian Populations of a National Park in Northern Spain Reveals Negative Persisting Effects of Ranavirus, but Not Batrachochytrium dendrobatidis

Amphibians are the most highly threatened vertebrates, and emerging pathogens are a serious threat to their conservation. Amphibian chytrid fungi and the viruses of the Ranavirus genus are causing disease outbreaks worldwide, including in protected areas such as National Parks. However, we lack information about their effect over amphibian populations in the long-term, and sometimes these mortality episodes are considered as transient events without serious consequences over longer time-spans. Here, we relate the occurrence of both pathogens with the population trends of 24 amphibian populations at 15 sites across a national Park in northern Spain over a 14-year period. Just one out 24 populations presents a positive population trend being free of both pathogens, while seven populations exposed to one or two pathogens experienced strong declines during the study period. The rest of the study populations (16) remain stable, and these tend to be of species that are not susceptible to the pathogen present or are free of pathogens. Our study is consistent with infectious diseases playing an important role in dictating amphibian population trends and emphasizes the need to adopt measures to control these pathogens in nature. We highlight that sites housing species carrying Ranavirus seems to have experienced more severe population-level effects compared to those with the amphibian chytrid fungus, and that ranaviruses could be just as, or more important, other more high-profile amphibian emerging pathogens

Collapse of amphibian communities due to an introduced ranavirus

© 2014 The Authors. The emergence of infectious diseases with a broad host range can have a dramatic impact on entire communities and has become one of the main threats to biodiversity [1-4]. Here, we report the simultaneous exploitation of entire communities of potential hosts with associated severe declines following invasion by a novel viral pathogen. We found two phylogenetically related, highly virulent viruses (genus Ranavirus, family Iridoviridae) causing mass mortality in multiple, diverse amphibian hosts in northern Spain, as well as a third, relatively avirulent virus. We document host declines in multiple species at multiple sites in the region. Our work reveals a group of pathogens that seem to have preexisting capacity to infect and evade immunity in multiple diverse and novel hosts, and that are exerting massive impacts on host communities. This report provides an exceptional record of host population trends being tracked in real time following emergence of a wildlife disease and a striking example of a novel, generalist pathogen repeatedly crossing the species barrier with catastrophic consequences at the level of host communities.This work was supported by Natural Environment Research Council grant NE/G011885/1, the Systematics and Taxonomy (SynTax) research scheme administered by the Linnean Society of London, the Fundacio´ n General CSIC, Banco Santander, and European Research Council grant 260801-BIG-IDEA.Peer Reviewe

Designing economic instruments to maintain and enhance hay meadows biodiversity in South-West Europe

Hay meadows, agri-ecosystems maintained by the secular actions of man, are disappearing all over Europe, and with them, large areas with high biodiversity. In recent years, this process has also affected significant surfaces of mesophile hay meadows located in South-West European (SW EU) mountain areas due to changes in land management and socio- demographic decline. Specific agri-environmental subsidies are one of the potential instruments to favour their conservation, but most of SW EU mountain areas lack them. This study aims to analyse how current agricultural payment schemes from CAP and Rural Development Programmes (RDP) can be used to enhance biodiversity conservation by promoting the maintenance/recovery of the traditional extensive management of mesophile hay meadows in Natura 2000 areas within SW EU territory. To reach this goal, an extensive review and characterisation of economic instruments and sectoral experiences applied to the conservation of these meadows in Europe has been carried out. In addition, a clustering and comparative analysis of their main features, transfer possibilities and implementation results have been addressed. As a result, this study proposes strategic guidelines to design and put into practice future economic measures to conserve mesophile hay meadows in different SW EU mountain protected areas.Authors thank EU Interreg SUDOE Programme and ERDF 2014-2020 for co-financing this study within the context of SOS PRADERAS Project (www.sospraderas.eu).info:eu-repo/semantics/publishedVersio