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Expanding digital data sources, including social media and online news, provide a low-cost way to examine human-nature interactions, such as wildlife exploitation. However, the extent to which using such data sources can expand or bias understanding of the distribution and intensity of threats has not been comprehensively assessed. To address this gap, we quantified the geographical and temporal distribution of online sources documenting the hunting and trapping, consumption, or trade of bats (Chiroptera) and compared these with the distribution of studies obtained from a systematic literature search and species listed as threatened by exploitation on the International Union for Conservation of Nature Red List. Online records were collected using automated searches of Facebook, Twitter, Google, and Bing and were filtered using machine classification. This yielded 953 relevant social media posts and web pages, encompassing 1099 unique records of bat exploitation from 84 countries. Although the number of records per country was significantly predicted by the number of academic studies per country, online records provided additional locations and more recent records of bat exploitation, including 22 countries not present in academic literature. This demonstrates the value of online resources in providing more complete geographical representation. However, confounding variables can bias the analysis of spatiotemporal trends. Online bat exploitation records showed peaks in 2020 and 2014, after accounting for increases in internet users through time. The second of these peaks could be attributed to the COVID-19 outbreak, and speculation about the role of bats in its epidemiology, rather than to true changes in exploitation. Overall, our results showed that data from online sources provide additional knowledge on the global extent of wildlife exploitation, which could be used to identify early warnings of emerging threats and pinpoint locations for further research., (© 2024 Society for Conservation Biology.)

The greater horseshoe bat (Rhinolophus ferrumequinum) is among the most widespread bat species in Europe but it has experienced severe declines, especially in Northern Europe. This species is listed Near Threatened in the European IUCN Red List of Threatened Animals, and it is considered to be highly sensitive to human activities and particularly to habitat fragmentation. Therefore, understanding the population boundaries and demographic history of populations of this species is of primary importance to assess relevant conservation strategies. In this study, we used 17 microsatellite markers to assess the genetic diversity, the genetic structure, and the demographic history of R. ferrumequinum colonies in the western part of its distribution. We identified one large population showing high levels of genetic diversity and large population size. Lower estimates were found in England and northern France. Analyses of clustering and isolation by distance suggested that the Channel and the Mediterranean seas could impede R. ferrumequinum gene flow. These results provide important information to improve the delineation of R. ferrumequinum management units. We suggest that a large management unit corresponding to the population ranging from Spanish Basque Country to northern France must be considered. Particular attention should be given to mating territories as they seem to play a key role in maintaining high levels of genetic mixing between colonies. Smaller management units corresponding to English and northern France colonies must also be implemented. These insular or peripheral colonies could be at higher risk of extinction in the near future. [ABSTRACT FROM AUTHOR]

The age profile of populations fundamentally affects their conservation status. Yet, age is frequently difficult to assess in wild animals. Here, we assessed the use of DNA methylation of homologous genes to establish the age structure of a rare and elusive wild mammal: the Bechstein's bat (Myotis bechsteinii). We collected 62 wing punches from individuals whose ages were known as a result of a long‐term banding study. DNA methylation was measured at seven CpG sites from three genes, which have previously shown age‐associated changes in humans and laboratory mice. All CpG sites from the tested genes showed a significant relationship between DNA methylation and age, both individually and in combination (multiple linear regression R2 = 0.58, p < 0.001). Despite slight approximation around estimates, the approach is sufficiently precise to place animals into practically useful age cohorts. This method is of considerable practical benefit as it can reliably age individual bats. It is also much faster than traditional capture–mark–recapture techniques, with the potential to collect information on the age structure of an entire colony from a single sampling session to better inform conservation actions for Bechstein's bats. By identifying three genes where DNA methylation correlates with age across distantly related species, this study also suggests that the technique can potentially be applied across a wide range of mammals. [ABSTRACT FROM AUTHOR]

Background: The structuring of wild animal populations can influence population dynamics, disease spread, and information transfer. Social network analysis potentially offers insights into these processes but is rarely, if ever, used to investigate more than one species in a community. We therefore compared the social, temporal and spatial networks of sympatric Myotis bats (M. nattereri (Natterer's bats) and M. daubentonii (Daubenton's bats)), and asked: (1) are there long-lasting social associations within species? (2) do the ranges occupied by roosting social groups overlap within or between species? (3) are M. daubentonii bachelor colonies excluded from roosting in areas used by maternity groups? Results: Using data on 490 ringed M. nattereri and 978 M. daubentonii from 379 colonies, we found that both species formed stable social groups encompassing multiple colonies. M. nattereri formed 11 mixed-sex social groups with few (4.3%) inter-group associations. Approximately half of all M. nattereri were associated with the same individuals when recaptured, with many associations being long-term (>100 days). In contrast, M. daubentonii were sexually segregated; only a quarter of pairs were associated at recapture after a few days, and inter-sex associations were not long-lasting. Social groups of M. nattereri and female M. daubentonii had small roost home ranges (mean 0.2 km2 in each case). Intra-specific overlap was low, but inter-specific overlap was high, suggesting territoriality within but not between species. M. daubentonii bachelor colonies did not appear to be excluded from roosting areas used by females. Conclusions: Our data suggest marked species- and sex-specific patterns of disease and information transmission are likely between bats of the same genus despite sharing a common habitat. The clear partitioning of the woodland amongst social groups, and their apparent reliance on small patches of habitat for roosting, means that localised woodland management may be more important to bat conservation than previously recognised. [ABSTRACT FROM AUTHOR]

The water vole (Arvicola amphibius) is Britain's most endangered mammal, having gained protection under Schedule 5 of the Wildlife and Countryside Act in 2008. We present an overview of a range of naturally occurring pathogens and parasites in this rare species, which might negatively impact population persistence for small or declining populations. Wild water voles were livecaptured in 2004 and 2006 from sites throughout the UK and were screened for a range of pathogens. These included: Puumala virus, Campylobacter spp., Escherichia coli, Salmonella enterica, Leptospira spp., Bartonella spp., Toxoplasma gondii, Giardia spp., Cryptosporidium spp., Babesia microti and Trypanosoma spp. E. coli was the most prevalent with 46/74 (62.2%; 95% CI, 51-73) individuals infected. One vole was co-infected with seven different pathogens whilst 20% of individuals were pathogen-free. [ABSTRACT FROM AUTHOR]