Predation of wood mice (Apodemus sylvaticus) on hibernating bats

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Swarming behaviour, catchment area and seasonal movement patterns of the Bechstein's bats : implications for conservation

Bats display marked seasonality throughout the temperate zone and use different habitats during different parts of the year. Unfortunately, detailed information regarding seasonal distribution and movements is often lacking, thereby hampering the development of adequate conservation measures. In this study we used radio telemetry to track females of the endangered Bechstein’s bat (Myotis bechsteinii) from autumn swarming sites to their summer maternity colony ranges. We were able to tag 22 individuals, 18 of which were subsequently recovered at nine roost sites up to 20.6 km away. Females from multiple colonies visited the same swarming site on a single night. Concurrently, we recovered females from a single maternity colony at different swarming sites on the same night. The catchment area of the investigated swarming sites measured 27.1 km2, and was skewed to the northwest. Tagged bats were recovered in forest fragments ranging in size from 5.42 to 128.98 ha. Notably, all but one of the recovered roosts were found in forests that have been continuously wooded since at least 1775. Surveys during the summer at these sites confirmed the presence of maternity colonies at six out of seven locations that could be investigated. Our study contributes to our understanding of swarming behavior and seasonal movement patterns, and exemplifies how these can be used to complete the year-round habitat use of bat species

Host phylogeny, geographic overlap, and roost sharing shape parasite communities in European bats

How multitrophic relationships between wildlife communities and their ectoparasitic vectors interact to shape the diversity of vector-borne microorganisms is poorly understood. Nested levels of dependence among microbes, vectors, and vertebrate hosts may have complicated effects on both microbial community assembly and evolution. We examined Bartonella sequences from European bats and their ectoparasites with a combination of network analysis, Bayesian phylogenetics, tip-association and cophylogeny tests, and linear regression to understand the ecological and evolutionary processes that shape parasite communities. We detected seven batectoparasite-Bartonella communities that can be differentiated based on bat families and roosting patterns. Tips of the Bartonella tree were significantly clustered by host taxonomy and geography. We also found significant evidence of evolutionary congruence between bat host and Bartonella phylogenies, indicating that bacterial species have evolved to infect related bat species. Exploring these ecological and evolutionary associations further, we found that sharing of Bartonella species among bat hosts was strongly associated with host phylogenetic distance and roost sharing and less strongly with geographic range overlap. Ectoparasite sharing between hosts was strongly predicted by host phylogenetic distance, roost sharing, and geographic overlap but had no additive effect on Bartonella sharing. Finally, historical Bartonella host-switching was more frequent for closely related bats after accounting for sampling bias among bat species. This study helps to disentangle the complex ecology and evolution of Bartonella bacteria in bat species and their arthropod vectors. Our work provides insight into the important mechanisms that partition parasite communities among hosts, particularly the effect of host phylogeny and roost sharing, and could help to elucidate the evolutionary patterns of other diverse vector-borne microorganisms

Host Phylogeny, Geographic Overlap, and Roost Sharing Shape Parasite Communities in European Bats

How multitrophic relationships between wildlife communities and their ectoparasitic vectors interact to shape the diversity of vector-borne microorganisms is poorly understood. Nested levels of dependence among microbes, vectors, and vertebrate hosts may have complicated effects on both microbial community assembly and evolution. We examined Bartonella sequences from European bats and their ectoparasites with a combination of network analysis, Bayesian phylogenetics, tip-association and cophylogeny tests, and linear regression to understand the ecological and evolutionary processes that shape parasite communities. We detected seven bat–ectoparasite–Bartonella communities that can be differentiated based on bat families and roosting patterns. Tips of the Bartonella tree were significantly clustered by host taxonomy and geography. We also found significant evidence of evolutionary congruence between bat host and Bartonella phylogenies, indicating that bacterial species have evolved to infect related bat species. Exploring these ecological and evolutionary associations further, we found that sharing of Bartonella species among bat hosts was strongly associated with host phylogenetic distance and roost sharing and less strongly with geographic range overlap. Ectoparasite sharing between hosts was strongly predicted by host phylogenetic distance, roost sharing, and geographic overlap but had no additive effect on Bartonella sharing. Finally, historical Bartonella host-switching was more frequent for closely related bats after accounting for sampling bias among bat species. This study helps to disentangle the complex ecology and evolution of Bartonella bacteria in bat species and their arthropod vectors. Our work provides insight into the important mechanisms that partition parasite communities among hosts, particularly the effect of host phylogeny and roost sharing, and could help to elucidate the evolutionary patterns of other diverse vector-borne microorganisms

Pan-European Distribution of White-Nose Syndrome Fungus (Geomyces destructans) Not Associated with Mass Mortality

BACKGROUND: The dramatic mass mortalities amongst hibernating bats in Northeastern America caused by "white nose-syndrome" (WNS) continue to threaten populations of different bat species. The cold-loving fungus, Geomyces destructans, is the most likely causative agent leading to extensive destruction of the skin, particularly the wing membranes. Recent investigations in Europe confirmed the presence of the fungus G. destructans without associated mass mortality in hibernating bats in six countries but its distribution remains poorly known. METHODOLOGY/PRINCIPAL FINDINGS: We collected data on the presence of bats with white fungal growth in 12 countries in Europe between 2003 and 2010 and conducted morphological and genetic analysis to confirm the identity of the fungus as Geomyces destructans. Our results demonstrate the presence of the fungus in eight countries spanning over 2000 km from West to East and provide compelling photographic evidence for its presence in another four countries including Romania, and Turkey. Furthermore, matching prevalence data of a hibernaculum monitored over two consecutive years with data from across Europe show that the temporal occurrence of the fungus, which first becomes visible around February, peaks in March but can still be seen in some torpid bats in May or June, is strikingly similar throughout Europe. Finally, we isolated and cultured G. destructans from a cave wall adjacent to a bat with fungal growth. CONCLUSIONS/SIGNIFICANCE: G. destructans is widely found over large areas of the European continent without associated mass mortalities in bats, suggesting that the fungus is native to Europe. The characterisation of the temporal variation in G. destructans growth on bats provides reference data for studying the spatio-temporal dynamic of the fungus. Finally, the presence of G. destructans spores on cave walls suggests that hibernacula could act as passive vectors and/or reservoirs for G. destructans and therefore, might play an important role in the transmission process

Macro-evolutionary trade-offs as the basis for the distribution of European bats

We have compiled a dataset of life history traits and distribution characteristics of 30 European bat species, based on a literature study of a total of 56 primary and secondary sources. These life history traits are grouped into morphological, physiological and ecological adaptations

Data from: Group size and dispersal ploys: An analysis of commuting behaviour of the pond bat (Myotis dasycneme)

This study aimed to provide a description on how Pond bats (Myotis dasycneme) disperse, how to recognize a commuting route, and details about the effort needed to make a complete survey of one commuting route. The study area covered the provinces of Zuid-Holland, Overijssel, Friesland, Noord-Holland, and Utrecht. During 6 years of study between 2002 and 2009, researchers and bat volunteers studied pond bats along several waterways (all waterways wider than 10 m) between known roosts and their hunting areas. All the observations were made between April and September, starting 20 min before sunset. During the entire observation effort, the time (in hours and minutes) and direction of each bat was recorded. The time that each bat passed the observation location was later transformed to minutes after sunset. The number of animals on commuting route was related to the number of animals present in their respective roost

Data from: Macro-evolutionary trade-offs as the basis for the distribution of European bats

We have compiled a dataset of life history traits and distribution characteristics of 30 European bat species, based on a literature study of a total of 56 primary and secondary sources. These life history traits are grouped into morphological, physiological and ecological adaptations

Data from: Predation of wood mice (Apodemus sylvaticus) on hibernating bats

In order to protect hibernating bats effectively, more knowledge about mortality factors is needed. This study proved the wood mouse (Apodemus sylvaticus) actively predates on bats. Fresh remains made by the wood mouse can be identified due to a typical pattern of lesions. This study was conducted in the province of Zuid-Holland, between the cities of Den Haag (The Hague), Leiden and the town of Wassenaar (between 52-070 and 52-090N, 4-180 and 4-210E). During a preliminary investigation with a trail camera, we were able to prove that wood mice actively searched for prey. Thereafter, remains of partially eaten bats have been collected and inspected in the laboratory. Bats which had not died of predation were excluded from the analysis. The remains that we found showed the typical pattern of lesions attributable to predation by wood mice. The skin of the victims is scraped clean. In the process of eating all the soft tissue, the skin is turned inside out, including the skin around the skull and hind legs. We found a total of 214 remains of predated bats during the 12 years. The resulting data are presented in this dataset