Alcathoe Bat (Myotis alcathoe) in the Czech Republic: Distributional Status, Roosting and Feeding Ecology

The northernmost findings of the Alcathoe bat (Myotis alcathoe von Helversen & Heller, 2001) in Poland

The Alcathoe bat Myotis alcathoe (von Helversen, Heller, 2001) is a newly described species of the cryptic complex of whiskered bat species living in sympatry across Europe. The habitats preferred by this species are natural, moist and deciduous forests with old trees and water streams. The majority of known locations of this species come from highlands, foothills and mountainous regions while practically not occurring in the lower elevations. They come mainly from cave areas, where bats were caught during autumn swarming, while records in other seasons are much less frequent. Currently, individual sites in Poland also come from lowlands, beyond the range of the mountains and uplands, which indicates a possible wider range of this species. The bats were captured using mist-nests in the Silesian Lowlands for three consecutive years (2013–2015). The localities were placed in various forest environments, ranging in elevation from 100 to 260 m a.s.l. Bats were initially identified based on morphological features, then the correctness of identification was confirmed by molecular methods. Two females and five males of Myotis alcathoe were captured into four new locations from the lowlands of Poland: Przemków, Głębowice, Chodlewo, and Dalkowskie Jary (Silesian Lowland). Old trees and a small watercourse were important elements in all these locations. Currently, these findings are the northernmost locations of the species in Poland and one of the northernmost locations in Central Europe. The latest findings of the species are located about 50 km to the south, but the vast majority of the rest of locations is from the foothills belt. This finding suggests that the species may inhabit regions much further north than previously suggested, and the limiting factor is the presence of old trees in wet environments.

Babesia vesperuginis, a neglected piroplasmid: new host and geographical records, and phylogenetic relations

BACKGROUND

Babesia spp. are hemoparasites which infect the red blood cells of a large variety of mammals. In bats, the only known species of the genus is Babesia vesperuginis. However, except a few old reports, the host range and geographical distribution of this bat parasite have been poorly studied. This study aimed to investigate the presence of piroplasms in tissues of bats collected in four different countries from eastern and central Europe: Austria, Czech Republic, Hungary and Romania.

METHODS

A total of 461 bat carcasses (24 species) were collected between 2001 and 2016 from caves, mines and buildings. PCR was performed using specific primers targeting a portion of the 18S rDNA nuclear gene and cytochrome c oxidase subunit 1 mitochondrial gene, followed by sequencing.

RESULTS

The results of this study show for the first time the presence of B. vesperuginis in bats in central and eastern Europe. The phylogenetic analysis of the 18S rDNA nuclear gene revealed no variability between the sequences and the phylogenetic analysis of the cox1 mitochondrial gene proved that B. vesperuginis could be divided into two subclades.

CONCLUSION

Our study showed a broad geographical distribution of B. vesperuginis in European bats, reporting its presence in five new host species (M. cf. alcathoe, M. bechsteinii, M. myotis, Pi. nathusii and V. murinus) and three new countries.

Hybridization hotspots at bat swarming sites

During late summer and early autumn in temperate zones of the Northern Hemisphere, thousands of bats gather at caves, mainly for the purpose of mating. We demonstrated that this swarming behavior most probably leads not only to breeding among bats of the same species but also interbreeding between different species. Using 14 nuclear microsatellites and three different methods (the Bayesian assignment approaches of STRUCTURE and NEWHYBRIDS and a principal coordinate analysis of pairwise genetic distances), we analyzed 375 individuals belonging to three species of whiskered bats (genus Myotis) at swarming sites across their sympatric range in southern Poland. The overall hybridization rate varied from 3.2 to 7.2%. At the species level, depending on the method used, these values ranged from 2.1-4.6% in M. mystacinus and 3.0-3.7% in M. brandtii to 6.5-30.4% in M. alcathoe. Hybrids occurred in about half of the caves we studied. In all three species, the sex ratio of hybrids was biased towards males but the observed differences did not differ statistically from those noted at the population level. In our opinion, factors leading to the formation of these admixed individuals and their relatively high frequency are: i) swarming behaviour at swarming sites, where high numbers of bats belonging to several species meet; ii) male-biased sex ratio during the swarming period; iii) the fact that all these bats are generally polygynous. The highly different population sizes of different species at swarming sites may also play some role. Swarming sites may represent unique hybrid hotspots, which, as there are at least 2,000 caves in the Polish Carpathians alone, may occur on a massive scale not previously observed for any group of mammal species in the wild. Evidently, these sites should be treated as focal points for the conservation of biodiversity and evolutionary processes.