Grzegorz Lesiński

Bat predation by tawny owls Strix aluco in differently human‐transformed habitats

Differences in the frequency with which bats feature in the diet of tawny owls Strix aluco were studied, as these relate to types of habitat occupied (i.e. urban park, suburban forest, non‐urban land outside forest, and non‐urban forest as divided into forest edge or forest interior). The pellets collected at 152 sites in central and north‐eastern Poland in the years 1990–2008 comprised 17,908 items of vertebrate prey, of which 115 (0.64%) were bats. Tawny owls caught 11 bat species, most frequently Nyctalus noctula, Plecotus auritus and Eptesicus serotinus. The analysis revealed habitat‐related differences to the proportions of all tawny owl prey items accounted for by bats, being the highest in urban habitats (2.0%) and suburban forests (0.8%), and the lowest in forest interiors (0.1%). Bat frequency in the diet of tawny owls correlated negatively with that of other mammals pooled together with amphibians. Myotis nattereri and “aerial hawkers” (vs. “gleaners”) were taken significantly more often in habitats associated with a large city (parks and suburban forests), and P. auritus in non‐urban habitats.

Population genetics and bat rabies: a case study of Eptesicus serotinus in Poland

The serotine bat, Eptesicus serotinus is the most frequently rabies-infected (European bat lyssavirus 1-type, EBLV-1) bat species in Europe. To confirm Lyssavirus infection of this bat in Poland, we tested for the presence of rabies virus RNA from oropharyngeal swabs using RT-PCR. There was a 0.9% (two out of 212 individuals) level of infection within the overall population of serotine bats studied. However, an appreciation of the potential for pathogen transmission and disease risk requires an understanding of the dispersal of the primary host, and any large-scale geographic barriers that may impede gene flow. Thus, we also studied the patterns of bat dispersal via population genetics using nuclear (seven microsatellite loci) and mitochondrial (mtDNA control region) markers, examined in 12 subpopulations distributed across the country. Molecular analyses of microsatellite loci indicated high genetic diversity at all sites (heterozygosity observed, H o = 0.53–0.78), and extremely weak genetic structure in the Polish population of the species. The overall F ST was 0.012 (95% confidence interval: 0.006–0.020), and pairwise values ranged from 0.00 to 0.05. Only 22% of individuals were assigned to the subpopulation from which they were sampled. The Bayesian approach implemented in STRUCTURE also confirmed that all examined subpopulations should be treated as a single group, indicating a high level of gene flow. There was some evidence for female philopatry (genetic differentiation was greater in maternally-inherited mtDNA than nuclear DNA) and male-biased dispersal, e.g., H o and the variance of mean assignment were significantly higher in males than in females. Twelve individuals (seven females and five males) were identified as potential first generation migrants. Their migration routes ranged from 60–283 km in females ( ± SE = 177.9 ± 29.37) to 27–385 km in males (206.4 ± 58.95); surprisingly, no sexual differences were observed and this finding suggests that female-mediated gene flow may occur. MtDNA also produced a strong genetic signal for the demographic expansion (Fus F S statistics, F S = -26.30, P < 0.01 and a star-shaped haplotype network), which took place roughly 33,000 years BP, i.e., before the Last Glacial Maximum. The genetic uniformity of the Polish population implies that there is no migration barrier to EBLV-1, at least within the country, and the potential threat of rabies virus spreading via migration of infected animals may be higher than previously thought.

Long-term changes in abundance of bats as revealed by their frequency in tawny owls’ diet

Percentage of bats in tawny owls’ diet was compared in three periods: I — before 1976, II — 1976–1992, III — 1993–2009, by using the published and unpublished material from Poland (only samples over 100 vertebrate prey items). This species of owl showed an opportunistic predation on bats and took them more frequently in periods of higher abundance. Before the mass use of toxic pesticides in Poland, in the period I bats constituted more than 2% of vertebrates in four out of five diet samples (median 2.4%). The lowest bat abundance occurred in Poland in the 1980s and resulted in the lowest percentage of bats taken by owls in the period II (n = 11, median 0.2%). Due to the recovery of bat populations in the period III, the percentage of bats in tawny owls’ diet increased (n = 23, median 0.7%). In large samples (over 200 vertebrate items, n = 21) collected in central and north-eastern Poland the percentage of bats increased from 1980 to 2009 (the estimated average value at the end of that period slightly exceeded 1%). Samples collected at the same five sites in 1975–1992 and again in 2000–2009, confirmed the increasing trend in percentage of bats captured by tawny owls noted in last years.

Flight activity of serotine Eptesicus serotinus on organic and conventional farms in central Poland

A study, conducted on five pairwise selected farms (organic and conventional) in central Poland revealed higher flight activity (including foraging) of the serotine Eptesicus serotinus on organic farms. The median time in which bats were recorded by an ultrasound detector was ca. twice longer on organic farms as compared to conventional farms, with statistically important differences for sites situated close to farm buildings. On organic farms, bat activity was higher in housing zones as compared to open fields. Organic farming can improve foraging areas for serotines in the agricultural landscape. Penkiuose ekologiniuose ir penkiuose tradiciniuose ūkiuose centrinėje Lenkijos dalyje ultragarsiniais detektoriais atlikti tyrimai parodė didesnį vėlyvojo siksnio (Eptesicus serotinus) skraidymo ir maitinimosi aktyvumą ekologiniuose ūkiuose – vidutinė aktyvumo trukmė juose buvo beveik dvigubai ilgesnė. Statistiskai reiksmingi skirtumai nustatyti arti pastatų esanciose vietose. Vėlyvųjų siksnių aktyvumas buvo di...

Mammals in the vicinity of Rogów (central Poland)

Abstract: The aim of the study was the inventory of mammals in the vicinity of Rogow. In the years 2000–2011 most of the standard methods for such explorations were used (i.e. live-trapping, pellet analyses, tracking). Additionally, literature data, as well as unpublished data, were analysed. Another source of information was the collection of mounted mammals of Forest and Wood Museum in Rogow. Altogether, 51 mammals from 7 orders were recorded. This included 7 alien species (muskrat, brown rat, eastern house mouse, rabbit, American mink, raccoon dog, fallow deer). Another two species were anthropogenic predators (domestic cat and dog). Abundance trends analyses were done for the selected species i.e. brown hare, rabbit, common hamster and red deer numbers decreased while beaver, wild boar, red fox and raccoon dog increased. In XXI century only one species from the Polish Red Data Book of Animals was recorded (Leisler’s bat). Another important information was the record of the most northern present locality of common hamster in Poland.

Increasing bat abundance in a major winter roost in central Poland over 30 years

Abstract A bat census in the years 1981–2010 (repeated twice during each hibernation period in January and March) showed upward trends in many populations of bats hibernating in the Szachownica Cave (central Poland). Total numbers of the bat assemblage, which consisted of 11 species, increased within the study period from 178 to 1477 individuals in the first decade to 835–2902 in the past decade of the study, with the highest rates of increase noted in Barbastella barbastellus, Plecotus auritus and Myotis nattereri. Myotis myotis and Myotis daubentonii showed only slight upward trends. In the years 2009–2010, Myotis bechsteinii occurred in markedly higher numbers (up to 24 individuals) as compared to previous years.