Michal Andreas

Diet composition and foraging activity of Pipistrellus pygmaeus in a floodplain forest

In 2000–2002 bat droppings were collected under the emerging crevice of a nursery colony of Pipistrellus pygmaeus. The locality was situated in a floodplain forest at the confluence of the Dyje and Morava rivers (S Moravia, Czech Republic). In total, 27 samples (20 pellets in one sample) of droppings were used to analyze prey remains. In the diet, 40 taxonomic groups of invertebrates were found. As expected, small dipteran insects were the main food item in which Nematocera dominated. Besides Chironomidae and Ceratopogonidae also a high percentage of nematoceran eggs were recorded. Surprisingly, a relatively high percentage of Brachycera was recorded. Further frequent prey items belonged to the orders of Trichoptera, Hymenoptera, Coleoptera and Sternorrhyncha. A heterodyne bat detector was used to follow foraging activity of P. pygmaeus on line transects in forest and water habitats in the vicinity of the colony. A significant decrease in foraging activity over water habitats and in forest sites during the late pregnancy (mid-May — early June) and an increase during the lactation and post-lactation periods (mid-June — early August) were found. Changes in the frequency of occurrence of Chironomidae, Neuroptera, Trichoptera, Aphidinea and Simuliidae were correlated with the bats’ foraging activity.

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

Between 2001 and 2008, we recorded Myotis alcathoe at nine sites within three distant areas in the Czech Republic. The species identification was confirmed with cyt b sequences and four distinct haplotypes were identified. All the localities exhibit surprisingly uniform habitat characteristics: (1) old full-grown oak-hornbeam forests, with (2) numerous large trees in advanced stages of decay are present, and (3) a very small to large water bodies and/or patches of riparian vegetation surrounded by the forest. Using radiotracking techniques, we discovered 27 day roosts of M. alcathoe, located mostly in big oak, birch and lime trees inside extensive forest stands. All roosts were fissures or small cavities in a tree trunk and in branches in the canopies, some 16m above the ground. Bats preferred trees that were higher, had higher canopy and canopy basement and had larger diameter at breast height than other available trees. Roost trees were surrounded by lower trees with lower canopy basements than available trees. Roost trees were in a poorer condition than other available trees. Roosts were occupied by up to 83 individuals in July but usually single individuals were found in the roosts in September. In contrast to syntopic M. mystacinus and M. brandtii, M. alcathoe has never been found in an anthropogenic roost (except for a fissure in concrete electricity pole). Preliminary analysis of the diet showed that nematoceran flies were the most important prey item along with spiders, caddis flies, small moths and neuropterans. In the observed ecological characteristics, M. alcathoe markedly differs from other European species of the genus Myotis. Its restricted habitat requirements are perhaps responsible for an islet-like pattern of its distribution and suggest an essential conservation value of the habitats of its occurrence.

Body size as an important factor determining trophic niche partitioning in three syntopic rhinolophid bat species

We investigated a community of syntopically occurring horseshoe bats (Rhinolophus hipposideros, R. euryale, R. ferrumequinum) in southern Slovakia. The faecal pellets of these bat species were collected in the field and later analysed under a dissecting microscope. The three species studied are known to be very similar as far as their ecology, echolocation and preferred habitats are concerned, but they diverge significantly in their body sizes. In this study, all three species fed predominantly on moths [59–80 percentage frequency (%f); 87–95 percentage volume (%vol)], but their diet compositions differed in the size of individuals consumed. The smallest bat species (R. hipposideros) fed only on the smallest moths (%f = 59; %vol = 87), the medium-sized species (R. euryale) mainly on medium-sized moths (%f = 60; %vol = 74) and the largest one (R. ferrumequinum) especially on the largest moths (%f = 54; %vol = 89). Despite similar preferred habitat and the main prey category, the rates of trophic niche overlap were surprisingly low. The trophic niche percentage overlap was 7–31% (computed from %f data) and 1–20% (computed from %vol data), respectively and suggests an extraordinary importance of mere divergences of bats in their body sizes for trophic niche partitioning and stable species coexistence.

Dietary Composition, Resource Partitioning and Trophic Niche Overlap in Three Forest Foliage-Gleaning Bats in Central Europe

A diverse syntopic bat community was studied in Central Europe. The study was primarily aimed at forest bats utilizing a foliage-gleaning foraging strategy (Myotis nattereri, M. bechsteinii and Plecotus auritus). The results indicated the foliage-gleaning foraging strategy and the effective resource partitioning. Once a certain diet item comprises an important food resource for one bat species, it is usually exploited much less by the other two bat species, and despite important seasonal dietary changes this pattern lasts throughout the entire season. Dietary composition varies more among the entire guild of forest foliage-gleaning bats than it does between these species and their morphological siblings or evolutionarily related species (e.g., Plecotus auritus vs. P. austriacus or Barbastella barbastellus, Myotis nattereri vs. M. emarginatus). The results are not fully consistent with the predictions of sensory ecology, which presume that bats with longer ears feed more frequently on prey that generates sound. The results do not support the hypothesis that rare bats exploit a narrower range of prey. The relatively rare M. bechsteinii has a wider trophic niche, whereas the more common P. auritus exploits a narrower range of prey. Comparison of dietary composition and morphological and echolocation parameters indicates that larger species feed on harder prey, species with longer ears are moth-eating specialists and species with a higher call intensity exploit small dipterans, probably in uncluttered habitats.

The thousand-year history of the Slovak Karst inferred from pollen in bat guano inside the Domica Cave (Slovakia)

A thousand years old 105 cm deep deposit of bat guano in the Domica Cave (southern Slovakia, Slovak Karst National Park) has been discovered for science, and three samples were analysed for pollen to identify the bats’ preferred foraging habitats and for insect remains to identify their diet. The bat species concerned, Rhinolophus euryale, is rare in the area, which lies at the northern margin of its distribution. The pollen record captured alder forests between 897–1024 AD, temperate light broad-leaved oak-hornbeam forests with Quercus cerris, Fraxinus ornus, Cornus mas and Corylus avellana between 1522–1800 AD, and almost recently willow shrubs. This pattern may, however, reflect local changes in the surrounding landscape where the bats hunted. Pollen of anemophilous taxa was underrepresented (e.g. Fagus), while entomophilous taxa were overrepresented (e.g. Fraxinus ornus, Loranthus europaeus, Acer, Agrostemma githago). The phenology of the encountered pollen taxa indicates that the bats used the Domica Cave mainly as spring and summer roosts. The pollen record further indicates that the bats prefer to forage in a forest–steppe landscape with open Pannonian broadleaved forests and humid temperate riparian environments. Today, this kind of landscape does not occur further north, which may explain the northern limit of this bat species at the study site.

Designing Migration Corridors for Large Mammals in the Czech Republic

Abstract The presented article introduces methods and some results of a project aiming to improve the protection of landscape permeability for migration of large mammals. The main aim of the project was delimitation of migration corridors, representing an ecological network connecting areas of existing, or potential presence of focal species. Based on mapping of current and historical occurrence of selected species of large predators and ungulates, areas of potential presence of such species were defined, including further analysis of connectivity of these areas. At the same time, all categories of anthropogenic and natural barriers were described. Migration corridors were designed over detailed topographic datasets, according to the results of habitat analyses of both groups of animals, and subsequently were tested in the field. The project resulted in a coherent network of existing and proposed migration corridors, with sections categorised according to permeability, as well as methodical protection and a management plan

Monitoring of Biodiversity Changes in the Landscape Scale

Monitoring of Biodiversity Changes in the Landscape Scale The monitoring and evaluation of changes in biodiversity is a subject for many biological and ecological disciplines. Biodiversity loss has become a social and political issue over the last few decades, and protection of biological diversity has emerged as one of the main subjects within national nature conservation policies as well as international conventions, conservation targets and political programmes (e.g. the Convention on Biological Diversity, Target 2010, SEBI 2010, CITES, Ramsar Convention, European Landscape Convention). The establishment of a monitoring scheme based on an appropriate set of indicators is vital for precise assessment of the effectiveness of measures applied within biodiversity protection (e.g. action plans for endangered species, agro-environmental and landscape protection programmes). Many indicators of biodiversity change have been proposed, but their representativeness and applicability frequently suffer from poor available data or local circumstances. The concept of species and landscape diversity evaluation using a fixed set of indicators has been developing in other European countries for some two decades, but this approach is still sporadic in the Czech Republic. This paper provides a review of the current state of this topic in the Czech Republic, discusses the concept of establishing a future national biodiversity monitoring network, and proposes a self-contained set of indicators covering all organizational and spatial levels. These proposals will enable scientifically based and sufficiently accurate evaluation of existing trends in biodiversity and its projection into the future based on foreseeable land-use changes.

Current distribution and habitat preferences of red deer and Eurasian elk in the Czech Republic

Here we determine the distribution, numbers and habitat preferences of two of the largest species in the family Cervidae present in the Czech Republic, red deer and Eurasian elk. Red deer occurs predominantly in vast areas of forest, i.e. mainly in the mountains bordering this country and several large forest units in the interior. The range of this species has been increasing along with the size of its population. Areas of its permanent occurrence may be generally characterized as regions largely covered with deciduous and coniferous forests and pastures, and regions with a more diverse landscape. Red deer does not occur in areas that are mainly arable or urban, or in areas covered with extensive water bodies and wetlands. As these animals prefer large forests, they occur mainly at high altitudes where the terrain is rugged. The Eurasian elk permanently occurs in the Czech Republic in a single area located between the state border and the right bank of the Lipno Dam. Its home range has been diminishing, presumably along with its numbers. The area of its permanent occurrence is characterized by an abundance of coniferous trees, some pastures and water bodies. The Eurasian elk does not occur in areas covered with arable and urban land but also surprisingly in areas with mainly deciduous forest. Both species prefer high altitudes, but Eurasian elk prefers areas with little difference in the terrain vertically.