Pond bat
Myotis dasycneme
The pond bat is a medium-sized European bat species closely associated with large, open water bodies. It prefers hunting at low altitudes over canals, rivers, and lakes, targeting water-associated insects. A characteristic feature is its remarkably large feet, which are an adaptation for catching prey directly from the water surface. The species is a typical lowland inhabitant, using buildings as summer roosts and caves or mines for hibernation.
Details
Identification
Large feet (over 10 mm), grayish-brown dorsal fur, sharply demarcated whitish-gray underside, ears with a short, blunt tragus.
Social behavior
Forms social nursery colonies of females in summer; males usually live solitarily or in small bachelor groups.
Diet
Specialized in water-associated insects, particularly non-biting midges (Chironomidae), caddisflies, and occasionally small moths.
Hunting strategy
Trawling hunting style; catches insects in flight directly from the water surface using its large feet or uropatagium.
Overwintering
Hibernation in humid, frost-free underground quarters such as caves, mines, bunkers, or cellars.
Ecology
Ecological role
Important predator for insect populations in wetlands; contributes to the biological control of midges.
Natural predators
Owls (e.g., barn owl), birds of prey, domestic cats (at roosts), and martens.
Competitor species
Daubenton's bat (Myotis daubentonii) due to similar hunting habitats and prey spectra.
Ecosystem service
Biological pest control through the consumption of large quantities of insects.
Threats
Loss of roosts due to building renovation, water pollution, pesticide use, and fragmentation of flight corridors by artificial light.
Scientific profile
Profile
Distinguishing features
Characteristic are the very large feet (over 10 mm in length), used for hunting on the water surface. The ears are relatively short and barely extend beyond the tip of the snout when laid forward. The tragus is narrow and about half the length of the ear.
Habitat
Prefers large, open water bodies such as lakes, wide canals, and slow-moving rivers as foraging areas. Maternity colonies are mostly located in buildings (attics), while winter quarters are found in humid caves, mines, or bunkers.
Diet
Opportunistic insectivores; main diet consists of non-biting midges (Chironomidae), caddisflies (Trichoptera), small moths, and occasionally aquatic crustaceans.
Protection & threats
Main threats
Loss of roosts due to energy-efficient building renovations, pesticide use in agriculture, water pollution, and light pollution along flight routes.
Population trend
Stable to slightly decreasing; classified as 'endangered' in Germany (Red List 2) due to dependence on specific roost types.
Conservation measures
Protection and preservation of maternity roosts in buildings, securing of winter quarters, promotion of insect-rich water bodies, creation of hedges as guiding structures.