Web-building spiders and blood-feeding flies as prey of the notch-eared bat (Myotis emarginatus)

Conservation of the endangered notch-eared bat (M. emarginatus) requires a specific action plan based on precise ecological requirements of this species. The analysis of the diet of three colonies in southern Belgium revealed: (1) spatial and seasonal variations of the diet; (2) the consumption of web-building spiders (Araneus diadematus, Araneus triguttatus, Cyclosa conica, Enoplognatha sp., Larinioides patagiatus, Neriene emphana); (3) the predominance of blood-feeding dipterans in the diet (Stomoxys calcitrans and Musca autumnalis). Since the populations of these two ectoparasitic flies are sensitive to the use of antiparasitic drugs, these drugs should be used with caution by farmers and veterinarians in the vicinity of maternity colonies.