Are bats able to sniff out their roosts?
|Fakulta / Pracoviště MU|
|Popis||To optimize the roosts searching strategies, bats need an extensive knowledge of a wide spectrum of suitable roosts and they should be able to identify and discriminate between them. Mainly vocalizations being heard from inside of the roosts or from its surroundings have been described as main cues in the recognition process. However, the use of chemical signals by animals may represent the oldest form of communication and especially in bats, due to their nocturnal activity, olfactory cues are likely to be an important mode of gathering information. In tree-dwelling bats a lots of their faeces and urine are being left near the entries to the roosts which are changed by some bat species very often. For that reason the importance of faeces and urine as olfactory signals used for discrimination between bat roosts was tested in the soprano pipistrelle (Pipistrellus pygmaeus). For odour preference tests, we used two different methods i) the bats were let to sniff the olfactory signal in a wooden cage with the walls made of a wire mesh and ii) experimental equipment was represented by an Y-maze with two olfactory signals in the different arms of the maze. It was shown that bats payed more attention to the signals in an Y-maze. Therefore this design was used in later sessions. Adult females performed higher searching activity in tests with conspecific roosts compared to that with the scents of heterospecific roosts of the sibling species, Pipistrellus pipistrellus. It seems that this discrimination ability is also displayed in relation to their own species, i. e. at the intraspecific level examining different colonies. On the contrary, juvenile females at the age of three months are not capable of such discrimination. These results indicate that females learn the discrimination ability later in their ontogeny. The project was sponsored by the Long-term Research Project No MSM0021622416.|