Olfactory discrimination between two cryptic species of bats Pipistrelluspipistrellus and P. pygmaeus

Abstract

Absence of accuracy in species recognition can lead to inter-specificmating and hybridization. Aside from acoustic signals, bats can also use olfactory signals to search for mates. We compared the level of attractiveness of facial glands scents and urinary scents for discrimination in two cryptic bat species. Both sexes of two sympatric bat species Pipistrellus pipistrellus and P. pygmaeus were used as model. Possible sexual preferences using two olfactory signals were studied in a dual choice experiment in a glass Y-maze. Both sexes, without reference to the species, performed lower searching activity in tests with urinary scents than in the case of signals composed of scents of facial glands. Males of both species were able to discriminate and prefer the odour of conspecific females, with small proportion of disassortative choices. Females of both species did not have species-specific preferences. Absence of females' odour preferences and small proportion of males' disassortative choices can provide theoretical background for the existence of inter-species hybridization orpoint at more important role of acoustic signals in pre-mating behaviour.