Meeting Abstract

P2.17  Wednesday, Jan. 5  Sensory basis of habitat recognition in echolocating bats GREIF, Stefan*; SIEMERS, Bj√∂rn M.; Max Planck Institute for Ornithology, Seewiesen, Germany greif@orn.mpg.de

Habitat recognition is vital for bats, as they are especially adapted in their use of echolocation to certain niches. How bats distinguish between certain habitat types is not yet understood. Bodies of water represent a special case of habitat; they are used not only for drinking, but also for foraging and as landmarks for orientation. We investigated the hypothesis that bats recognize water surfaces echo-acoustically by relying on their mirror-like acoustic reflection properties. We mimicked the surface of water using smooth plates and presented them to the bats simultaneously with textured ones of the same material. Our experimental data suggest that (1) bats recognize water surfaces echo-acoustically by being encoded as an acoustically smooth, extended surface, (2) this recognition pattern is extremely stereotypical and innate and (3) it is widely spread across European bat species and families and thus likely will be universal in bats. (4) The minimum critical size for a smooth surface to be taken for water depended on the maneuverability and sonar foot print of the tested species. (5) Bats used a weighted integrational mechanism to assess the presented multisensory situation and make a decision whether to drink or not.