Emergence behaviour of the serotine bat (Eptesicus serotinus) under predation risk

0164310 - UBO-W 20020004 RIV NL eng J - Journal Article
Petrželková, Klára Judita - Zukal, Jan
Emergence behaviour of the serotine bat (Eptesicus serotinus) under predation risk.
Netherlands Journal of Zoology. Roc. 51, č. 4 (2001), s. 395-414. ISSN 0028-2960
R&D Projects: GA AV ČR IAC6087502; GA AV ČR KSK6005114
Institutional research plan: CEZ:AV0Z6093917
Keywords : Eptesicus serotinus * emergence * predation risk
Subject RIV: EG - Zoology
Impact factor: 0.509, year: 2001

Emergence activity of a maternity colony of Eptesicus serotinus was monitored from May to August 1997 and 1998 at Strelice, Czech Republic. We focused mainly on the impact of predation risk on emergence parameters, but the effects of reproductive and climatic factors were assessed too. Observations were made with 10-days intervals during two consecutive nights from which the first was a control and the second a treatment night. On treatment nights a stuffed specimen of Tyto alba (in 1997) or Falco tinnunculus (in 1998) was placed close to the roost exits and recorded calls of the particular species were played back towards the roost. In 1997 the bats emerged earlier during lactation than during gravidity, while in 1998 the trend was opposite. This could be explained by a different course of food availability in each year. During poor weather the number of emerged bats decreased and bats probably used an alternative roost. The predation risk did not affect the values of any emergence parameter but induced changes in relationships among emergence parameters. When bats emerged earlier and thus were exposed to increased potential predation pressure, they increased their degree of clustering to decrease the probability of being attacked. The perception of predation risk was not affected by weather conditions or reproductive period.
Permanent Link: http://hdl.handle.net/11104/0061531