Flexibility of vocalization usage in the bat Saccopteryx bilineata
Saccopteryx bilineata is a common Neotropical bat that lives in stable groups of up to 60 individuals with harem-like structures and peripheral males queuing for access to females (Bradbury & Vehrencamp 1976). To maintain this complex social group structure the bats need an appropriate communication system (Freeberg et al. 2012).
S. bilineata has a huge vocal repertoire of social calls which is already well described: starting from babblings bouts from pups (Knörnschild et al. 2006), to simple structured distress calls (Eckenweber & Knörnschild 2016) and screeches, stereotypical territorial songs and complex courtship songs from males (Behr & von Helversen 2004).
In my Ph.D. thesis, I study whether those highly social animals and vocal learners (Voigt et al. 2008, Knörnschild 2014) are able to adapt their vocal repertoire and the associated behavior to particular situations and change it over time and geographical range. Therefore I investigate different vocalization types and the associated behavior of S. bilineata in three different locations in Central America (Curú National Wildlife Refuge and National Park Santa Rosa in Costa Rica, Barro Colorado Island in Panama).
In particular I search for (1) local differences in the courtship songs and behavior of males, (2) for seasonal changes (i.e. over the course of the mating season) of female screeches and their influence on the male courtship behavior and (3) for differences in the responsiveness towards distress calls depending on the social context.