Rado Seminar - Melina Dietzer + Hester Bronnvik

Melina Dietzer: Influence of olfactory cues on foraging behavior - Do bats use olfactory cues to find freshly mowed meadows?

Foraging is a difficult task for animals and is further complicated by humans through increasing agricultural activities. We investigated whether European insectivorous bats can adapt to human disturbance of their natural habitat, in this case, whether they show higher activity over freshly mowed meadows, which most likely provide an abundant foraging habitat. Indeed, we found that bats often forage over freshly mowed meadows. After we sprayed the scent of freshly mowed grass on unmowed meadows to simulate a mowing event, it was found that bat activity increased. This is the first evidence that insectivorous bats can associate the scent of freshly mowed grass with higher insect abundance and that they use olfactory cues to find freshly mowed meadows.

Hester Bronnvik: Experience does not change the importance of wind support for migratory route selection by a soaring bird

Migration is a risky and energetically expensive behavior during which safe, low-cost travel is key to survival and reproduction. Understanding how animals develop such vital behavior is fundamental to understanding their fitness. We can look at migratory routes as records of animals’ decisions; thus, by comparing routes of the same individuals over multiple years, we can study changes in decisions about migration—relative to the environment—as individuals gain experience. Using tracking data from a long-term study of European Honey Buzzards, I ask how the importance of airflow for determining migratory routes changes as birds gain experience.