The Egyptian fruit bat (Rousettus aegyptiacus) uses its keen senses to collect information from its surroundings as part of its decision-making process. In an urban environment, foraging-related decisions, like what to eat, where to eat, how long to stay, or when to leave a food patch, become even more complex due to the rich and varied food sources available in the city and in private gardens. 

A study being carried out by Lee Harten and Michal Handal, from Dr Yossi Yovel's research lab in the Zoology Department, examines the use of bats' individual knowledge in foraging-related decision-making by the Egyptian fruit bat. Why do bats prefer a specific kind of tree? Why does a bat choose to visit regularly a specific tree? Why does it stop visiting it? This research is attempting to answer these and others questions. 

Yossi Yovel's lab has established a bat colony in the Zoological Garden that simulates a natural colony, in which the bats sleep during the day and are free to fly out to forage every night. The bats are on a 24/7 surveillance regime. Tiny GPSs attached to their backs allow the researchers to follow their flight paths and to identify the food patches that the bats visited during the night.
The Botanical Garden is a preferred foraging site for the bats, thanks to the large variety of fruit trees on which they feed. During the current season the colony of bats is feeding mainly off the fruit of the Indian laurel (Ficus microcarpa). For example, the bat named Fin visits the Botanical Garden every night and feeds on the fruit of the false sycamore fig (Ficus sycomorus) and on the sweet fruit of the Indian mango (Mangifera Indica) that have ripened recently.

The Ficus avenue, Photo: Gavri Sion

The Ficus avenue, Photo: Gavri Sion

An Egyptian fruit bat with a GPS, Photo: Sasha Danylovich

An Egyptian fruit bat with a GPS, Photo: Sasha Danylovich

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