Bats were preying on migratory birds in flight—the first ever visual observation and recording of aerial predation in the world

by the University of Tokyo
July 23, 2026

A research group led by Associate Professor Dai Fukui of the Graduate School of Agricultural and Life Sciences, the University of Tokyo, and Keimei Fujioka, a special support staff member for agricultural science at the same graduate school and a commissioned researcher at the Acoustic Navigation Research Center, Doshisha University, has visually revealed the behavior of bats preying on birds in mid-air.

Bats are the second most numerous group of mammals after rodents, and have diverse diets ranging from insects and plants to vertebrates. Among them, a small number of species have been identified that prey on terrestrial vertebrates and birds, and in particular, three species that prey on birds in temperate regions usually feed on insects, but fecal DNA analysis has shown that small migratory birds become their main food source at certain times. In Japan, it is known that the relatively large Japanese bat (wingspan 40 cm, weight 40 g) preys on small birds during the autumn bird migration season.

However, how bats catch relatively large prey such as birds has long been unknown, with two main theories: one suggesting they attack birds resting in their roosts, and the other suggesting they capture birds in flight. Recent GPS tracking, behavioral experiments, and sensor-based research now support the possibility that bats descend from above to capture birds in flight. However, the evidence to date has been based on acoustic and experimental data, and there have been no reported instances of visual observation of bats actually preying on birds in flight.

Keep reading (in Japanese): https://www.a.u-tokyo.ac.jp/topics/topics_20260723-1.html

Read the Ecology paper: https://esajournals.onlinelibrary.wiley.com/doi/10.1002/ecy.70459