Bird species in the diet of the birdlike noctule bat, Nyctalus aviator, in Japan.

We investigate the birds in the diet of the birdlike noctule (Nyctalus
aviator) through DNA amplification from feather remains found in fecal
pellets. Our goal was to confirm that N. aviator preys on nocturnally
migratory species, as does its European relative N. lasiopterus, and to
gain insights into this hunting strategy (e.g. on the wing vs. from
cavity-nest). The diversity and the characteristics of the birds found in
the feces remains indicate that in Japan N. aviator employs a similar
hunting strategy on songbirds as N. lasiopterus in Iberia.  Both
noctules are primarily generalist insectivores that prey on 5-25 g body
mass songbirds seasonally during their migration and probably hunt them at
high altitude. Accordingly, predation on birds seems to be a strategy that
appears in distant points across the Palearctic and is not the result of
local specialization. We hypothesize that the bird hunting behavior
appeared during evolution as a trophic jump from a pre-existing hunting
behavior on the many insects that carry out seasonal nocturnal migrations
in temperate zones at high-altitude.