The population of an endangered Australian bat suddenly dropped by up to 16%. No one knows why

Exclusive: Scientists say about 5,000 fewer southern bent-wing bats have been recorded at a key maternity site for the species

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A sudden decline in critically endangered bats is troubling experts, who recorded about 5,000 fewer southern bent-wing bats than usual at Naracoorte’s “bat cave” this summer.

These tiny russet-toned microbats roost in caves and forage for insects over long distances across south-west Victoria and south-east South Australia.