Mystacinids have some unusual characteristics compared to other bats. They spend much of the time on the ground, instead of flying, and are unique in having the ability to fold their wings into a leathery membrane when not in use. Another distinctive feature of the group is an additional projection on some of the claws, which may aid in digging or climbing. They are
omnivorous, eating fruit and carrion in addition to ground-dwelling
arthropods. They also eat pollen and nectar, which they are able to collect with their extensible
tongues. They sometimes chew out burrows in rotting wood, but can also roost in rock crevices or the burrows of seabirds. Many old sources refer to the terrestriality of these bats as a trait acquired due to island endemism, assumed to have evolved due to the absence of terrestrial mammals in New Zealand. However,
Icarops, a mainland Australian genus, shows adaptations to terrestriality, suggesting that it evolved prior to the colonisation of New Zealand, in an environment dominated by terrestrial mammals such as
marsupials and
monotremes. Furthermore, the Saint Bathans fossil species co-existed with the
Saint Bathans mammal, suggesting that New Zealand wasn't devoid of land mammals when these bats first arrived. They give birth once each summer, to a single young. They are able to
hibernate during the winter. In 2010 the Department of Conservation discovered a
feral cat that was responsible for killing over 100 short-tailed bats over a seven-day period in a forested area on the southern slope of
Mount Ruapehu. ==References==