Bats Only Roost Among Friends

It seems that this Halloween, bats are only hanging out with their friends, after a new study showed that these mammals will roost solely with their usual social groups.

Bats find shelter in caves, crevices, tree cavities and buildings, according to Defenders of Wildlife, and in these settings different social groups will roost separately. It seems humans aren't the only ones with social cliques.

Described in the journal PLOS ONE, this can be seen in two different, but closely-related species living in separate, though adjacent, parts of woodland. Natterer's bat (Myotis nattereri) forms mixed-sex social groups while a second species, the Daubenton's bat (Myotis daubentonii) has largely separate male and female groups.

"When the first results came through it was a real eureka moment, I hadn't expected to see so many separate social groups in the woodland," Dr. Tom August from the Centre for Ecology & Hydrology, who conducted the study, said in a statement.

Over a five-year period, researchers studied nearly 1,500 bats fitted with small aluminium arm bands, and tagged some with tiny lightweight radio-transmitters for tracking purposes. The results showed that these flying rats with wings changed roost sites quite frequently - about once every two days. And when "moving house," they would most certainly avoid nesting near bats of a different social group - despite living within the same woodland.

Not only does this shed light on the bats' social structure, but it will also help scientists better protect populations in the wild.

"This work has really important practical implications for bat conservation. We now realize that although social groups of woodland bats 'move house' every few days, they remain within a very small geographical range. This means that even quite small-scale tree felling may destroy all the roosts potentially available to a group," explained lead researcher Dr. Fiona Mathews, from the University of Exeter.

I guess it's safe to say that on Halloween, bats with be celebrating simply among friends.