May 31, 2017

Snakes hunt in packs and hang upside down to catch bats

We've all been waiting for Snakes on a Plane 2 (haven't we?), but the movie just needed a new angle. New research may have delivered it: snakes attacking in packs.

Snakes on a Plane, Indiana Jones and Anaconda (sorry, Indy, you're not in great company there) all reminded us how scary snakes can be-- and that was before we knew that some hunt as a team.

Cuban boas, a University of Tennessee, Knoxville scientist has found, work in groups to make hunting more efficient.

A fence of snakes

The idea may be creepy to some, but it also reveals a lot about how intelligent snakes are.

"Coordinated hunting requires higher behavioral complexity because each animal has to take other hunters' actions into account," said Vladimir Dinets, the study author and an Assistant Research Professor in the university's Department of Psychology.

Although increased food intake is likely the main reason for behavior, it's also possible that there is a social function.

Snakes have been observed to hunt together previously, but the amount of coordination was questionable, and Dinets' research is the first scientific recording of such behavior (the BBC's Planet Earth II being a famous previous example).

The new research showed how individual snakes take into account the location of others.

The snakes Dinets studied were hunting fruit bats in Cuba. At dawn and dusk, they positioned themselves around the mouth of the cave in such a way as to increase the chances of catching prey.

"Snakes arriving to the hunting area were significantly more likely to position themselves in the part of the passage where other snakes were already present, forming a 'fence' across the passage and thus more effectively blocking the flight path of the prey, significantly increasing hunting efficiency," an extract from the study explained.

Hanging like bats

This particular species of snake can reach 2 meters (6 ft) in length, which makes the fact that they hang upside down from the roofs of caves even more awe inspiring.

"After sunset and before dawn, some of the boas entered the passage that connected the roosting chamber with the entrance chamber, and hunted by suspending themselves from the ceiling and grabbing passing bats,"Dinets said.

He observed that the positions taken up by the snakes lowered the chances of bats getting out of the cave. Brilliantly, those hanging positions also meant they behaved like the bats they were trying to catch.


Image credit: Boris Smokrovic/Unsplash