Nature Features

"They're feeding like mad," is how Pat Costen described the activity of Guernsey's bat population in the Autumn months. She explained that they do this "to get fat on themselves to hibernate through the winter".

Bats are the only kind of mammal capable of sustained flight and live in most parts of the world in one form or another. The most common species of bat in the Bailiwick of Guernsey are the Common Pipistrelle and the grey long-eared bat both of which are found across Europe.

Both of these species hibernate during the colder months of the year as their food source, flying insects, dries up. However, Pat said that in recent years they are hibernating less "as our winters are getting warmer" and because of this the insects are living longer so the bats are spending more time active.

A pipistrelle in flight

Though bats have no natural predators in Guernsey their traditional position as "creatures of superstition and fear" saw man become their biggest threat.

A clear example of this is the case of the horseshoe bat which in the past existed in the Bailiwick, but has not been recorded since the 1950s as they would often live in houses and, Pat explained, "would be exterminated" when they were found.

In recent years though this perception of the flying animals seems to have changed.

While the grey long-eared bats hibernate in caves they don't hang from the ceiling in the way bats a traditionally depicted. Instead they hide themselves away and can be very hard to locate once they go into hibernation.

Similarly the Pipistrelles don't hibernate in the traditional way but tend to hide wherever they can in small groups and Pat said she had heard reports of them within houses fascia boards and even behind the bark of trees.

As leader of the Guernsey Bat Group, Pat said that they are interested in finding out how many bats there are in Guernsey.

What they do know is that the highest concentration of Pipistrelles is in St Sampsons because of the large quarry now used as a reservoir that attracts moths and flying insects.

(Body image courtesy of the Bat Conservation Trust)