Wildlife & Nature to See in June : Bats
Wildlife to See in June : Bats
The UK is home to 17 species of bat, the most common of these being the Common Pipistrelle (Pipistrellus pipistrellus). The common pipistrelle has dark chestnut-coloured fur, a short, dark muzzle, and small triangular ears with a rounded tip. They are the smallest of our bats (and the smallest within Europe), weighing between 4-8g.
The reason for the common nature of the pipistrelle is its ability to live in a variety of habitats, such as farmland, woodland, hedgerows and lakes, not to mention being the most urban-dwelling of our bat species. It was suggested in a study in 1998 by Oakeley and Jones, that mother pipistrelles use hedgerows as a linear feature for navigating back to their nests. Therefore, like many British species, the common pipistrelle would benefit from the planting of more hedgerows, not only for this, but for ease of finding prey. They feed on aquatic insects, found above water-sources, and a variety of moths and gnats. A single pipistrelle may consume 3, 000 insects in one night.
Like celebrities and the wealthy, common pipistrelles have both summer and winter abodes. They hibernate between November and April in buildings or trees, often inhabiting churches or old barns. Besides the loss of hedgerows, a further reason for a decline in bat populations is the removal of old and derelict buildings which are vital for their winter survival. During the summer, bats change roost sites to trees or bat nesting boxes, to mate and raise their young.
In June the first pipistrelle babies will be born, usually one per mother, in a nursery roost of between 300 and 1,000 individuals, so now is a good time to see frantic mothers gathering enough food for milk production. During this period males live in smaller colonies. Bats usually emerge to feed about 20 minutes after sunset, and pipistrelles can be identified through their somewhat jerky and fast flight pattern, often following the same route every night. If you are fortunate enough to have access to a bat detector, you can identify pipistrelles by picking up their echolocation calls, which they use to bounce sound off potential prey to gather information about its whereabouts. Details about their call frequencies can be seen on this website: http://www.bio.bris.ac.uk/research/bats/britishbats/batpages/commonpipi.htm
The common pipistrelle is a protected species, although it is preyed upon by the weasel and domestic cats, and is declining in numbers due to changing habitats. However, studies have shown that an increase in organic farms could improve their numbers, due to a lack of harmful agricultural chemicals.
I have spent half the morning downloading bat calls onto my iPod from the Bat Conservation Trust’s website.
Some of them are difficult to distinguish, but others are decidedly funky! Listen to the Leisler’s bat in particular, which I am currently trying to persuade my step-brother to use as part of a music project. The Common Pipistrelle itself sounds to me like hands being tapped onto a leg.