This weekend, the Bat Conservation Trust is encouraging us to join in celebrating International Bat Night on the night of 26th-27th August. With the recent warmer weather, and a Bank Holiday weekend, it's the perfect time to get outside and enjoy the wonderful world of bats! They typically begin hibernating from October through to March or April, so the summer months are the best time to see them flying. The first half hour after sunset is when you’re most likely to see them.
There are 18 species of UK bats, accounting for about a sixth of the UK's 107 mammal species. The largest is the noctule bat, still smaller than the palm of your hand! The noctule is usually the first bat to appear the evening, sometimes even before sunset. They fly unusually high for bats, high above the tree canopy, and can be mistaken for swifts on the wing.
There are three species of Britain's smallest bat, common, soprano and Nathusius’ pipistrelle. They can be found roosting and foraging in many different locations and habitats. Our most common bat species, common pipistrelles live in colonies of 1,000 or more. They appear fast and jerky in flight as they dodge about pursuing small insects which the bats catch and eat on the wing. A single pipistrelle can consume up to 3,000 insects in one night! Common pipistrelles weigh around 5 grams, which is the same as a 5p piece.
Like so many species, bats have suffered declining numbers in recent decades. This may be due to changing agricultural practices, and also to modern construction and insulation methods reducing valuable roosting sites. Falling insect numbers have also had a dramatic effect on bats.
But all is not lost. According to the Bat Conservation Trust, common pipistrelle populations have started showing signs of recovery in recent years. And there is a lot we can do in our own gardens to encourage bats to thrive. A fun (though slightly advanced!) activity is to build your own bat box. Or of course you can buy one or two ready made ones. Research has shown that bats are more likely to roost if you have several boxes up near each other. Once you've put them up don’t disturb them, as bats are protected by law.
Making a bat box for the garden
Heather Stuckey (rspb-images)
Anything we can do to increase insect numbers in our gardens will make it more likely that bats will come feeding in the area. Grow plants that flower early and late in the season to support as many insects as you possibly can. Evening-scented flowers, such as honeysuckle, attract night-flying insects like moths - a favourite food of bats. If you have space, trees and hedges can provide both navigational aids and potential roosting sites for bats. And installing a pond in your garden can also really help them as even a small pond boosts insect biodiversity for species loved by bats, such as hoverflies, mosquitoes and midges.
So why not get out in your garden this weekend and see if you can spot any bats overhead!