Cats should be kept inside at sunset to stop them killing bats, an expert has said.
Other ways people can help the native bat species is to use blackout blinds, build ponds and eat organically.
There are 18 species of bat found in the UK and they play a vital role in British ecosystems, but some of the nocturnal flying mammals are under threat.
People are increasingly encroaching on their habitat, destroying their food and interfering with their lives.
Beth Gerrard from the Bat Conservation Research Lab at the University of West of England told the Cheltenham Science Festival that there were various things everyone could do to help.
Hours of darkness
She recommended keeping cats inside at night as domesticated felines hunt and kill bats during the hours of darkness.
“If you can’t keep them in at night, if you could keep them in for half an hour before sunset to the hour after sunset, that can really make a big difference,” Ms Gerrard said.
“Bats have a few natural predators, for example, owls and snakes, but domesticated cats aren’t so natural and they actually cause a real issue for bats.”
The Bat Conservation Trust estimates that at least a quarter of a million bats are killed every year by pet cats.
The RSPCA agreed that cats should be kept inside at dusk to reduce the opportunities for hunting birds and other animals.
“Any bird feeders in the garden should also be placed up high out of reach of cats, and to reduce spillage onto the ground to prevent other birds and wild animals feeding there as this can make them more vulnerable to predation,” a spokesman said.
Another simple way to benefit bat numbers in Britain is to stop using pesticides, reduce light pollution and make gardens bat-friendly by enticing insects for them to eat.
Pesticides and herbicides destroy plants which bats rely on for food and sometimes can poison them directly.
“Reducing outside lighting [can also help], so garden lighting but also security lighting. I’m not going to ask you to turn street lights off but you could make [security lights] less bright or just put them on motion sensors so they’re not on all the time,” Ms Gerrard said.
Household lights shining
In a similar vein, she said people should be wary of their household lights shining out into the night through their windows, and consider using blackout blinds.
“You basically want to reduce the light spill going into the outside area which bats are using,” she said.
Other advice for bat enthusiasts includes eating organically to reduce the number of pesticides in use and also to ditch meat and dairy as cattle require lots of land and this is often sourced by invading the habitat of bats.
Other tips Ms Gerrard provided were to add “linear features” to the garden as bats use these to navigate, so a bolt-straight hedgerow could help their migration; grow diverse plants; and build a pond.
“Bats are really important for our ecosystems. Both at local and global scales,” Ms Gerrard said.
“I don’t think people really understand how much impact they actually have on our environment.”
She said they were better pollinators than most insects because they can carry more pollen and take it longer distances.
“We need to make sure that we’re doing everything we can to help alleviate any threats that they’re facing,” Ms Gerrard said.
“Almost one-third of all bats overseas are at risk of extinction. And in the UK we have got four species which are near threatened, four species that are at risk and two species that are classed as near threatened.
“Bat populations massively decreased last century, but I think most bat species populations are now going up.”