How to make your garden bat friendly

The leaves are finally falling, and autumn showers have arrived in B.C. as a long dry season comes to an end. 

B.C. residents will be heading into their yards to clean up the debris, but advocates are urging people to think about how their yards and gardens could support bats over the winter and into the spring.

"Bats are hugely beneficial to our ecosystems," Danielle Buckle, the southern Vancouver Island bat co-ordinator for the B.C. Community Bat Program, told All Points West guest host Rohit Joseph. 

"They're really important nutrient cyclers. They eat a lot of really negative insects like agricultural pests and mosquitoes ... In other parts of the world, [they] pollinate flowers, spread seeds and other nutrients, so they're really important to our ecosystem."

About half of the bat species in B.C. are classified as at risk, meaning they're vulnerable and could become extirpated. 

Buckle sat down with CBC's All Points West to talk about best practices for creating a bat-friendly space in your yard.

Plant native plants

Buckle says planting native trees, shrubs and flowers in your yard or garden helps increase biodiversity in the space, including the insects on which bats feed. 

Additionally, removing invasive plants, such as Scotch broom, Himalayan blackberry and common burdock, will help bats thrive. 

"Bats can get caught in burdock," Buckle said, adding that it could lead to injury or even death. 

"Invasive plants are really negative for our ecosystem and decrease biodiversity, so it's really important to remove them."

Make space for roosting

Bats roost in caves, some trees and in bat houses, so ensure there is some space for them to settle in. 

According to Bat Conservation International (BCI), dead trees, in particular, are a "gold mine" for bats, providing a place to roost and a place for insects, bats' dinner, to thrive. 

"If you can leave dead trees up safely, we highly recommend this practice," the organization says in its Guide to Gardening for bats. 

Buckle said people often kick bats out of barns or attics, leaving them nowhere to go.

"By building bat houses and putting them up, you can help create more habitat for bats."

Instructions on building a bat house can be found online, or you can purchase a prefabricated bat house.

Food and water

Plants with flowers that stay open through the evening attract native insects, which gives bats easy access to food during their nighttime hunting. Insects are especially attracted to light-coloured or white flowers, BCI says.

BCI also says bats love moths, so trees such as hickory, plum or birch, which attract moths, will help provide a hearty food source.

While a bird bath might seem like an easy way to offer up water, BCI says they need two to three metres of water to drink because they drink while flying. The organization suggests a pond or water trough instead. 

No cats, light

Cats kill millions of birds each year, and they aren't particularly discerning when it comes to bats. 

Keeping cats indoors, away from bats, birds and other creatures helps keeps them safe. 

Additionally, light pollution can be harmful to bat behaviour, affecting the way they hunt. BCI advises keeping the lights off in the yard or garden where they're roosting and hunting.

Leave the leaves alone

Buckle says that though it may be tempting to tidy up the yard by raking leaves and disposing of them, they should be left alone. 

Insects, including those that bats feed on, sometimes winter in dead leaves. Without those bugs, the bats won't have anything to eat come spring.