Gardening for Bats

Habitat gardening is more than sunshine, pretty flowers, and butterflies. When the dark of the night arrives, watch out — ferocious nocturnal hunters are on patrol! Unlike the blood-sucking vampires or shrieking swarms you might see in the movies, most bats are shy little creatures that feast on insects. As the only flying mammals on earth, they play a unique ecological role that shares as much from burrowing critters like mice, shrews, and squirrels as avians overhead.

Meet Your Neighbors: Portland’s Bats

If you poke through every nook and cranny, there are fifteen native species of bat in Oregon. Most of the bats you’ll see in the Portland Metro are either ‘big brown bats’ or ‘little brown bats’ (real creative names, right?) Further afield in areas bordering waterways and mature forests, you might also meet the enigmatic hoary bat and silver-haired bat.

Big Brown Bat - With a 13 - 14 in wingspan, the graceful big brown bat is one of North America’s largest bats and the most common visitor to bat houses.
Little Brown Bat - Much smaller than its cousin with a wingspan of just 9 - 10in, the little brown bat is another common garden visitor that flits around in distinctively rapid, erratic patterns.
Hoary Bat - If you hear an audible ‘chattering’ overhead, you might be in the company of the solitary hoary bat. They’re less common in urban areas and migrate south to warmer climates in the winter, so they’re an especially impressive sight with a silvery pelt and a wingspan of up to 15 inches.
Silver Haired Bat - Found gliding along waterways or beneath old-growth forest canopy, this tiny bat is a ferocious hunter despite its wingspan of 11 - 12in. They form maternal colonies in the snags of mature forests.

Big Brown Bat — Eptesicus fuscus

With a 13 - 14 in wingspan, the graceful big brown bat is one of North America’s largest bats and the most common visitor to bat houses.

Little Brown Bat — Myotis lucifugus

Much smaller than its cousin with a wingspan of just 9 - 10in, the little brown bat is another common garden visitor that flits around in distinctively rapid, erratic patterns.

Hoary Bat — Lasiurus cinereus

If you hear an audible ‘chattering’ overhead, you might be in the company of the solitary hoary bat. They’re less common in urban areas and migrate south to warmer climates in the winter, so they’re an especially impressive sight with a silvery pelt and a wingspan of up to 15 inches.

Silver-Haired Bat — Lasionycteris noctivagans

Found gliding along waterways or beneath old-growth forest canopy, this tiny bat is a ferocious hunter despite its wingspan of 11 - 12in. They form maternal colonies in the snags of mature forests.

Photos by Michael Durham via Oregon Department of Fish & Wildlife

Nature's Pest Patrol

Have bats really earned their bad reputation? Our local bats are gentle creatures and, though they’ve long been villainized as carriers of disease, less than 3% of bats carry rabies. Healthy bat populations can actually help reduce the risk of animal-borne pathogens — each bat can consume up to 1000 mosquitoes a night! Their appetite for insects is credited for saving billions of dollars in agricultural crop loss and pesticide use. In your yard or neighborhood, that means bats are working hard as the ultimate organic pest control.

Bat-ier Homes and Gardens

When you garden for butterflies, you can research the host plants their caterpillars rely upon. When you plant for songbirds, you can offer a feast of berries and seeds throughout the seasons. Gardening for bats is a little different because you’re not looking for specific plants — you’re creating an environment that provides shelter and supports a diverse population of insects to eat.

Plants for Bats

‘Bat gardening’ flows beautifully with other types of habitat gardening. If you’re working to support pollinators and other insects, you’re already creating bat habitat. As night-time predators, bats love to feast on moths, so planting white or pale flowers creates a buffet for these nocturnal neighbors. Since most bats in the Pacific Northwest evolved in forest habitats, large trees (especially native conifers) provide the sense of safety that they need to traverse the complex landscape below. For our most common urban bats, prime habitat conditions are often the same traits as a healthy garden ecosystem.

Landscape Best Practices for Bats

Welcoming bats into your landscape is about more than plant choice.

Skip The Insecticides — In a vacuum, insecticides are intended to reduce pests. Viewed in the lens of a broader ecosystem, though, even the most undesirable ‘pests’ are a food source for other creatures. Bats and birds both rely on large quantities of insects to keep up their energy and feed their young.

Keep Cats Indoors — Our beloved pet cats are talented non-native predators who can do serious damage to wildlife populations. While humans’ rare interactions with bats limit disease exposure, cats can bring a bat with rabies or another infectious illness directly to your doorstep. The best way for cats and wildlife to coexist is keeping Fluffy safely indoors.

Keep The Lights Down — Nocturnal animals like bats have evolved to explore a dark landscape, lit only by the moon and stars. For human safety, our cities are filled with lights that completely change the geography for a nighttime hunter. We can minimize impacts to bats and other creatures by limiting our light pollution i.e. closing our blinds at night, implementing timers on porch and walkway lights, and choosing outdoor lights that point downwards rather than up at the sky.

Bat Houses

When dusk arrives and bats flutter through the air like tiny gymnasts, it’s a charming sight to behold. In urban areas, creating bat habitat is mostly about attracting their food and leaving them to their nightly hunting routine. However, if you’re lucky enough to have the space for a bat house and you’re up to the task, you could actually install a home for an entire colony of bats. Most bat species are highly social, so they cluster together for comfort, safety, and warmth. Providing a nesting box with the right conditions can attract these flying critters to take up residence on your property — and they’ll even pay the rent in mosquito control and nutrient-rich guano. It can be challenging to properly site and set up a bat house, so we’ll point you to Bat Conservation International for more information.