Photo: Carolina Chickadee, Douglas Tallamy
The Audubon at Home program helps homeowners create wildlife habitat in their own yards, with the aim of attracting and supporting beneficial species who breed and live in our area. We call these species Sanctuary Species. If a yard attracts 10 Sanctuary Species who nest, breed, forage, shelter, or use the yard in any way, then it’s a Wildlife Sanctuary—our motto is, “Let the animals decide.”
One such Sanctuary Species is the Carolina Chickadee (Poecile carolinensis) that common, cheery visitor to backyard bird feeders. Chickadees are year-round residents and this small bird must contend with cold and potential heat loss. About half survive the winter. Homeowners can do plenty to bring chickadees to their yards and help them survive by providing a bird feeder. Hang feeders a short distance (maybe 6 to 10 feet) from trees and shrubs so birds can quickly seek cover when predators like hawks appear. Birds also need to be able to spot predators approaching on the ground, such as outdoor cats. Chickadees are cavity-nester; they can excavate nests with their little bill, although they’re not as good at it as woodpeckers. So, preserve trees (dead or alive) with cavities to provide roosting and nesting sites. Chickadees will use nest boxes, too.
Carolina Chickadee, Douglas Tallamy
More than anything, though, chickadees need a yard full of native plants. How can that be? What do chickadees have to do with native plants?
Well, native plants are required to support native insects such as caterpillars, which chickadees depend on for over half their diet. Caterpillars and other insects are especially critical when chickadees are raising young. Because the nestlings need protein to grow, they eat a diet almost exclusively of insects. Most native insects, such as caterpillars, are specialists: they eat only the host plants with which they co-evolved. Without native plants, there are fewer native insects, and without insects, birds cannot thrive, no matter how many bird feeders are available to them.
An ingenious study conducted by Douglas Tallamy and his colleagues in yards right here in the DC area confirms the effect. Scientists measured the amount of native plant material in each yard, then they observed whether chickadees nested in it and how successful their nesting efforts were. They found that yards in which less than 70% of the plant material (trees, shrubs) was native could not support insects and did not sustain chickadee families. Chickadees were less likely to nest in such yards and those that did had less reproductive success. Yards with less than 70% native plants were “food deserts” lacking sufficient caterpillars to feed nestlings, leading to declines in chickadee populations. You can read the study here.
Fill your yard with native trees and shrubs and you will attract more chickadees (as well as other wildlife) and the birds will fledge more young.
There are 42 Audubon at Home Sanctuary Species including birds, amphibians, reptiles, insects, and mammals, listed here. Click on the thumbnail picture to learn more about them and their habitat needs.
And, if you’re a photographer who enjoys photographing wildlife, please consider submitting your photos of any of the Sanctuary Species. We are updating our website, and need more and better photos of them in their natural habitats. Send your photos to aah@audubonva.org with Sanctuary Species Photographs in the subject line. We credit all photos that we use.