Helping Cavity Nesting Birds

What’s at Stake

Several birds that breed in San Francisco require cavities in which to put their nests.Collectively known as “secondary cavity obligates”, these birds rely on woodpeckers or natural phenomenon to create the holes are hollows they need. While there are several common species of cavity nesters, a shortage of appropriate nesting cavities and the woodpeckers that create them can be a limiting factor for the survival of certain nesting birds. The cavity nesters that we are targeting and are of local conservation interest include wood duck, American kestrel, western screech-owl, Bewick’s wren and violate-green swallow. Other, more common native species that are also expected to use the boxes include chestnut-backed chickadee, tree swallow, winter wren and pygmy nuthatch.

Taking Action

Working with the Golden Gate Chapter of the Audubon Society we have enhanced nesting opportunities of native cavity nesting birds on the Zoo’s grounds. By erecting various sizes of nesting boxes though out the Zoo, we have effectively supplemented the breeding opportunities for cavity nesting birds.

The San Francisco Zoological Society is the steward of one of the largest parks in San Francisco. The varied landscape and wetlands within the park provide habitat for a rich variety of native wildlife, especially birds. The grounds are also an important piece of a larger mosaic of wildlife habitat in southwestern San Francisco that includes Lake Merced, Ocean Beach, and Fort Funston.