Bird Bio: Vaux’s Swift

Bird Bio: Vaux’s Swift
By Melissa Molzahn, KBO Education Specialist (AmeriCorps)

The Vaux’s Swift is often seen flying swiftly overhead, in one direction, then another, at top speed. This small and agile bird rarely perches unless it is nesting or roosting. It can be observed busily hawking all sorts of tiny insects, especially when feeding young.

Generally a summer resident in Oregon, Vaux’s Swifts arrive in late April or early May. They can be found breeding from Canada through California and begin to take off to their wintering grounds in mid-September, travelling as far south as Honduras. Vaux’s Swifts prefer old-growth forest habitat and rely on large-diameter hollow snags for nesting and roosting. Like their eastern cousin, the Chimney Swift, the Vaux’s Swift has been known to utilize brick chimneys in lieu of trees for roosting and nesting.

During migration, these birds stop over at various locations in Oregon and northern California where they roost in groups of over 10,000 birds for several weeks, often in chimneys. Each night they swirl into the chimneys at sunset. KBO will highlight such a location—Eden Valley Farms—at
its Wings and Wine event (see page 1).

Vaux’s Swift populations declined significantly in the 1980s and are believed to be in continued decline. Since oldgrowth forest habitat with hollow snags is so important for this species, forest management practices retaining snags benefit this species. Nest boxes (3.5 m tall and 30 cm square) placed in trees 10-15 m above the ground provide a shortterm alternative to large-diameter hollow trees. As their main source of food is aerial insects, limited pesticide spraying in known roosting locations can ensure that their food supply will not be depleted, especially during the breeding season. Given that large flocks of birds now use chimneys as their migratory roosting sites, maintaining open brick chimneys will also aid the conservation of Vaux’s Swifts.

Learn more about the conservation of Vaux’s Swifts at KBO’s Wings and Wine celebration!

This article appears in the Summer 2008 KBO newsletter.

References:

Birds of Oregon, first edition 2003, edited by D.B. Marshall, M.G. Hunter, & A.L. Contreras; The Birds of North America, first edition 2005, edited by Dr. Alan Poole and Dr. Frank Gill.

Vaux’s Swift Photo: (c) Jim Livaudais