Olive-sided Flycatcher

A demand for beer—and conservation

By Pat Leonard

Olive-sided Flycatcher by Brian L. Sullivan

If any bird can be said to have a "zest for life," it could well be the Olive-sided Flycatcher. This feisty bundle of feathers lives up to its name as a "tyrant" flycatcher, aggressively defending its territory by bill-snapping and dive-bombing intruders, snatching bugs in midair and, day or night, delivering its trademark song: "Quick, THREE BEERS!"

Described in Birds of North America Online as "bull-headed, short-tailed, and stout-billed," this denizen of the Rockies and Canada's northern boreal forest is clad in dark plumage along its head and back. Its white throat, breast, and belly, flanked by dark patches, create an unbuttoned "vest" fashion statement.

Unlike most other North American flycatchers, the olive-sided relies exclusively on aerial "hawking" to feed. From a treetop vantage point, it darts forth to scoop up bees, wasps, flies, moths, grasshoppers, and dragonflies. It makes one of the longest migratory journeys of any North American flycatcher, wintering primarily in Panama and the Andes of South America.

Map by Cornell Lab of Ornithology. Range data by NatureServe

Like many forest birds, the Olive-sided Flycatcher is most threatened by the loss of habitat at both ends of its migratory route—open conifer and mixed woodland. In a large portion of its range, numbers have dropped by as much as 50 percent over the last 30 years to an estimated population of 1.2 million.

Although occasionally still seen in the Appalachian Mountains, the Olive-sided Flycatcher has become increasingly rare. In places where an effort has been made to plant the trees most favored by the olive-sided, populations have rebounded, particularly in California, the Canadian Maritime provinces, and in parts of Quebec and Vermont.

The Olive-sided Flycatcher is considered a "Species of Concern" by the U.S. Fish & Wildlife Service and is listed as an endangered or sensitive species in half a dozen regions and states. It is also a priority species for conservation on the Partners in Flight National Watch List.

Getting a firmer grasp on distribution and numbers via the Lab's new Priority Migrant Monitoring Project is an important step toward learning what conservation steps are needed to keep this frisky flycatcher bellowing for beer. For more about the priority migrant project, see the article about the new Focal Species Monitoring Program in this issue.

For permission to reprint all or part of this article, please contact Laura Erickson, editor, Cornell Lab of Ornithology, 159 Sapsucker Woods Rd., Ithaca, NY, 14850. Phone: (607) 254-1114. email: lle24@cornell.edu