In praise of warblers

George Walter

Jill Severn | The JOLT News

These tiny insect-eating warblers are perhaps the most amazing of all our Thurston County breeding birds. They weigh less than one-half ounce yet manage to migrate hundreds and sometimes thousands of miles from their wintering territory, arriving here by mid-May to claim a breeding territory.

Imagine all those tiny wings flying from Central America to northern Alaska, and then back again! 

The warblers’ breeding achievements are also impressive. Most warblers build a rough bulky outer nest, maybe 5 inches across, made of leaves, bark, and other materials. Then, in the center of this, the female will construct a small (2-inch) cup-like nest lined with hair, feathers, and fine plant materials. Three to four eggs per nest are normal.  

Some warbler species nest close to the ground, others in bushes and small trees, and still others in tall conifers. Occupying different habitat niches means not competing for prey (insects and larvae primarily). And those babies need lots of food. They grow from tiny naked hatchlings weighing one-20th of an ounce to a fledgling in about 14 days — that's a lot of insects! 

We have nine species of warblers breeding in this county, which seems impressive until one considers that there are 53 warbler species across North America. They are all small and virtually all manage those long spring migrations to reach their summer homes. 

When you’re looking for warblers, in addition to appearance, pay attention to the bird’s level of activity. They are constantly on the move, looking here and there for their next meal.  

All our warblers sing an impressive territorial song (they’re warblers, after all). Some, like the yellow warbler, sing from an exposed perch and are easily seen; others like to hide in the undergrowth. But they all respond to humans’ “pishing,” that generalized alarm note that provokes many small birds to come closer.  

Orange-crowned Warbler

Photo by Liam Hutcheson

Orange-crowned warbler males are singing right now — I heard one this morning. They are active birds and like open brushy areas and edges, especially near water. The males’ song is a pleasing light trilling, usually rising slightly then falling. You know the lament of birders about so many species of bring “little brown birds”  Well, these warblers are little green birds.  

Wilson's Warbler

Photo by Liam Hutcheson

Another warbler using similar brushy habitat is the Wilson’s warbler. This is also a little green bird, but with a bright yellow breast and belly. The male, the one you’re most likely to see, has a distinctive black cap which may predict its new common name (coming soon from the American Ornithological Union). The males sing a song of quick sweet-sounding chips.  

A MacGillivray warbler.

Liam Hutcheson | For The JOLT News

You may encounter a third species, the MacGillivray’s warbler, in brushy areas, although they prefer thickets in forested areas. This is another little greenish bird, but this one has a distinctive gray hood. Its song is short, and made up of burry sounding notes, usually written as "churry, churry, cheery, cheery." This species will sometimes get a new common name as well, but since hooded warbler is already taken the new name is not so easily predicted. 

Townsend’s warbler (yet another species soon to be renamed) is a bird that prefers taller conifers. Their nests are usually 30-plus feet above ground. They forage in the forest canopy, eating whatever insect food they encounter. Your best chance of seeing them is to first hear their song, a short series of soft whistle notes, then use “pishing” to attract them down out of the treetops. Some individuals stay nearby in the winter and Olympia usually has a few on each Christmas Bird Count.  

Black-throated Gray Warbler

Photo by Liam Hutcheson

A final warbler in the forest’s upper stories is the black-throated gray warbler. These birds are distinctive, with a gray back and black and white sides and face. They also have a bright yellow spot behind the bill that is easily seen. They are more likely to be lower down in the forest trees and often forage in edge habitat.  

Of the four county warbler species not discussed here, common yellowthroat, yellow warbler, yellow-rumped warbler and hermit warbler, only the latter is rare and difficult to locate. So, here’s an interesting challenge: try to find as many of the nine Thurston County warblers as you can during the current breeding season.  

First, check your bird book to remind yourself of what these nine species look like. They all have thin insect catching bills, are very active and usually quite colorful; often you will hear the male singing before you see the bird. And, of course, use the faithful Merlin app to confirm the song’s identification.  

George Walter is environmental program manager at the Nisqually Indian Tribe’s natural resources department; he also has a 45+ year interest in bird watching. He may be reached at george@theJOLTnews.com 

Photos for this column are provided by Liam Hutcheson, a 17-year-old Olympia area birder and avid photographer. 

Editor's note: This column has been updated.