By Gail Cleveland
High up near the tip top of a fir tree in Glacier Park, I can hear the distinctive song of one of my favorite Northwest Montana warblers. If I am lucky, he may come out and sing from the top of the tree, but I am not getting my hopes up. I also didn’t bring my neck brace, which would definitely be handy when looking for these tree top singers. When he does come into view, this medium-sized wood-warbler is strikingly arrayed with an olive green back, a black throat, a large yellow eye patch with a black stripe, a yellow breast with white underbelly and two white wing bars, making this Townsend’s Warbler arguably among the most beautiful birds of western North America.
The Townsend’s is one of five North American black-throated warblers. The Black-throated Green is primarily an eastern bird, which also nests north of us in Alberta and Saskatchewan. The Hermit is primarily a west coast bird, along with the Black-throated Gray which is also a western interior bird. The rarest of these black-throats is the Golden-cheeked, which can be found only in a small part of central Texas.
The Townsend’s breeding range is west of the Rocky Mountains and includes parts of Alaska south through much of British Columbia to the Olympic Peninsula in Washington and to the mountains of western Montana, the Idaho panhandle and northeast Oregon. The habitats of the Hermit and Townsend’s Warbler overlap. Researchers believe that Townsend’s are displacing Hermit Warblers in these zones because they are more aggressive at attracting females and have larger clutches of eggs. There have been examples of hybridization of the two species as well.
The winter range for our Townsend’s Warbler extends from southeast Arizona and southwestern Texas to extensive regions of Mexico all the way to Costa Rica. The West Coast Townsend’s actually winters on the Pacific coast from British Columbia to southern California.
The black-throated warblers have songs that are distinctive from other warblers and similar to each other. I call them the “zoo zee” warblers. For me, they are the easiest warblers to identify. Whether I have been in Glacier Park or on the West Coast, in a Utah desert or lucky enough to hear a Golden-Cheeked in Central Texas, their wheezy, buzzy notes make me stop in my tracks and say “a black-throated warbler.” My general moniker for these lovelies is “zee zee zoo zee.” Although each has a different song, this general pattern will identify a black-throated warbler.
I have never seen a Townsend’s nest, as it is typically high up in the canopy and well concealed by foliage. It is a bulky cap of grass, moss, bark strips, and twigs, lined with hair, feathers and moss. The female, a duller version of the male without a black throat but still with the distinctive yellow eye patch, incubates 3 to 5 eggs for 11 to 14 days. Both male and female feed the young, which leave the nest about 10 days after hatching.
They feed primarily on insects on their breeding grounds, although berries and some nectar round out their winter diet in warm climates.
Our Townsend’s arrive here in mid-May and often stopover in the valley if the high country is still wintery. They can sometimes be seen feeding in lower branches of the valley conifers before they ascend to their breeding grounds. In June and early July when they are still singing, two good spots to hear and/or see them are on the Big Mountain or in Glacier National Park.