By Bryan Stevens
The warbler parade that begins each autumn with such brightly colored migrants as Blackburnian warbler, black-throated blue warbler and magnolia warbler usually ends with some of the less vibrant members of this family of New World birds.
On a recent bird walk at Sycamore Shoals State Historic Park in Elizabethton, Tennessee, I helped locate a flock of 13 palm warblers and a single yellow-rumped warbler. These two warblers, which look rather brownish and nondescript in the fall, pass through the region later than most other migrating warblers. In fact, the yellow-rumped warbler is one of the few warblers that routinely spends the winter months in the region.
The yellow-rumped warbler has a most suitable name thanks to the yellow patch of feathers on the bird’s rump. The resemblance of the patch to a pat of butter is uncanny enough to have encouraged birders to nickname this often abundant winter warbler the “butter butt.”
The palm warbler’s name is, at best, a misnomer. Throughout most of its life, the palm warbler doesn’t even encounter palm trees. Johann Friedrich Gmelin, a German naturalist who lived from 1748 to 1804, saddled the palm warbler with its inappropriate name. Gmelin based his naming of the bird based on the fact that a specimen had been collected on Hispaniola, an island in the Caribbean with an abundance of palm trees.
Gmelin published several textbooks in the fields of chemistry, pharmaceutical science, mineralogy, and botany. He also had a hand in publishing a catalog of scientific names for various species, including some birds that had until that point never been given a species classification. Thanks to his efforts, a warbler has forever been linked with a type of tree that is, at best, entirely incidental to the bird’s life cycle.
Palm warblers do seek out warmer domains during the winter months, including the islands of the Caribbean. Some of them do not even migrate that far, choosing to remain along the Gulf and Atlantic coastlines of the southern United States. On occasion, individual palm warblers choose to remain in northeast Tennessee, southwest Virginia or western North Carolina during the winter months.
Every spring, however, palm warblers make a long migration flight north. This warbler is one of the northernmost breeding warblers, spending the summer months in the boreal forests of Canada. They build their nests in the thickets surrounding the many bogs along the edges of the great coniferous forests of this region of Canada.
The female palm warbler lays four to five eggs, but both parents will stay busy collecting insects once the young hatch. On an insect-rich diet, the young birds develop quickly and are able to leave the nest in 12 days. They will remain with their parents as their wings strengthen and they learn to fend for themselves.
While not able to flaunt vibrant plumage like such relatives as the Cape May warbler or the American redstart, the palm warbler is not truly as unattractive as a first glance might suggest. In fact, one subspecies, known as the “yellow palm warbler,” is quite dramatic in appearance with a profusion of yellow feathers accented with a bold russet cap and dramatic rufous striping across the yellow underparts. Even in autumn, the other palm warblers are not devoid of color. Most palm warblers show a splash of bright yellow on the throat and beneath the tail.
In fall migration and during the winter season, palm warblers often inhabit weedy fields, grasping the dried stalks of tall weeds as they forage for berries, seeds and insects and their larvae. Look for the spot of yellow beneath the warbler’s tail, which is constantly bobbed up and down as the bird goes about its routine. The tail-bobbing behavior is a good way to distinguish this warbler from the sparrows of similar size and brown coloration that often share the fields and woodland edges.
The bird walks at Sycamore Shoals State Historic Park will continue each Saturday in October. Participants should meet in the parking lot at the park’s visitors center at 8 a.m. for a 90-minute stroll along the gravel walking trails. The walks are conducted by the Elizabethton Bird Club and are free and open to the public. Bring binoculars to increase viewing enjoyment. Chances are good that palm warblers will be seen on the walk, but with our fine feathered friends, nothing is ever guaranteed.