By Bryan Stevens
This fall has been a good time to see warblers. Some of the more common ones I have noticed in the yard so far have included American redstart, chestnut-sided warbler and black-throated green warbler. Of course, these two species nest in the region during the summer.
One of fall’s first true migrants showed up on Sept. 17 when a rambunctious Tennessee warbler made its debut by chasing a male Northern cardinal from the blue spruce near the creek.
The pioneering American ornithologist Alexander Wilson gave the Tennessee warbler its name, which, unfortunately, is not an accurate moniker.
Here’s some trivia for you should you ever find yourself competing on the game show “Jeopardy” and the category is “Warblers.” Four of our warblers — Kentucky Warbler, Louisiana waterthrush, Connecticut warbler and Tennessee warbler — bear common names that honor states. The Kentucky warbler and Tennessee warbler are named for the states where they were first found and described by Wilson in 1811. Neither the Tennessee warbler or Kentucky warbler are particularly affiliated with the states for which they were named. In fact, the Tennessee warbler passes through the Volunteer State only for a few weeks each year during spring and fall migration. Its closest breeding range is in the boreal forests of Michigan, and these warblers spend the winter in Mexico or farther south. Wilson got lucky and found his Tennessee warbler along the Cumberland River during migration.
Don’t blame Wilson too harshly for the mistake. Even after he “discovered” the first Tennessee warblers back in 1811, it would be almost another century before scientists finally located the bird’s nesting grounds in Canada in 1901. The remote and inaccessible nature of the region helped prolong this mystery about the Tennessee warbler’s life cycle.
In almost 25 years of birding, I’ve never seen a Tennessee warbler during spring migration. I see many of these birds every autumn as they stage their fall migration through the Volunteer State to reach destinations farther south. The appearance of the Tennessee warbler varies greatly depending on the season. In autumn, most Tennessee warblers are greenish-yellow birds with whitish-gray underparts. In the spring, the basic green and white pattern remains evident, but both males and females sport a gray head and a black line that runs through the eye and along the side of the bird’s face. The plumage — at least in illustrations and photographs — is shown as more crisp and distinct with spring birds.
Some experts have floated the opinion that the Tennessee warbler should be named “coffee warbler,” since wintering individuals are attracted to coffee plantations in Central America. According to the website, “Birds of North America,” recent studies demonstrate the importance of shade coffee plantations for Tennessee warblers during their time spent outside North America every winter. Other warblers, such as the black-throated blue warbler, are also closely associated with coffee plantations during the wintering season.
Some years find Tennessee warblers in great abundance, probably thanks to a feast of caterpillars infesting the spruce trees in the boreal forests where these warblers nest during the summer months. In years of famine when the caterpillars are less rampant in the forests the Tennessee warbler calls home, the birds raise fewer young, and the population grows less dramatically.
The Tennessee warbler is not strictly an eater of caterpillars and insects. This warbler has a bit of a sweet tooth — or should that be sweet beak? They visit flowers to partake of nectar; however, the Tennessee warbler is not a good example of an avian pollinator.
Tennessee warblers cheat by poking holes in the flower with their bills to steal the nectar without having to let the flower’s pollen accumulate on their bills and heads. The Tennessee warbler will also come to sugar water feeders put out on their wintering grounds to attract hummingbirds. The Tennessee warbler also supplements its diet with fruit and berries.
Here’s something that might also come in handy in a test of your knowledge of trivia some day: Not only is the Tennessee warbler named for the state, but the capital city of Nashville also has its name linked another member — the Nashville warbler — of the warbler clan. Once again, Wilson provided a rather inaccurate name, as the bird in question is only a visitor to Nashville during a limited window of time each year.
While the briefly visiting Tennessee Warbler already pays tribute to our state with its common name, the Northern mockingbird was selected in 1933 as the official bird for Tennessee. This relative of the brown thrasher and gray catbird also serves as the state bird for Arkansas, Florida, Mississippi and Texas.
At my home, Northern mockingbirds are usually evident only during the winter months. I haven’t seen one at home so far this year. Gray catbirds were scarce this summer, but a pair of brown thrashers provided much entertainment as they raised young in my yard and gardens.
For now, I think Tennesseans will probably stick with the mockingbird, rather than the Tennessee warbler, when it comes to offering one of our feathered friends the accolade of official state bird. That’s not to say we can’t enjoy observations of this warbler during its brief forays through the state. Don’t wait too long, though. The window of opportunity usually closes by mid-October.
I will be conducting morning bird walks at Sycamore Shoals State Historic Park in Elizabethton every Saturday in October. Walks begin at 8 a.m. from the parking lot at the park’s visitors center. The walks are free and open to the public.
Bring a pair of binoculars to increase viewing enjoyment as participants scan for warblers and other migrants visiting the park. Email me at firstname.lastname@example.org for more information.