On Thursday, I was walking the dog near Sutton Mills and heard a loud, rich two-part song sounding repeatedly from 20 or 30 feet up in some hemlocks. Initially illusive, the bird moved to a red maple in the process of both flowering and leafing out, where I got a reasonably good look at it. The dog was being surprisingly good, only tugging a little on the leash looped around my wrist and jiggling the binoculars a bit. But I saw a greenish back, bright yellow chest and sides, grayish head and some white around the eye. The song consisted of repeated two-note phrases at roughly the same pitch, followed by a trill. I didn’t recognize it, but thought the singer might be a mourning warbler, a bird I have never seen.
At home, I sat down at my computer to bring up www.allaboutbirds.org, which provides access to recordings at the Cornell Laboratory of Ornithology.
It was not a mourning warbler; that bird’s song is a repeated two-note phrase with no terminal trill. Furthermore, the mourning has no white around the eye.
The Connecticut warbler, while otherwise resembling the mourning, does have a white eye ring. But its song is entirely different from what I heard.
This left the Nashville warbler, also green-backed with yellow below, gray around the head and a white eye ring. While the gray extends in a bib across the throat of the Connecticut and the mourning, the Nashville’s throat is bright yellow. My bird was back-lit and I did not get a good look at the throat, but when I heard the recorded song it was a perfect match. I had found a male Nashville warbler singing solidly in the middle of its breeding range in habitat it is supposed to like: mixed forest with shrubby undergrowth.
The Nashville warbler is seldom seen in its eponymous Tennessee city. Early republican ornithologist Alexander Wilson shot the type specimen near Nashville in 1811, but that unfortunate bird was migrating. This species breeds in the northeastern U.S. and in Canada, with a disjunct population in the northwestern U.S. and the Sierra Nevada.
The Connecticut warbler is even more poorly named. Its breeding range is in the southern taiga of central Canada, and even during migration it rarely ventures as far east as Connecticut. As luck would have it though, Alexander Wilson once again shot a migrating bird and gave it an unsuitable handle. So, eye ring or no, it would be unlikely for me to see one of these in central New Hampshire, even during migration.
Several other warblers have been given geographically or biogeographically misleading names. The Cape May warbler is a very uncommon migrant at the famous southern New Jersey peninsula. By this time you will not be surprised to learn that Alexander Wilson enters the picture again. In 1809, he was given a male specimen collected by George Ord at Cape May. The Cape May warbler was not seen again at its type locality for a century.
According to my 1917 “Birds of America,” the migrating Cape Mays became more common in the Eastern Flyway in the early 20th century. Although its breeding range stretches across the entire Canadian taiga (in New Hampshire it breeds only north of the White Mountains) and winters throughout the Caribbean, the bulk of migrants formerly went through the Central Flyway.
The Tennessee warbler has a breeding range similar to that of the Cape May. In other words, most of them are Canadian, although it does nest in New Hampshire as far south as Merrimack County. Once again, however, a migrating bird gave the species its common name, although this time Mr. Wilson seems not to have been involved.
There are some biogeographical misnomers too.
The prairie warbler is not particularly common on grasslands. It actually prefers a habitat of shrubs and early successional second-growth forests. It is a southern bird; southeastern New Hampshire marks the northeastern edge of its breeding range.
The palm warbler spends its winters among the palmettos of the southeastern states, but nests in the coniferous forests of Canada. Likewise the magnolia warbler will only encounter said tree during its migration to its wintering grounds in the Caribbean. It nests alongside the palm warbler amid the spruces and firs.
To make matters more confusing, some geographical warbler names are more or less accurate.
The Louisiana waterthrush does breed in that state, but it also breeds in this one and every state in between.
The Kentucky warbler does nest in the Bluegrass State and, in fact, it is essentially the center of its breeding range.
And yes, the Canada warbler does breed in Canada, but also in the Appalachians as far south as North Carolina.
This confusion associated with common or vernacular names is one reason there are scientific names with a binomial nomenclature. Unfortunately, that too can be a mess. Good old Alexander Wilson initially called the Nashville warbler “Sylvia ruficapilla,” assuming the New World warblers were related to the Old World warblers (which actually warble).
In 1827, William Swainson, an English naturalist (who has a warbler and a hawk named after him), created the genus Vermivora, and moved the Nashville into it. But in the early 21st century, Vermivora was broken up, and the Nashville was briefly placed in the genus Oreothlypis. In 2008, Dutch ornithologist George Sangster created a new genus,, with the Tennessee warbler as the type species, and the Nashville became Leiothlypis ruficapilla.
However you classify it, the bird is beautiful and has a pretty song.
Bill Chaisson, who has been a birdwatcher since age 11, is a former editor of the Eagle Times. He now works for the Town of Wilmot and lives in Sutton.