Which Neotropical migrant is the first to return to the US each spring?
When most of us think of “neotrops,” colorful images of warblers and tanagers spring to mind. In fact, though, a number of non-passerines also breed in North America and “winter” south of the Tropic of Cancer.
One of those non-passerines, Baird’s Sandpiper, is among the earliest of northbound migrants, reaching the central Great Plains by early March.
Baird's Sandpiper--here a southbound bird in July--moves north from its tropical wintering grounds in early spring. Photo: Rick Wright
With thanks to Ted Floyd.
I’d say that Baird’s Sandpiper is beat out by two months by Purple Martin (Progne subis), a bird that is only known to winter in Amazonia and areas of similar latitude. The first Purple Martins, primarily males, return to the immediate Gulf Coast of the United States by the second week of January, with females usually present by the end of the month. There is an interesting step in dates of returns, however, as the bulk of the population waits until at least March before invading farther inland!
Dan’s quite right, and I was thinking sloppily when I dismissed Purple Martin, a species that is indeed present in the US significantly earlier than Baird’s Sandpiper.
As Dan notes, the martins seem to hang around at the coast for some considerable time before pushing north, such that Baird’s Sandpiper–the swallows’ headstart notwithstanding–actually arrives a month or more earlier than they do in the interior.
rick
How should I understand “neotropical migrant”? If wintering south of the Tropic of Cancer is the only qualification, the migratory subspecies of Allen’s Hummingbird would seem to be a contender, as well, arriving on its breeding grounds here in the Bay Area by late January. But maybe central Mexico doesn’t measure up to our usual notion of the Neotropics!
A good question, that one! Have a look here: http://elibrary.unm.edu/sora/Auk/v112n02/p0521-p0523.pdf
Hayes suggests that we call these birds “nearctic migrants,” reserving the more common term “neotropical migrant” for South American species that move north in the non-breeding season (“austral migrants”).