Friday, September 21, 2018
New Bird Sighting on the Tuolumne Parkway Trail: Nashville Warbler
The warbler clan shows the effect of isolation on the evolution of these birds. The western population of the Nashville Warbler is a brighter yellow than those found in the eastern United States, and it was once considered a separate species called the Calaveras Warbler, a name I find much more interesting. We can still call it by that name, since it is officially a subspecies called Oreothlypis ruficapilla ridgwayi.
Oh, and by the way, the bird has little to do with Nashville. It breeds in Canada and the Pacific Northwest and migrates in winter to the tropics. The ones seen in Nashville that gave the species its name were simply migrants passing through.