"Lawrence's" Warbler in the Wildflower Meadow
A rare and somewhat cooperative "Lawrence's" Warbler has been hanging around the Wildflower Meadow since last Friday or Saturday. I have photographed it over several days but it wasn't until this morning that I got a couple of nice shots.This bird is a hybrid of the Golden-winged and Blue-winged Warbler. According to the Cornell Web site:
Where their ranges overlap, you may find a "Brewster's Warbler" or the lesser-known "Lawrence's Warbler," which are hybrids resulting from a pairing between Golden- and Blue-winged warblers. A great deal of variation exists in these hybrids reflecting the interactions between dominant and recessive genes. The white underparts of a golden-winged and the reduced facial pattern or black eye-line of a blue-winged are dominant traits, whereas the yellow underparts of the golden-winged and the broad facial pattern showing black ear and throat
patches are recessive traits. "Brewster's Warblers" exhibit the dominant traits, and "Lawrence's Warblers" exhibit the recessive traits. Just as people with the recessive trait of red hair are relatively uncommon, the comparative rarity of the "Lawrence's Warbler" is the result of a naturally rare combination of recessive genes. See Peterson's Field Guide to Warblers by Dunn and Garrett for more details.
These genes interact in ways we don't yet fully understand. During GOWAP's Spring 2000 field season, participants spotted several birds with unusual plumage near Upstate New York's Cayuga Lake basin. One had the overall appearance of a Blue-winged Warbler but with a ragged black throat-patch. A similar bird had its otherwise yellow throat covered with large black spots. These rare plumage types do not fit any field guide descriptions. John Confer, associate professor of biology at Ithaca College, says these plumage types suggest there may be more than two pairs of genes involved in determining plumage variations between Blue-winged and Golden-winged warblers. Studying these unusual hybrids may help us understand the genetic basis of the hybridization between these two species. And because these birds sing hybrid songs, we may be able to explore the role of heredity in the birds' song formation.
