The first indication that the yellow warblers (Setophaga petechia) have returned is the lilting song of the males in our hybrid poplars. Take a careful look and sure enough, these tiny birds are flitting about high in the treetops.
Yellow warblers are long distance migrants that spend the winter in the mangrove forests of Central and South America and the breeding season in central and northern North America, going as far north as the Arctic tundra. It always amazes me that these small avians can make that long journey twice each year.
Although there are about fifty warbler species that breed in North America (most are in the East) the yellow warbler is easy to identify. The male is a brilliant yellow with chestnut streaking on the breast during the spring. Females and eclipse (non-breeding) males are duller without the streaking, but still entirely yellow. These warblers have no head markings, the black eye is prominent and the bill is black.
In constant motion, yellow warblers hop about from branch to branch in search of the midges, leafhoppers, caterpillars and other insects that they pick from the foliage. They also hover briefly as they search for food. Since they never seem to stop moving and are high in the trees, yellow warblers are frustrating to photograph.
Yellow warblers can be found nesting in shrubby thickets and woods, especially near water. Since there is no water on our property (Lookout CA) we only have them nearby in the early spring when our poplars are covered with catkins. Pairs are monogamous and remain together over several breeding seasons. When cowbirds, notorious parasitizers of other species’ nests, lay their eggs in a yellow warbler nest, the warbler will abandon both its eggs and the cowbird eggs and build a second nest on top of the original nest.
Dendroica petechia is another scientific name for the yellow warbler.