Yellow Warbler —Ross Feldner The Yellow Warbler is the champion of yellow among warblers as well as being the most widespread American wood-warbler, nesting from Alaska to northern South America. Birders usually first seek these difficult to spot warblers with their ears, listening for their distinct song, and then searching with binoculars. The Yellow Warbler diet consists mainly of insects and spiders which they hunt from branches and shrubs grabbing them in mid-air providing great pest control. A study in Costa Rica, where they winter, showed that the Yellow Warbler reduced the population of coffee berry borer beetles by 50%! Brown-headed Cowbirds often lay their eggs in the nests of Yellow Warblers, but Yellow Warblers have developed an adaptive response to this parasitism: When it detects a cowbird egg it its nest, it either abandons the nest (including its own possibly doomed eggs), or it builds another nest on top of it, effectively stopping the incubation of the cowbird egg. Yellow Warblers, like many birds in America, are threatened by habitat loss, mostly destruction of riparian habitats, and the overuse of pesticides. | |
