The Yellow-Rumped Warbler

Thu, 02/18/2021 - 6:45pm

The following was submitted to The Block Island Times by the Block Island Conservancy:

The yellow-rumped, or Myrtle, warbler is a migratory and wintertime songbird on Block Island. It is the only warbler that regularly spends its winter on Block Island, due to the fact that it is one of the few birds that can eat and digest bayberry, a waxy seedy fruit that is commonly found all season long on the island.

Yellow-rumped warblers are fairly large warblers with yellow patches on their flanks and, of course, on their rump. The patch of yellow just above their tail feathers is most noticeable when the bird is perched. They have a long, slender tail with white patches on the outer feathers. Breeding males have a slate-gray back and a black facemask that offsets a white throat, while females, immature, and non-breeding males are duller and more brown in the head and back.

In addition to eating bayberry while spending the winter on Block Island, yellow-rumped warblers will also feed on juniper berries, poison ivy berries, and seeds from beach grasses and goldenrod.

After spending the winter on Block Island, yellow-rumped warblers move north to spend their breeding season in primarily coniferous forests. While in these forests, yellow-rumped warblers hunt for insects by clinging to trees and searching for spiders, caterpillars and other larvae, and notably, the spruce budworm, which is a serious pest. They will also sit on the ends of tree branches and sally out, like flycatchers do, to catch insects on the wing.

The best places to see yellow-rumped warblers right now on Block Island are in shrubby areas that contain bayberry, such as at Clay Head. Keep an eye out for the bright yellow rump patch and a flash of white in the tail!