Chestnut-sided Warbler, Setophaga pensylvanica


Chestnut-sided Warbler
Above, a singing male in breeding plumage; below, a month later in the year in the same place, Deer Isle, Maine, a male molted to non-breeding plumage.


Chestnut-sided Warbler

Chestnut-sided Warbler
The more extensive black mask and chestnut stripes distinguish the breeding-plumage male, above, from the female, below. The female is gathering nesting material in July, presumably for purposes of repair.


Chestnut-sided Warbler


Chesnut-sided Warbler