BAY-BREASTED WARBLER(Setophaga castanea) – (See images below)
DESCRIPTION: The Bay-breasted Warbler breeding male has a black face and chestnut or bay-colored head and breast. This color extends down the sides of the breast as well. It has two white bars on the grey wings. There’s a creamy patch on each side of the neck. Under parts are creamy. Bill and legs are black. Females have some chestnut-bay color on their sides. The face is grey and the back grey-olive green, and they have two white bars on their grey wings. The bill and legs in the female are grey. The birds is around 13 cm (5 inches) long.
NAME: The English name ‘Warbler’ means ‘to sing with trills and quavers’.  The genus Latin name ‘Setophaga’ means ‘to eat moths’, in reference to the bird’s diet. The Latin species name ‘castanea’ refers to the chestnut color of the plumage.
HABITAT: Mainly coniferous forests.
DIET: The Bay-breasted warbler feeds on insects and spiders in the summer, and fruit in the winter.
NESTING: The nest is built on a conifer branch in a well concealed location. About five or six white eggs are laid, incubated by
DISTRIBUTION: Breeding range encompasses the Canadian boreal forest except the Rockies, especially spruce and fir. During migration it is found in the eastern half of the USA and around the Gulf of Mexico. The wintering grounds cover part of southern Central America and the northern tip of South America.
ON PEI: The bay-breasted warbler breeds on Prince Edward Island,  and is fairly common on the island in the spring and summer.
CONSERVATION: Although the Bay-breasted warbler is not on any list of threatened species at the present time, its numbers have declined sharply over the last few decades – by some 70%. This number also fluctuates in relation to spruce budworm infestations, as that pest is part of the bird’s diet. This negative trend in the population appears to be related to spruce budworm spraying and lost of wintering habitat.
NOTES: The bay-breasted warbler is hard to localize and identify because it has the habit of perching in the thick of conifers.
There are known hybrids between the bay-breasted warbler and the Blackpoll Warbler, a closely related species. It can also hybridize with other warbler species such as the Yellow-rumped Warbler and the Blackburnian Warbler.
SIMILAR SPECIES: Chestnut-sided Warbler, Blackpoll Warbler, Cape May Warbler
REFERENCES: (Maritimes Breeding Bird Atlas)
American Bird Conservancy (Bay-breasted Warbler) (Missouri Department of Conservation)

Bay-breasted warbler, breeding male - Rondeau Provincial Park, Ontario - photo by Mdf
Bay-breasted warbler, breeding male – Rondeau Provincial Park, Ontario – photo by Mdf
Bay-breasted warbler, female - photo by Dan Pancamo
Bay-breasted warbler, female – photo by Dan Pancamo