The Warblers

By Al Lowe
Contributor

We have about 25 species of Warblers here in Northwestern Ontario. While many of these little birds are mainly yellow or green, we so have some which, to say the least, are coloured differently. Here are some:
Black-throated Blue (Dendroica caerulescens).
This one is anything but yellow or green. As its name says, its throat, face and sides below its wings are already black. Wings, tail and top of its head are dark grey-blue. It has a bit of white on the edge of its tail.
The female is altogether different. Top parts are olive green, with a white slash through the eye. Underparts are pale yellow.
No other warbler is even remotely coloured like this male bird. He is indeed unique.
This fellow builds a nest a few feet from the ground in open woodlands. It seems to prefer those areas which were once logged over.
Breeding range is from the Ontario/Manitoba border to Nova Scotia and down into the Eastern United States.
Black-throated Green (Dedroica virens)
Again, as indicated by its name, its throat and breast are dark black. Top of the head and down the back are olive-green, but the sides of its head and its neck are bright yellow. The belly and underside of the tail are white. This one is quite a dandy too!
The female is, as always, duller than the male, although the pattern is similar. She has the yellow cheeks and olive back, but, instead of the black throat, she has some blotchy feathers which tend to run vague stripes on her sides.
This one is found from Alberta east to Labrador, and down into the US (largely in the Appalachian Mountains).
Its nest are in evergreens, at various heights. This is another one which is quite fond of logged areas, especially where there are some mid-sized evergreens.
Take note that there is also a Black-throated Grey Warbler, but he makes his home in British Columbia.
These are a couple of the warblers which are very fond of the Spruce Budworm. At times, the numbers of these little birds rise and fall according to the budworm population. With heavy infestations, they may raise two or even three broods a year.
Take note that the wonderful colours I have noted are those of the male birds in the spring, mainly. This is the breeding plumage. They molt most of their fine feathers in the fall, when they almost all turn dull olive-green or yellowish. So look for them in the spring and early summer, when they are decked out in their bib-and-tuckers.
In an area whose economy is largely driven by the forestry industry, these little birds are our most faithful allies. They eat insects all the time as they live on them. Without these tiny protectors, the forest would simply disappear in a few short years.