It is the time of year again when we see warblers wending their way south for warmer climes. No COVID restrictions for these international travellers. Lucky birds.
Warblers are small, active insect eaters with short, pointed bills. We see them in the woods that edge our cottage, our cottage road, and the marshes that border White Lake. Some species of warbler are quite colourful but many come in various shades of brown, beige, olive, and yellow posing a great challenge for us to spot, then later to identify the species in the photographs taken by our intrepid photographer. Some sexual dimorphism exists, but we are often confounded by the variations, especially between spring and fall, juvenile and adult. Spring males in their brighter, breeding colours are less difficult to identify but the autumn … oh how the muted autumn colours baffle us. Sometimes we despair.
All of our warblers are small birds, most less than 10 centimeters in length. Many have weak songs, but a few have loud voices. They nest in dense bushes, thickets and deciduous trees, depending on the species.
One of our warblers … the pine warbler … prefers nesting well up in tall conifers. It is a good example of a species we find difficult to identify. The experts describe the pine warbler as having olive-green upperparts and yellow below which, to our old eyes, sometimes varies through drab shades of grey and beige. This is especially true for first year fall individuals. Its name is derived from its preference for pines. In addition to insects, the pine warbler eats spiders, pine seeds, and berries. It joins resident warblers in the United States south east for winter where the pine warbler sometimes forms aggregates of up to 150. We would love to see that … a cone of pine warblers.
One would think, given the photographs used by various birding experts, the yellow-rumped warbler would be fairly easy to identify. Sometimes it is, but as often as not, especially in the fall, it seems to be just another cute, little brown bird. Only if we are patient and lucky do we see its yellow sides and/or yellow rump-patch above the tail feathers which enables us to make an identification. The yellow-rumped warbler spends the winter through much of the middle and south eastern United States.
One of our favourite warblers is the common yellowthroat. The male is easily distinguished by its distinctive black mask. The female, on the other hand, with its yellow, buffy, brown colouring stretches our skills to the point of snapping. This pretty female common yellowthroat contrasts with the one we showed to you in last month’s article, showing just how pale the female yellowthroat warbler can be. The common yellowthroat winters in the southern United States and as far south as Mexico and Central America.
A rare warbler for us to see at White Lake, the black-throated green warbler has an olive head and back with yellow cheeks and around its eyes. In the fall its black throat becomes mottled with white. The black-throated green warbler is easier to identify than the little brownish species … too bad we do not see it more often. They winter in Central America and the Caribbean where we would like to winter too.
Another of our favourite warblers, which may be the easiest to spy, is the black-and-white warbler. The male’s black and white striped head and body stand out in our cottage bushes. Similar to the black-throated green warbler, the black-and-white warbler’s black throat speckles with white in the fall. In behaviour, this warbler resembles more closely the brown creeper, as it hops along tree trunks and branches close to the ground. It builds its nest in small depressions in the forest floor. The black and white warbler also winters in the tropics.
Chris Early’s advice to beginners is to learn to identify the warblers in the spring when they sport their brighter, more distinctive breeding colours. With time this knowledge will develop one’s ability to recognize their shapes and behaviours in the fall. All we can say to that is … we’re trying, Chris. We enjoy trying. We hope you do too.
Our research for this article included Jeffrey Dom’s Field Guide to Ontario Birds; Chris Early’s Warblers of the Great Lakes Region and Eastern North America; and, David Sibley’s Field Guide to Birds of Eastern North America. We checked the migration habits of these warblers at allaboutbirds.org.