Foam Lake Birding No. 46

No. 46
In the week following my last article, Tree Swallows, Gold Finches, White Throated Sparrows, Clay-coloured Sparrows and Harris’s Sparrows have finally arrived. In checking our past records, we found that most of these birds come here about the last week of April and not the second week of May as has happened this year. Oh well, better late than never.
There is one more transient bird that I want to cover this spring – the Swainson’s Thrush. I feel that it is a good bird to feature, as it comes to our yard every spring without exception, and probably will in yours. Birders can be quite sure that they will be rewarded by the presence of a Swainson’s Thrush in their yards.
In older bird books, the Swainson’s Thrush is called the Olive Backed Thrush, but a few decades, ago ornithologists renamed it after British naturalist William Swainson. Swainson was a self taught amateur biologist from Liverpool who traveled extensively around the world in the early 1800s studying all forms of living things. Being a gifted artist, he added many sketches, drawings and paintings to his many written works. To honour him and his work, ornithologists named three birds after him: the Swainson’s Hawk (common around here), the Swainson’s Warbler (rare in Canada) and the Swainson’s Thrush. The birds were not named after him in one fell swoop, as it were. Audubon named the warbler; Bonaparte (an early nineteenth century ornithologist and not the emperor of France) named the hawk; present day ornithologists renamed the thrush. (Both, Audubon and Bonaparte, have birds named after them.)
The Swainson’s Thrush is closely related to the very familiar Robin. In fact, it has the same profile and behavior patterns as a Robin. Like a Robin, it spends a lot of time in gardens and lawns looking for worms. A freshly tilled garden is especially attractive to them (and to Robins). Perhaps the worms are brought to the top?
A general description for purposes of identification is to look for a very large “sparrow” that behaves like a Robin. Some even describe it as a little brown Robin. A sure way to tell a thrush from a sparrow is to watch its movements when it is feeding on the ground. A sparrow hops as it darts from place to place; a thrush runs. In size, the Swainson’s Thrush is about halfway between a sparrow and Robin. The top of the head, back of the neck, wings and tail are a medium brown in colour; the back is olive brown; the breast and belly are whitish with the upper breast having a buff tinge to it. The upper breast is, also, covered with spotted streaks running more or less vertically. The buff colouring extends to the bird’s cheeks and thin eye rings. However, to see these buff features one almost needs binoculars. Its song has been described as a series of flute-like whistles. To me, it sounds vaguely like a Robin singing very softly and far away in a deep forest.
The only common birds that it can be confused with are the various sparrows, but look for the distinctions described above. However, it does have two close cousins, the Grey Cheeked and Hermit Thrushes, which are very similar to it in all respects. The key distinction is that neither one has any buff colour on it – especially the eye ring. Only the Swainson’s Thrush has a buff eye ring. In other words, a little brown thrush without a buff eye ring is either the Grey Cheeked or Hermit Thrush. If one of the “other” ones has a rusty brown tail that is very noticeable in flight, it is a Hermit Thrush. All three are considered excellent songsters; all three sing with flute-like whistles. The Hermit Thrush’s song is considered the most beautiful of the bunch.
There is one other thrush that is a close relative to the Swainson’s Thrush – the Veery. In our area it is a summer resident and not a transient. Because it needs larger stands of mature trees, it is very seldom seen in town. Of all of the little brown thrushes, the Veery, has very little or no striping on its breast, thus making it very easy to identify. I plan to do a piece on this bird in the future.
Even though the last three are uncommon in town, they do occur. A keen eye might notice, and then identify, some of these species. There is nothing more satisfying to a birder than identifying an uncommon or rare species.