A couple days ago we had a special visitor at the feeders. This one had come all the way from the coast of Hudson Bay, or perhaps even further. He was here with a flock of his cousins, who had probably travelled shorter distances than he had, although some of them may have been long-distance voyagers as well. He was a Hoary Redpoll.
Common Redpolls breed throughout the scrubby, stunted forest-tundra of the Hudson Bay Lowlands and surrounding regions. They are found through perhaps the upper quarter of Ontario. Even still, despite their name, they are not an incredibly common bird. The recent Ontario Breeding Bird Atlas indicates that the probability of encountering one in the first 20 hours of fieldwork in the Hudson Bay Lowlands is just 34%. Even less common is the Hoary Redpoll, and the probability of finding one of them is a mere 1%. All of the squares where the species was recorded were right up at the coast. The Ontario birds are the most southerly breeding population of the species in the world; most individuals occur further north than they are found here. To put in context the breeding location of these birds, they are found in the open tundra, placing their nests in willow thickets surrounding ponds, or in the stunted spruces scattered across the small ridges. They line their nests with ptarmigan feathers and Arctic Fox fur. That’s how far north they live.
Like Common Redpolls, Hoarys will migrate southward most winters, but appear in southern Ontario primarily in irruption years. I have seen, and identified, just 5 Hoary Redpolls in the years I’ve been birding. Three of these were in the fall of 2007, when we caught a huuuuge flock of redpolls at the research station, hidden among which were the Hoarys. The other two have been at our feeders this winter. The first one we didn’t get a very good look at, and it didn’t stick around. This is the first and only adult male that I’ve had good looks at.
You can tell it’s an adult male by the rose wash to its breast. Females will show no colour to the breast, though they’ll look nearly the same otherwise. Young males may be intermediate.
Part of the problem with identifying Hoarys is that they can look so similar to the Commons they hang out with. There are a few key identification features, the easiest of which to spot is probably the pure white undertail coverts. Look at the way the Hoary’s butt glows in the first photo. Of course, just like any good identification rule, it has its conditions. In this case, only the adult males have pure white undertail coverts. The females may show a streak or two, and young birds show more streaking than adults. However, all age/sex classes show proportionally less than the same age/sex class of Common Redpoll. Okay, so that doesn’t really help when you’ve got a young female Hoary beside an adult female Common (the males, of course, would have rose breasts). But hey – the young female Commons and adult male Hoarys should be no problem!
The photo above, of course, is a Common. Age/sex class undetermined.
Another fairly easy to spot characteristic is the head shape. Hoarys look like they have little heads for the size of their bodies. They’re not as deep, I guess, from bill to nape as a Common is, relative to the body. It gives them a pin-headed appearance. Added to this is their small, stubby bill, compared to that of a Common. At some angles these two features aren’t as apparent. A full profile shot with the bird looking downwards really emphasizes the shape, however.
Here’s another shot of the heads, Common on the left, Hoary on the right. The name Hoary, of course, comes from the pale colouration of their plumage compared to Commons. The word Hoary, interestingly, means “gray or white with, or as if with, age.” There are a few species named Hoary – the redpoll, of course, but also Hoary Marmot and Hoary Bat. Their fur is all white-tipped with a grizzled appearance. I suppose “Hoary Marmot” sounds better than “Grizzled Marmot”, although there’s the Grizzly Bear – same origin. Grizzly Marmot?
One last thing you could look at is the bird’s rump, although this can sometimes be hard to spot if the bird has its wings closed. However, if you can get a peek at it, it follows the same general pattern of plumage as the undertail coverts: Commons are streaky, while Hoarys are white. You can just get a hint of the Hoary’s rump in the photo on the right.
Here’re two males, the Hoary and a Common, side-by-side on the feeder. You get a sense of the lightness of the Hoary compared to the Common. You can also notice the difference in the streaks on the sides. In younger birds, this can often be useful in picking a Hoary out of a flock. Hoarys generally have thinner, more distinct streaks, while those of Commons are broader and diffuse.
These last two photos, above and below, are of young female Hoary and Common Redpolls, side-by-side. These were the birds we caught in 2007. Having them up close, in the hand, was a huge advantage, but you can see the field marks you’d be looking for even if they were out sitting on a perch somewhere. I’ve been periodically checking out the birds at our feeders, looking for a possible female Hoary that had snuck in with the Commons, but hadn’t spotted one. Then this male showed up, which made the ID so much easier.
(My spellcheck is telling me that “snuck” isn’t a valid word. What?)
There is some debate as to whether these two are, in fact, different species, or simply subspecies. Visually, even though it’s subtle, they do appear to be different species, but molecular studies suggest there’s not enough evidence for that. In Europe the Hoary is known as the Arctic Redpoll, and it’s the North American subspecies of Hoary that gets the name Hoary applied to it.
I was pleased to see this rare visitor at our feeders. Now we just need to attract some grosbeaks!