Fowl-weather restaurant

Hairy Woodpecker

I wouldn’t say that there had necessarily been a lull at the feeders, per se, during the warmer temperatures, but certainly activity was a bit decreased for those few days as birds found it easier to find their own food out in the woods. With the return of the snow yesterday, the feeders were back to normal, bustling with birds looking for easy food. Most of the birds blend in with one another, with no one individual really standing out. The species that we don’t get very many of, however, like the nuthatches, are more likely the same individual visiting frequently (in the case of the Red-breasted Nuthatches, we’re pretty sure there’s only two, and one has the black crown of the male, while the other is a female sporting her grayish crown, which makes it easy to tell them apart).

There are a couple of individuals that we banded a little earlier in the winter and who are continuing to come round to the feeders. One of them is this male Hairy Woodpecker. I haven’t noticed the banded female recently, but this male is a regular. Here he is proudly displaying his jewelry while he checks out the activity at the nyger feeders (he eventually left without trying the seed).

Feisty siskin

Another is this banded siskin, the only banded siskin that I’ve noticed still hanging around (though Dan indicated he thought there might be two). The others have most likely headed north already, given their fat levels when we caught them. Even the couple of banded redpolls I’d observed for the first little while after they were captured have now disappeared, leaving just this lonely individual still hanging out at the feeders. It can’t be that s/he’s having trouble finding enough food to put on the fat, because s/he dominates the feeders. Just as feisty as always, she (or he) reaches up to take a nip at an offending redpoll.

Redpoll party

It’s been hanging-room-only at the feeders the last couple days, as the snow arrived and birds started scrambling for food. They’ve been plowing through the seed, easily going through half a tube’s worth over the course of a frenzied day. I wonder just how much food each bird actually ingests during all this squabbling. Obviously some will get more than others, but it seems like half their time is spent shooing others away, rather than just sitting and eating.

Redpoll group

When not at the feeder, those birds that turn their beaks up at foraging on the ground will wait their turns on the surrounding branches. There’s easily just as many, or more, birds lined up along the twigs as there are on the feeder itself. I love the collection of little red caps and yellow beaks against the browns and grays of the winter landscape.

Keeping an eye out

At one point something went overhead and all the birds at the feeder went stock-still, except for their heads which they rotated sideways to point an eye up at the sky. I’m not sure what it was they spotted – it could have been a hawk, after all we had that Sharpie around a little while ago. It could have been a raven soaring over, looking hawk-like in profile as it cruised overhead; certainly we’ve had plenty of those about during the winter. Possibly a Red-tailed Hawk, moving low overhead. I’ve seen one or two around over the course of the winter, though it would be unlikely they’d come down to the feeders. If we were closer to a flight path I might suggest it could even have been an airplane, but we hardly ever see them through here, and when we do it’s pretty easy to hear the engines as they pass by.

Hoary Redpoll

Our male Hoary that we spotted earlier in the winter has apparently hung about, and was active at the feeders the last couple of days. Either that, or it’s a different individual. Either way, he was a nice addition to the feeder crowd. He stood out from the rest, even though he didn’t look quite as pale as the one from earlier. Redpolls only have a single moult to replace their feathers, in the fall, rather than the two that most songbirds have. They acheive their breeding plumage through the gradual wearing-off of the pale feather tips over the course of the winter, exposing the rosy underneath. This process would also expose the brown on his back, probably an advantage during the breeding season when white isn’t as common a colour in the landscape, and would result in him looking paler earlier in the winter than now.

Hoary Redpoll

His pure-white undertail coverts and thin, sparse flank streaking were give-aways, as was the stubby bill when he turned his head. The other thing that jumped out about this individual was his gorgeous rosy breast on a fluffy white background. When he perched on the branches away from the feeder, it was easy to spot him, he had considerably more pink to his chest than the Commons did.

There are two subspecies of Hoary Redpoll. The one that most people probably think of, the stereotyped pale Hoary, is C.h. hornemanni, which has very reduced pink to the breast. It breeds in the Northwest Territories and winters from Michigan to Maryland. The other subspecies, C.h. exilipes, is a little more common, breding from Alaska to Labrador, and wintering right across the continent from Oregon to Maryland.

This latter subspecies isn’t as pale as the first, and, according to the “bander’s bible” which gives the moult details for every age and sex of every species, in the adult male exilipes “the pink of the underparts [is] deep, usually covering most of the breast.” Interestingly, that contradicts his statement later on in the species account where he says the “breast and rump with a light to moderate pink wash”. I just read this latter statement at first and was thoroughly confused about what appeared to be a heavily-marked Hoary, until I read the subspecies description.

This may be my last redpoll post; they’ll be departing soon, headed back to the shrubby tundra lowlands across northern Canada. We can probably expect to enjoy another couple of weeks of them gobbling nyger seed before they’re gone – at least till next winter.

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Feeder bullies

Pine Siskin

You may think by the title of this post that I’m talking about Blue Jays, or perhaps squirrels, but that’s obviously not the subject of the photo above. No, the title refers to a couple of visitors we had to our feeders yesterday, a species we hadn’t seen around our house since the fall, and even then the ones we saw weren’t stopping to hang around. There were just two of them at the nyger feeders, chowing down with a large flock of American Goldfinches. Can you pick her out in the photo above?

Pine Siskin

Here’s a better look at the culprit, a little brown streaky bird that comfortably falls into the “little brown job” category. Pine Siskins are a type of finch that breeds in coniferous forests through most of Ontario, but more abundantly in the north (reflecting the relative abundance of their preferred habitat). They feed on the seeds of conifers, particularly White Spruce, White Cedar and Eastern Hemlock, and in years where these species produce low crops in the north the birds will irrupt south where they are frequently seen at feeders. They’ll often hang out at the nyger feeders with goldfinches, House and Purple finches, and redpolls, although depending on the number of perches you have in your feeder assortment usually the flocks don’t intermingle too much.

Pine Siskin

Superficially the siskins may resemble females of the different Finch species (that is, House, Purple and Cassin’s), but the siskins are noticably smaller than the other species, slimmer, and with needle-sharp bills compared to the thick, bulky finches’ bills. They usually show some sort of wingbar, and, most tellingly, they all sport yellow in the wings, although it can be fairly reduced in females (such as this one). You can just see the yellow edging to the wing feathers in this photo. If you’re outside listening to a flock, their basic chittering sounds like a standard finchy noise, but is periodically punctuated by a characteristic, long, buzzy, rising “Zreeeeee!”

Pine Siskin CBC graph

Population levels are hard to monitor because of the tendency of individuals to wander in response to variable food availability – one year the big crops will be over here, the next they’ll be in this other spot, and so counts at any given spot will fluctuate greatly. This is true of both winter and summer populations, since there’s no point in raising a brood in an area where there’s no food. Pooling Christmas Bird Count results from Canada and the US since 1950 show no real long-term trend in populations. However, they do show huge variation in abundance from one year to the next, almost biennially. It’s an interesting graph; you can dial up more CBC results here.

Pine Siskin

Siskins don’t share the feeders well. This scene may look relatively peaceful, but it was one of just a handful of photos I got that looked like that. Most photos showed variations on this theme:

Pine Siskin

The siskins would throw out their wings and extend their heads to snap at the neighbouring goldfinches. Goldfinches squabble among themselves a fair bit, but usually aren’t all that forceful about it. They’ll stand up to each other, snap back and forth, before one finally gives in. They all respected the siskins, however.

Pine Siskin

Okay, okay! Don’t hurt me! The seed’s all yours!

Often departing rapidly. Check out the yellow in the wings.

Pine Siskin

Hey, shove over, punk! You’re in my personal space!

Pine Siskin

Your mama had chicken legs!

Pine Siskin

Finally. Room to eat in peace.

Winter bird irruptions

Common Redpoll

I have more to add to the winter colours theme of the last couple of posts, but feel like a change of pace today. I haven’t done any posts yet about birds, which is a little surprising given that birds are really my primary interest in nature (first birds, everything else second). So here’s a post on birds.

This winter, southern Ontario, and indeed most of northeastern North America, is enjoying a phenomenon called “irruption”. An irruption is similar to migration in birds, but takes place irregularly, usually every two to four years (depending on the species), rather than every year. Most irruptions are the result of food shortages in the areas where the birds usually spend their winters. Because the birds can’t find sufficient food there, they start to move south in large numbers. In many of these species, small numbers may be seen every winter, but an irruption is marked by a great abundance of the species south of its usual range. This winter seed crops, especially of deciduous trees, did very poorly in much of the north, resulting in low food availability for most seed-eating species.

The above photo is of a Common Redpoll, named for the red cap on its head, a regular irruptive species that usually comes south into southern Ontario and the northeastern states every couple of years. On their wintering grounds, redpolls feed primarily on the catkins of birch and alder trees. In a year of poor catkin production, redpolls will begin to move out of their regular range in search of an area with good food availability. In the south, this is often in the form of bird feeders. Redpolls love nyger seed (thistle seed), and will swarm nyger feeders in large numbers. They’re rarely seen in small numbers or individually, and flocks can reach 40 or 50, to upwards of 100 birds. This year is a bigger year for redpolls.

PISI1

Another frequently seen irruptive species is the Pine Siskin. This year they seem to have carried on through southern Ontario to places further south, but in some years they can be just as, or often more, numerous at the feeders than the redpolls. Siskins depend on evergreen cone seeds, but are also enthusiastic visitors to nyger seed feeders. Although they’re not very flashy, they can be distinguished from some other brown, streaky finches by their sharp, narrow beak (not well seen in this photo), and the yellow tints to their wing feathers.

Pine Grosbeaks and Bohemian Waxwings have also been reported in large numbers this winter. I haven’t had a chance to go out to look for either, yet, unfortunately. The last time I saw a Pine Grosbeak was some four or five years ago, and the only ones I’ve seen in Ontario were at the University of Guelph, back when I was a student there. They’ve been reported there again this year. That gives you an idea of the frequency of their irruptions this far south. I’ve never had the luck to see a Bohemian Waxwing, although I’ve gone looking for them.

RBNU4

These aren’t the only species that come south in years of low food availability. Red-breasted Nuthatches are seen periodically in larger numbers, and this year they moved out early in the fall, to destinations further south. My parents have one coming to their feeder this winter, however, and they’re usually gone by mid-fall. Black-capped Chickadees are usually year-round residents on their territories, but in years of good breeding success (that is, lots of babies!) coupled with poor winter food supply, large numbers of primarily young birds will move south looking for food. Chickadees moving through in the fall was slightly elevated this year, but 2005 was the biggest movement over the last few years. Blue Jays will also irrupt in larger numbers some years than others. We had a moderate movement this year, but the best year since I’ve been keeping track was probably 2003.

Northern Saw-whet Owl

Seed-eaters aren’t the only group of birds that undergo periodic irruptions. The seed shortages that cause birds to move also affect rodent populations in those areas, which depend heavily on seeds as their food source. In years of poor seed crops, rodent populations suffer sharp declines (often called “population crashes”). This year rodent populations had an especially severe crash, as last year’s seed crop had been good, encouraging a good breeding season this summer. That breeding success was followed by this fall’s seed shortage, causing a precipitous decline in numbers.

Birds that prey on rodents, such as owls, tend to follow their population cycles fairly closely. Because rodents were so abundant, owl populations, particularly the Northern Saw-whet Owl (pictured above), had a very successful breeding season. When rodent populations crashed this fall saw-whets began moving south in huge numbers. Saw-whets usually follow a four year cycle, where every fourth year their rodent prey, Red-backed Vole, peaks in number and so does their population. Saw-whets are naturally migratory and will move south every year, but the numbers encountered in the south vary according to the size of the movement. The combination of high saw-whet numbers due to this year’s breeding success and the low prey availability because of poor seed crops resulted in a larger-than-normal movement of saw-whets this fall.

GGOW

Great Gray Owls follow a similar pattern, although they usually only move as far as they need to to find food, which means they don’t often make it as far south as most human communities. A bird of northern Ontario, they often just move to another part of the north when prey shortages occur, since such shortages are often regional in nature, although small numbers are usually seen as far south as cottage country every winter. A few years ago, in the winter of 2004-5, a huge movement of these beautiful northern owls occurred in southern Ontario, and I had the opportunity to get out and see several. They’re the only ones I’ve seen.

Another species of owl that comes south every year, but can move in larger numbers some years, is Snowy Owl. There’s usually one bird that winters at Tommy Thompson Park (home of the research station, and as close to a backyard as I have here in the city) every year, although I haven’t seen reports of it this year. However, in years of larger movements, such as 2005-6, many Snowy Owls can be seen in a relatively small area (of suitable habitat, of course). The photo below was taken on Amherst Island, near Kingston, where we had up to 13 individuals during one day.

SNOW3