(This 1027th Buffalo Sunday News column was first published on November 28, 2010.)
A number of early reports from regional feeders suggests that this winter may bring a flood of northern birds to this area. These periodic occurrences are called irruptions and birders look forward to such years, because they make winter birding exciting.
Many people are now reporting pine siskins visiting their feeders. Often associating with goldfinches, the siskins appear more sparrow-like. They are generally brown birds with noticeable streaking on their breasts. Unlike sparrows, however, they have very thin bills and male siskins show varying amounts of yellow in their wings and tails.
Siskins are another species I count among my favorites for, one autumn when I was a beginning birder, I found dozens of them in my suburban Rochester neighborhood. I couldn't believe that I was seeing so many of these birds that were entirely new to me. With some trepidation I approached one of my mentors, Howard Miller, to ask if I was really seeing these rare birds. "Oh, yes," Miller informed me, "we're having an incursion of siskins." Needless to say, I was delighted to have my tentative identification confirmed.
And now we have reports of two rare grosbeaks at feeders. A single pine grosbeak and four evening grosbeaks were recorded at separate feeders. Both species I consider spectacular finds.
In a lifetime of birding I have only seen pine grosbeaks four times and one of those times was in Canada 100 miles north of Toronto. But the best views I ever had of this species was south of Johnson City where I lived for a few years. For over a month a dozen of them fed in a grove of staghorn sumac where area birders could watch them from within a few feet. Like others among these northern invaders, they are unaccustomed to humans and pay little attention to us. To them we are no different from unthreatening deer feeding nearby.
I returned to that grove the next winter to look for these birds. No luck and friends tell me that they never have returned to that area.
Evening grosbeaks are another story. Through the 1970s they were common winter visitors to this region and during summers you could find them everywhere in the Adirondacks and Algonquin Park. In fact, many of those who maintained feeders complained about their voracious appetites for sunflower seeds. A group of them would clean out a feeding tray in an hour.
Since then, however, their population has crashed and they are rare even in northern forests. Thus their appearance at a feeder in Wilson is exciting news.
Evening grosbeaks always look to me like big muscular goldfinches. The males show quite a bit of yellow in their plumage but the females are more gray and white. They are twice the size of goldfinches and you cannot miss the huge pale bill they use to open those seeds. Gross is the German word for large and these birds are well named as grosbeaks.
The bill of the pine grosbeak does not appear nearly as large, perhaps because it is dark gray in color. The males appear to me as almost robin-sized pink and grey birds with white wingbars. The females don't show any pink.
It is easy, however, to confuse two of these northern visitors: the pine grosbeak and the white-winged crossbill. Crossbills are quite a bit smaller but the males are also reddish birds with white wingbars. Their strange crossed bills are not at all easy to detect. (They use them to pry apart pine cones to get at seeds.)
A few years ago we had a major incursion of these white-winged crossbills, but as yet this year I have seen no reports of them. Nor have I seen reports of the still rarer red crossbill, which is very similar to its white-winged cousin but lacks wingbars.
Two other northern species sometimes move south in numbers: redpolls and purple finches. But more common birds like red-breasted nuthatches and chickadees join the movements. Occasionally such irruptions also bring western species like Bohemian waxwings and varied thrushes to our region.
What causes these irruptions? You'll have to ask the birds. Two hypotheses: (1) poor northern seed crops and (2) an overabundance of individuals produced by an excellent breeding season.-- Gerry Rising
http://www.acsu.buffalo.edu/~insrisg/nature/
