Hiking along the Temperance River on the North Shore in early November, I was looking for birds. Our list that weekend was miserably low. A yellowish-streaky bird with white wing bars flitted past me and landed in a nearby spruce. At last, I thought. A Goldfinch.
But as I raised my binoculars and studied it, I thought something was terribly wrong. Its beak…looked deformed. It took me several beats before I realized that I had not a goldfinch, but a White-winged Crossbill in my sight. I can be forgiven for this—in 50 years of birding, I’d only seen a handful of these elusive, boreal birds.
This year, the northern forests produced a bumper crop of seed cones, and also an intense spruce budworm outbreak—both food for finches and especially, crossbills. Hence, there was a bigger than average cohort of nestlings. By fall, they had exhausted the supply of seeds and were moving south, a natural phenomenon. The annual Wild River Audubon Christmas Bird Count recorded four of these species—siskins, common redpolls, purple finches and red-breasted nuthatches—but these are commonly seen on our counts.
This year, the northern forests produced a bumper crop of seed cones, and also an intense spruce budworm outbreak—both food for finches and especially, crossbills. Hence, there was a bigger than average cohort of nestlings. By fall, they had exhausted the supply of seeds and were moving south, a natural phenomenon. The annual Wild River Audubon Christmas Bird Count recorded four of these species—siskins, common redpolls, purple finches and red-breasted nuthatches—but these are commonly seen on our counts.
White-winged Crossbills are year-round inhabitants of coniferous forests. They usually frequent spruce fir woods, but are absent in pine forests, that their sibling species, Red Crossbills live in. They nest in spruce trees, often beginning in late-winter. Males alone care for fledged young, leaving females to mate and nest a second time—even in northern climes.
But in times of food stress, they leave their preferred habitat and might wander into weedy fields, or places of planted spruce trees, like old cemeteries, arboretums, and college campuses
Their unusual beaks are specialized to remove seeds from slender cones. Cornell University describes how they “grasp the cone with one foot and bite the cone where the scales meet, opening a gap between the scales, which can be widened with more action of the bill and by twisting the head. The seed can then be extracted using the tongue and upper mandible.”
Recently, the “Minnesota Birding” group on Facebook showed photos of dead white-winged crossbills that had been found on a gravel road near Aitkin. The poster speculated that they had died of starvation. But T. S. Roberts noted that the birds are drawn to salt—in his day, that meant moose licks; in ours, as Cornell noted, road salt might be mixed with de-icing chemicals that can poison the birds.
It’s sad to think of migrators coming all this way to be killed by modern standards of ice-free roads. We’ve got to do better as a society.
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