Irruption

Last week, a large flock of white birds alit across the road from my house, each bird like a single feather, circling slowly down on a coil of unseen currents in the air.  A small temporary lake of snowmelt in the empty cornfield was their resting place.  Once they were all down, to an undiscerning eye they simply looked like stubborn patches of snow in last year’s furrows.  Their thick bodies and long necks were impossibly white against the dark soil. They were tundra swans, migrating, to my delight, from my old stomping grounds:  the marshes of the Mid-Atlantic. Each spring, 70,000 of these swans travel 2,000 miles to their breeding grounds in the tundra of Canada and Alaska. They stop just twice on their route, always in the same places: once in eastern Pennsylvania, and once in the Great Lakes.  If you live in Wisconsin, every year you can count on tundra swans to signal spring, and then, on their return route, to bring winter back again. 

            

But last week we were thrown off course--not by the ice and snow and below-average temperatures--but because my husband turned to look at the bird feeders that hang from our porch and saw what looked like parakeets:  four finch-sized birds, two of them with orange rumps and breasts and caps, the other two olive-green, all with dark wings.  One hung upside down and stuck its pink tongue out.

Photographs revealed the birds’ curious bills, which overlapped at the tip.  They were not parakeets but Red Crossbills, a non-migratory bird that breeds in the coniferous forests of very far northern Wisconsin and Canada.   Although they are a fairly common bird, Red Crossbills are not a local resident.  They were with us only for a morning, busily eating sunflower seeds beneath our large, old white pines, which I imagine must have looked to them from above, in the farm fields of central Wisconsin, a little bit like home.

What we had witnessed was likely part of an irruption—that’s irruption with an ‘i” not an “e”:  a dramatic, irregular migration of large numbers of birds to areas where they are not typically found.  Irruptions occur due to poor food sources.  In my Audubon guide, a map shows that Red Crossbills can irrupt across almost the entire eastern half of the United States.

I had not heard this word before, and I like it very much:  the idea that animals can irrupt, can break or burst in, enter forcibly or suddenly, as if they had something important to tell, doing what they want despite our human notion of balance and regularity.   I will watch for irruptions now, for unplanned things, as closely as I watch for each season’s parade of long-time friends.