Sunday, December 19, 2010
I've been spending a lot of time out in the field, mostly because it is Christmas Bird Count season. Did the Beaver CBC yesterday, and the Columbus count today, with two or three yet to come.
During a trip to Big Island Wildlife Area last weekend, I ran into a cooperative little pack of one of the most interesting birds to grace our wintertime landscape, the American Tree Sparrow.
These tough little birds have come a long way; they nest in the tundra of the North Country, and the bird in my photo above may well have traveled 1,200 miles or more to be with us.
I wrote a cover story for Bird Watcher's Digest on tree sparrows for their winter 2009 edition, and it was a fun piece to write. The article was complimented by wonderful artwork by David Plank.
There are few birds that I admire more than American Tree Sparrows. For one, they are fun to watch. The flocks greatly enliven somber fields of goldenrods, their tinkling calls sounding like the shattering of distant icicles. These rusty-capped seed-eaters love the fruit of goldenrod, and dangle like feathered acrobats as they pull and pluck the seed heads.
But what impresses me the most about them as their ability to deal with COLD weather. Many is the time that I've watched flocks cavorting about fields, busily gorging on the seeds of various old field "weeds" on days so cold it hurts to breath. Watching them, I always think about their upcoming night. Clear starry winter evenings, when the temperatures plummet to 0 F or colder, and you've got no warm bungalow to repair to, makes for a long evening.
That's why tree sparrows really stoke the furnace with all of those seeds. An efficient forager can shovel in 6 grams of food a day - nearly one-third their weight! They need all of that energy to make it through the long winter nights.