Sunday, January 4, 2009

Winter Sparrows

It's cold this morning. Near 70 yesterday and in the 20's this morning.

One of the special things about winter is the arrival of the winter sparrows. A few years ago I set myself the task of learning the LBJs and have become much better with my identification, although I am by no stretch an expert.

I consider the field sparrow one of my winter feeder favorites. A small sparrow, it has a wide-eyed look due to the distinctive eye ring. I usually have one or two that will come to the feeder each day; today I was excited to have three at one time searching the ground for the seed that I throw out each morning (not that there is much to search for--I am generous in the amount I throw on the ground.)

I decided to look up the species account for the field sparrow on Birds of North America online (http://bna.birds.cornell.edu/bna) and my first surprise was the range map. It showed Wichita Falls in the year-around area of the map. I know I have never seen nor heard a field sparrow in this area during the summer. I have an email out to Terry McKee from the North Texas Bird and Wildlife Club for clarification. She and her sister Debra Halter keep records for this area and publish the bird checklist.

Field sparrows live in much of the eastern United States and don't migrate much. They vacate the very northern portion of their range and their southern range moves south somewhat. Their range is contained within North America--unlike many of our migratory birds, they do not move south into Central or South America.

According to BNA, the field sparrow normally doesn't frequent areas inhabited by humans and is uncommon in the suburbs. I suppose that is why it causes comment when I mention them at my feeders. But I have an unruly yard, next to an unkempt lot near open area. Perhaps that is why I am so lucky.

As is true of many sparrows, they eat primarily grass seed, supplemented by insects in the breeding season. Field sparrows build their nests in tall grasses within a few feet of shrubby vegetation or in the crotches of shrubs or saplings. They may nest multiple times in a season, building a new nest each time. Only the female broods the eggs.

One interesting item I noted in the species account was a record of the field sparrow feigning a wing injury when a predator approached a nest. We think of this in the killdeer--I wonder how many other species of bird demonstrate this behavior?

Another interesting note in the account was that cowbird parasitism was not very successful. Although cowbirds did parasitize field sparrow nests, few of the cowbirds fledged (unfortunately, neither did the baby field sparrows.) Makes you wonder why cowbirds continue to try, doesn't it? It would seem at some point, this behavior would stop. But perhaps the cowbird can't differentiate between one little bird and another.

Good birding!

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