Monday, February 12, 2018

uber-petite & golden

This one is a winged miracle.

On our list of birds that only send their winters in the Tennessee Valley is the uber-petite golden-crowned kinglet. At only 5 grams (the weight of two pennies) they are the smallest perching songbird. The only thing smaller is a hummingbird which is not considered a songbird. They are a miracle unto themselves.

How golden-crowns even survive the winter is a mystery. Hummingbirds migrate to Central America: Costa Rica, Belize, Guatemala the
se kinds of tropical places. The tiny kinglet migrates but not that far. Many are here in the trees around us. And we have had two super Artic-like cold spells. It is estimated that up to 87 percent of all golden-crowned kinglets die each winter so there may be none left at the nature center to return north in spring.

It is simply too difficult for a bird this tiny to maintain internal body heat over a long cold night. So how does the golden-crowned kinglet even survive as a species with such a high winter time mortality rate?

Come spring, when they migrate back to their breeding grounds, they are baby makers. Petite little dynamos. Each mated pair can produce two broods of up to nine nestlings each, arranged in two layers in their small nests. Yes, perhaps raising as many as 18 young ones in only a few months.

Somewhat surprising to me. We found three at my Bird-About Birdwatching for Beginners program last Saturday morning. Tough little things.

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