Thursday, January 06, 2011

Blackbirds Deaths and Reality

While the Arkansas blackbird tragedy is an unusual and sad story, what isn't unusual is that blackbirds and other songbirds die from a wide array of human activities. Reading comments on several websites, many people seem to actually want the blackbird deaths to be some kind of wackadoodle government conspiracy, but this draws attention away from real and serious threats that imperil our native songbirds; they perish by the hundreds of millions each year, primarily due to habitat loss. Window collisions account for over 500 million songbird deaths annually, but there are many other causes.

"But they're being found dead out in the open!" Birds do not always instantly die from injuries caused from flight collisions. A bone fracture might prove to be fatal minutes after impact, which is not uncommon when birds hit a window. Birds also fatally collide with power and telephone lines, which is why you might find them in the road. After an impact, an injured bird might have just enough strength left to fly for cover in nearby shrubs, hidden from view, only to die later from internal injuries. Because of this, you might find a dead songbird in the middle of your yard or in the street where there isn't an obvious structure it might have collided with.

The 5,000 or so dead Arkansas blackbirds were likely a small percentage of the roosting flock. During spring migration, it’s not uncommon to find tens of thousands of blackbirds in large flocks at Nine Springs in Madison. One birder I know once reported observing over 100,000 blackbirds there a few years ago. Imagine if that many birds panicked during the night and took off all at once. Would 5,000 impact deaths seem so implausible? Sad, but not serious: 5,000 Red-winged Blackbird deaths (about .0025% of their North American Population). Sad, and serious: 3 Whooping Crane deaths (about 3% of the Eastern Migratory Population).

That people were initially worried is probably justified, provided their concern was for the safety and health of our nation's wildlife and ecosystems. On the other hand, I can't help but feel that other individuals, behind their accusations of government conspiracies and apocalyptic plagues, are more worried about themselves.

Link: Why are birds falling from the skies?

Red-winged Blackbird © 2011 Mike McDowell

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