Things that kill birds


As a nice follow-up to the hysteria that followed America’s collective realization that, sometimes, birds die in groups, the New York Times offers up a story detailing what actually does the killing. Some facts:

• Five billion birds die in the U.S. every year, out of an average yearly population of 10 billion, minimum. During fall migration, for instance, the population can temporarily rise to 20 billion.

• “Even without humans, tens of millions of birds would be lost each year to natural predators and natural accidents.” But we complicate matters. Often in surprising ways.

• For instance, rural domesticated cats in Wisconsin kill some 39 million birds every year, all on their own. That’s not even counting their city cousins, or cats in neighboring states.

• Window strikes kill more birds than pesticides, at least when measured directly. It’s hard to track indirect pesticide deaths, like chicks that die when their parent is killed by pesticide exposure. But, even if you assume an equal number of birds are killed indirectly as directly—i.e., double the number of pesticide deaths—it still doesn’t even get close to the worst years on record for window-strike deaths.
Not to say that pesticide deaths aren’t a problem—especially since the indirect deaths could be a lot bigger—but it’s interesting to see this cause of death in context with others. It suggests that, if you care about wildlife, you probably want to spend more time scrutinizing our propensity to build big, all-glass buildings. There’s an environmental issue here that’s going overlooked.*

Submitterated by TerribleNews.

*And in more ways than one. I won’t start ranting about energy use here, but, suffice to say, if someone shows you an all-glass building and tells you it’s sustainable or Green, feel free to roll your eyes. And maybe ask, “In comparison to what?”

Image: Fir0002/Flagstaffotos via GNU license

The last of a species, caught on film

As a kid, I was fascinated by the photos of the extinct quagga that were bolted to the sides of the zebra pen at the Topeka Zoo. I knew about extinction, of course. Dinosaurs were extinct. And I knew that buffalo had been shot by the 1000s a long time ago and might have become extinct, if they hadn’t been protected.

But I remember the quagga being a little shocking, nonetheless. Here was an animal, that had been alive recently enough to be photographed—not just drawn, like some imaginary beastie—but which no longer existed. Not even one. Not anywhere. It probably didn’t hurt that the quagga looked just different enough for little me to feel it as a loss. It wasn’t quite a horse. Not quite a zebra. And I would never see one, except as a photo.

It was a weird, existential sort of feeling, which I felt again while watching this video of a thylacine, also called Tasmanian tiger or Tasmanian wolf. This animal is actually a marsupial, not directly related to wolves (or big cats). Any similarity you see is purely convergent evolution at work—different species adapting to similar environmental niches. Not surprisingly, like the wild dogs they resemble, thylacines were hunted with abandon in the 19th and 20th centuries, because of the threat they posed to domesticated herd animals. The last confirmed* wild thylacine was killed in 1930. The last captive one died six years after that. That’s him, a male sometimes referred to as “Benjamin” in this video, shot in 1933.

Thanks to Waslijn for Submitterating!

*The possibility of living thylacines in the wild is a favorite topic of cryptozoologists. There have 3800 recorded sightings on since 1936. But nothing conclusive.