One thing I’ve pondered occasionally is what we would notice that we hadn’t thought about if we warped back a few centuries. One that’s always stood out to me is the sheer number of birds. What exists today is a fraction of their population before industrialization. And one mockingbird or crow means you can have a bad time in your back yard now… imagine 20 of them.
The first-ever comprehensive assessment of net population changes in the U.S. and Canada reveals across-the-board declines that scientists call “staggering.” All told, the North American bird population is down by 2.9 billion breeding adults, with devastating losses among birds in every biome. Forests alone have lost 1 billion birds. Grassland bird populations collectively have declined by 53%, or another 720 million birds.
Before West Nile Virus hit, there were an awful lot of crows in the Washington, DC, area. I saw a statement in the newspaper that a stand of trees at Rockville Pike and Randolph/Montrose Road was home to half a million crows. That seemed improbable on its face; but it you were on that stretch of Rockville Pike about dusk, and saw the stream of crows, it gained probability. But West Nile Virus more than decimated the crows, and that stand of trees is gone. The crows are making something of a comeback now, after maybe 15 years of invisibility.
