By Mark Reese
Is it just me or are many of you noticing the resurgence of the American Crow around our neck of the woods? The crow is a common bird across North America but from the late 1980’s until recently the numbers have fallen quite dramatically with the major cause being West Nile Virus. Now, most folks would not mind seeing a decrease in these large black birds especially around newly planted sweet corn or corn that is ripe for harvest, but as a young boy I used to look up in the sky with wonder as hundreds of these birds would pass over in the evening on their way to roost.
As I said, they are common all across our country. They inhabit all types of land from fields to forests and have even adopted well to suburbs and cities. These birds are large- from 16 to 20 inches tall, most of it being a long tail. They generally weigh from 11to 21 ounces. Males are typically bigger than the females of the species. And they are highly intelligent animals. My grandmother told me of when she was younger she had one as a pet and taught it to talk as she did with parakeets and parrots. They can outwit many obstacles in their way when it comes to raiding your garden. The familiar “C-a-aw, C-a-aw, C-a-aw, is the sound we most often hear them make as they invade our home places.
They do like the presence of each other and routinely gather in communal nesting spots as evening approaches. The increase in trees and forests across the country has led to range expansions, particularly in the Midwest. Crows build bulky stick nests in trees and often form large families before the young strike out on their own at the age of two or three. All the birds are active feeders on most everything from seeds and plants to eggs, fish, mice, and frogs. They are definitely seen as scavengers around landfills.
They are susceptible to the West Nile Virus. This virus was accidentally introduced into the United States in 1999. It was originally a mosquito-borne African virus. With this arrival our population of crows has dropped as much as fifty percent. The virus can kill up to seventy percent in a single season. Being susceptible to the West Nile Virus makes these birds a bio- indicator of the spread of this disease across the ecosystem.
Much research lately has centered on the role of this virus in game bird populations as well as blue jays and other song birds. We are definitely seeing a decline in many species and this may well be the cause. Luckily, for the crow, some disease resistance is building up and the numbers of these birds have rebounded the last couple of years. Nationwide, their numbers are still holding up pretty good.
It makes me wonder just how much global warming has hastened the onslaught of many new environmental factors. Ticks are certainly more numerous, EHD has killed large numbers of deer in eastern Kentucky, and grouse numbers have plunged.
Like it or not, we must face up to the changes that a warming planet is bringing. I’ll leave it to the scientists to chart future happenings. It may be part of a natural cycle. It may be manmade. Or it could be a combination of both, but we certainly face some challenges.
Oftentimes they are troublesome, but it does me good to see crow numbers are on the rebound. It gives me hope that our earth and surrounding ecosystem can heal itself. For this reason we all should be thankful to see and hear these dark friends who remind us all that the earth is a fragile planet and must be revered by all.