by Dr. Oakleigh Thorne, II
Corvids are the family of intelligent birds that include jays, crows, ravens, magpies, and nutcrackers. We have all of these in Boulder County. The Common Raven is the largest, followed by the American Crow. These two species have all black feathers. Both are very common in the Boulder area. Do you know the “caw-caw-caw” sound of a crow? Most kids do. The raven call sounds like a hoarse crow! You can tell a raven by its wedgeshaped tail when it is flying over you. They have long, pointed wings compared to a crow, which has shorter, more rounded wings.
We have several kinds of jays here: Blue Jay, Steller’s Jay, Western Scrub Jay, Grey Jay, and rarely, Pinyon Jay. The Grey Jay and the Clark’s Nutcracker are Corvids that you find only high up in the mountains, usually in the subalpine forests below timberline. They are grey, black, and white birds. Both of these are often nicknamed “camp robbers” because they are usually tame enough to steal part of a sandwich from your picnic table or even from your hand when you’re not looking!
We have the Black-billed Magpie in this area. They are truly a “Western” bird. They are black and white with a long tail. A flock of magpies can be rather noisy, especially when there is a group of young ones just out of the nest, begging their parents to feed them.
When I first came to Boulder 60 years ago, there were no Blue Jays…only Steller’s Jays. Blue Jays were an “Eastern” United States species. But they gradually worked their way west from town to town along the South Platte River and arrived in Boulder between 45 and 50 years ago. For a relatively short time they interbred with the Steller’s Jays and we had weird hybrids that looked (and even sounded) halfway between the two species. Then finally the Steller’s Jays seemed to retreat to the western edge of town and the pine/douglas-fir montane forests west of town, while the Blue Jays took over town and the ranches to the east.
In the 1990s, the Corvids were hit by the West Nile virus. It first showed up on the East Coast with lots of dead crows being found. When the virus (which is carried by a certain kind of mosquito) arrived in Boulder County, it hit the Blue Jays and the magpies particularly hard. At least that was my observation. I don’t see the big flocks of magpies that I used to see, and there do not seem to be as many Blue Jays in town as there once were. I will be interested to see if the Corvids build up an immunity to this virus in the years to come and can thereby restore their former numbers.
When I was a boy, I once rescued a baby crow that had fallen out of its nest and raised it as a pet. It was obviously a very smart bird. It learned to say “hello” and “boy oh boy,” and it also learned to laugh like a human, which was really funny.
There have been many studies done on the intelligence of ravens. I think that the Corvids in general are a fascinating group of birds in this respect. Maybe you can study them some day, even more than I have!!
Dr. Thorne is founder and honorary president of Thorne Ecological Institute in Boulder. They have helped “connect kids to nature” for more than 55 years. For more information about Thorne Natural Science School classes for children, check www.thornenature.org or e-mail info@thornenature.org or call (303) 499-3647.