As we start our daily walk, Dave and Clancy and I hear a crow calling from a tree in the woods. Its harsh and easily recognized caw-caw occurs throughout the year, including through the winter.
I don’t think we have any crows staking out territory on Owl Acres. We do have visitors quite often, though. We hear them throughout the year as they pass by.
Unlike most other birds, crows live in family groups from two to 15 birds. These family groups include a breeding pair and their offspring, sometimes several years old. Like in a human family, the older siblings help feed and care for the younger ones for two or three years before they venture out to find a breeding partner of their own. Each crow family has its own territory, which all members of the family help to defend from other crows. A new breeding pair has to have a territory, too before they can set up housekeeping. Sometimes the parents give them part of the parental territory, and sometimes they take over another family’s turf.
Along with the family groups, crows gather in communities to roost, and, especially in winter, they form flocks that forage together. We used to watch a cloud of crows lifting off from a communal roosting site in a Christmas tree farm. They were heading for town where they would find food in places like garbage cans and fast-food parking lots. Watching 250 crows descending in a cloud over the McDonalds parking lot, it’s easy to see why a group of these big black birds is called a murder of crows. Crows have adapted well to urban and suburban landscapes and have come to understand that garbage cans are excellent food sources.
The American crow (Corvus brachyrhynchos) is 16 to 21 inches long including its tail, with a wingspan of up to 40 inches. It weighs about a pound. It has strong legs and feet, a slightly rounded tail and stiff bristles over its nostrils. The crow is uniformly glossy black with a slightly iridescent sheen. The bill is also black and sturdy with a slight hook at the end. They’ll eat just about anything and can be very clever in getting at the food. One strategy these days is to poke a hole in a trash bag to inspect the contents and fish out whatever looks interesting. The results of that are often attributed to dogs or raccoons, but the crows may well be the culprits. In rural areas, crows will hunt frogs, small mammals and insects. They’re not averse to eating fresh roadkill either and are known to cooperate with other predators and carrion eaters to get their share.
Crows build their nests in trees and roost in trees, but they forage on the ground, hunting worms, insects, grain and whatever else they can find. Open grasslands and agricultural fields with nearby woods (like the cornfield across the fence from Owl Acres) are excellent habitats for them. So, it turns out, are cities and towns where food waste is plentiful and they are protected from being shot.
American crows are thought to be the most intelligent birds that frequent Owl Acres. They are related to ravens and rooks, jays and magpies. Some of their cousins have been observed fashioning tools such as hooks made from wire to get at food they can’t reach directly with their bills. American crows haven’t been documented doing this exactly, but they have clearly adapted to new habitats and environments as cities and farms have replaced their native woodland and prairies. American crows live up to 19 years in captivity and average around 14 years in the wild. They have plenty of time to learn and adapt. It’s uncommon for birds to actively care for their sick or injured members. Crows do, however. Researchers have observed healthy birds bringing food and feeding it to obviously sick or injured individuals.
Over the years people have tried to exterminate crows by shooting them on sight. They’re still around though and may be increasing in numbers as they adapt to new environments. They are protected by the Migratory Bird Treaty Act of 1918 and ten years ago, the North American crow population was estimated at 31 million. Fortunately, they’re not all on Owl Acres! We’ll welcome our visitors to the soundscape, and if they want to move in on a territory, that’s okay too.
Photo from Wikimedia.org by: Alexander Davronov. Alt text: Crows don’t get enough respect. So, here’s a painting of a noble crow, wings spread, standing in heroic profile before a rising full moon. Why not?