The Urban Pantheist

Through the front window of the bus we took from Poole to Heathrow. The bus driver said he feeds this crow, and it was looking for its handout. I did a very poor job of birding in Great Britain this time. This is Corvus corone, I assume?

I need to make good on a promise. I said I would post about corvids in exchange for a bowling for rhinos donation, months ago. I've been waiting to either get a great picture, or have some kind of divine insight.

I have said before that crows are my favorite urban animal. I used to watch them whenever I could, as they picked at carrion on the roadside or at insects in the crop fields at Drumlin Farm. There was even a crow roost, a nighttime gathering, that met in the trees near my house in Brighton. Thousands of birds would collect at dusk in the fall. They would chatter and caw all night, maybe not having conversations, but definitely learning about one another. The cleverest of them would notice who was most well-fed, and make a note to follow that one in the morning, to find a plump carcass or other food source.

At Drumlin farm, wild crows would wait over our heads as we brought buckets of compost (which contained dead mice and other meaty morsels from the live animal center) up to the pile in the woods. They came to recognize the buckets, anticipate the time, possibly even recognize the humans involved. They definitely recognized my boss' car, probably by sound first, then by sight. She would throw the wild crows handfuls of dry dog food in the morning. The wild crows gathered around the cage of our exhibit crow. They would caw to one another from either side of the mesh. Our captive crow would pass items of food from his dish to the mouths of the crows outside. He had joined their flock, even though he couldn't fly with them.

If I hear crow call, I look to see what's happening. They call to one another, and their calls all have meaning. I've never decoded completely, but if you pay attention you can hear the calls and responses in different situations. The most obvious calls are the braying hysterical caws at the high end of their voice, when a predator is in their midst. They will gladly join a red-tailed hawk in aerial battle. These hawks, like crows themselves, prey on baby birds still in the nest, and I have seen an adult crow brought down to be a red-tail meal. Once, at my in-laws house in Vermont I drank coffee on the back patio and listened to some upset crows. Through my binoculars I could see a family of black bears climbing a tree a short distance away. I don't know if the crows were in any immediate danger, but they let everyone in earshot know that a potential nest predator was in a tree.

Then in 2003 West Nile Virus swept through the area. In Boston and at Drumlin Farm, where I would routinely see groups of 5 to ten crows on any summer day, I stopped seeing them altogether. Mosquitoes could bite a bird like a robin, which may carry the disease without getting sick, and then pass it to a crow with a bite. Crows and their smaller cousins the blue jays disappeared for a while; other birds at risk included owls and eagles (our captive golden eagle at Drumlin died of WNV). The zoos began innoculating entire flamingo flocks and other birds on outdoor exhibit.

And the crows have begun to bounce back. There had to be some number of birds naturally resistant to the virus, and they passed on the resistance to their chicks. Corvids are some of the most adaptable birds in the world, and they tend to do very well around the edges of human activity. While I haven't seen the huge numbers of crows that I saw 10 years ago, they do appear to be back in force. At the zoo I see groups of 5 to 10 in open areas and up in the trees barking at the red-tailed hawks (both crows and red-tailed hawks nest in the zoo). The West Nile Virus event is probably a minor hiccup in the in the long history of crows, and the history that humans and crows share with one another.

I've posted about corvids a few times before:
365 urban species entries:
American crow
Northwestern crow
Blue Jay

Ravens are rare in Massachusetts. We did take a special trip to find the one place in Boston I know of, where ravens nest. Here it is. I was not able to photograph a raven there.
Wild corvids seem to be camera shy. They are smart and aware, so when a big predator stops and trains its one huge eye at them, they know not to stick around. I didn't get any pictures of ravens in Greenland or Iceland even though they were very common in both places.

Here's a couple cute videos of a captive crow at Drumlin.

A Canadian documentary team just produced a film called "A Murder of Crows," about crows in general and about a sanctioned crow massacre in Ontario in particular. It's showing on CBC tomorrow night. Those of us in the states may have to wait for the DVD.

This crow was kept illegally as a pet, and confiscated and brought to a wildlife rehabilitator. The rehabber decided the bird was too imprinted to be released and placed it at the educational center where I work. We are trying to get it to the point where teachers can bring it to schools and such, and use it in educational programs. Its flight feathers are damaged, so it can't fly well, but once it molts it will. I brought it into our office for some exercise and "play time."

photo by cottonmanifesto
Urban species # 053: American crow Corvus brachyrhynchos

The crow has a long and storied association with humans. The crow's
black plumage and taste for carrion, along with its legendary
cleverness, has meant that crows and ravens have been taken to be
dieties, avatars, omens, and demons. What they are, truly, are the
largest members of the songbird order. They are thought to be some of
the smartest and most adaptable birds. Recently,
one captive crow became the first non-human animal to craft a tool
using man-made materials.

"True" crows are birds in the genus Corvus which includes birds
given the common name jackdaw and raven, all of which are omnivorous,
pigeon-sized or larger, and black. The crow family, Corvidae,
includes many other birds, including blue jays and
magpies. A great many of these bird species are bold and resourceful,
making them good candidates for urban species.

American crows are the most common crows in North America, followed by
the common raven (C. corax), which is found throughout Eurasia
as well. Ravens are absent from southern New England, and much of the
plains states and provinces, but are urban animals in such cities as
San Francisco. Fish crows (C. ossifragus) are found all along
the east coast, feeding along salt and fresh water shores. Fish crows
can be reliably distinguished from American crows only by their voice
(fish crows have a more nasal caw).

Carrion feeding animals of all kinds have learned to appreciate the
highways as a source of food. Other human-derived sources of food for
crows include garbage dumps, gut piles left by hunters, and (though it
is gruesome, it is historically significant) battlefields. Crows
famously visit crop fields, notably grapes and corn, but the fact that
they prey on insect and rodent pests mitigates their own pest status.

Crows are drawn near cities in the fall and winter in huge numbers,
known as winter roosts. Thousands of birds gather in large trees just
outside of city centers. These groups derive safety in numbers, as
well as safety from city-shy predators, such as great horned owls.
The radiating warmth of the asphalt probably helps to attract crows to
metropolitan roosts.

West Nile virus had a huge impact on crows over the past five years. We observed a crash in the Boston area crow population in 2002. We have seen more crows this year than last year, but there are still far fewer around than there were in 2001.


( Another crow )