Book title: Crows: Encounters with the Wise Guys
Author: Candace Savage
Publisher: Greystone Books
Date: 2005
ISBN: 9782764604601
Length: 105 pages plus index and bibliography
Illustrations: many from different sources
Quote: "Any day with a crow in it is full of promise."
Some say crows' flight, or maybe that of ravens, rooks, or magpies, promises different things according to the number of crows flying toward you. (They must be approaching you, calling attention to themselves, for it to count.)
Although one reviewer described Crows as "over too soon," its focus on crows' intelligence suggests that Candace Savage wrote it as a spin-off or follow-up to Bird Brains. Along with many scientists, Savage was fascinated by the news that New Caledonian crows not only used hooked sticks to pick food out of crevices, but had learned how to make hooks at the ends of sticks--thus not only using tools, but making tools.
So far nobody has confirmed that North American crows are quite that clever. American crows have, however, been caught sharpening points at the ends of sticks to spear food, and several species of crows have been seen throwing hard-shelled nuts in front of cars so that the cars will crush the shells.
Crows are unusually social birds. Like little songbirds, they form big flocks in autumn and winter, but they live in extended families even during the breeding season. Some young crows, like some young humans, stay near their parents, taking some help from the parents toward their own support, giving some help when the parents are raising their younger siblings.
Ravens, which can be described as giant crows, get even more madly mixed reactions from humans than crows do. Ravens, it seems, have a taste for the meat of prey they can't kill or even tear open by themselves. They like fresh meat but sometimes, by the time they can dig into a piece of meat, it's not fresh any more. So they've developed an instinctive urge to watch others taste food first. According to Bernd Heinrich, ravens often offer unknown food to other ravens, or large animals, apparently to see how the "taster" may react. Stories of ravens who fed human fugitives for days probably happened more than once in human history.
However, the food ravens offer their friends isn't always good--hello, that's what the ravens are trying to find out!--and hungry ravens have been known to lead one large predatory animal to another, in hopes of a fight that will convert one of their friends into food for them.
According to Thomas Bugnyar, ravens can also tell deliberate nonverbal lies. Crows contains Bugnyar's account of how a raven, not as good a hunter as its companions, started misleading the dominant raven, and eventually lost all credibility in the lock.
Then there are studies of how crows and ravens talk to each other--in words. Humans hear their calls as harsh squawks, but the birds hear one another uttering different, distinct sounds. As the flock socialize together, their sounds seem to evolve into a simple spoken language, like those of parrots, cats, and dogs who live with humans. Only a few of these sounds, like the American crows' familiar alarm call, seem to have similar meanings for all crows. Flocks work out their own understanding of which of the noises they can make communicate affection, empathy, angry nagging, or what else.
One thing American crows communicate effectively is that they don't like humans much. Humans have chased crows away from food for a long time, and now humans who try to make friends with crows seem to be slowly, grudgingly rewarded with a reduction of dislike and distrust. Researcher Kevin McGowan, who spied on crows with binoculars and banded a few individual research subject, told Savage that all the crows in town hated him.
Crows contains the details of these stories, and more, plus lots of crow folktales and pictures. If you're fascinated by crows, or birds in general, or the alien intelligence of the other species that share our planet, you'll enjoy this book.
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