Window on Nature
By Lowell & Kaye Christie, F47246
December 2005
For many years, birds have been getting a bad rap. It’s been a common misperception that birds are not nearly as intelligent as other creatures. If someone were to call you a birdbrain, you probably wouldn’t take that as a compliment. It’s thought that, since bigger brains are better at adapting to new surroundings, smaller-brained species must be stupid. Well, if that were true, elephants and whales would be the Einsteins of the animal world and far brighter than humans.
A team of brain experts living in several different countries decided to find out how intelligent birds really are. They had an excellent source of information “” observations by birders around the world. They also gathered statistics on the brain mass of more than 2,000 bird species. Putting the whole thing together required considerable human brainpower, but it produced very interesting results.
The scientists reported they now have proof that the phrase “dumb bird” needs to be deleted from our vocabulary. They found that the size of the creature’s brain relative to its body determines intelligence.
The smartest birds are corvids “” crows, ravens, magpies, and jays. Their brains may be walnut-size or smaller, but when compared to their total body mass, corvids stand tall. Next come hawks, woodpeckers, and then herons. The real dummies on the bird IQ scale are partridges, quail, and ostriches. Oddly enough, parrots score average on intelligence, despite being able to mimic human words and having large brains. Thus, more than brain size determines a bird’s intelligence.
We’ve read several times about how British blue and great tits, tiny songbirds related to chickadees, learned to peck holes in the tops of milk bottles way back when milk was delivered to your door. This was before plastic bottle caps came into use, so the birds only had to peck through a foil covering to get a sip of fresh cream or milk.
Several decades later, Japanese crows began displaying their own smarts. This particular activity took place at a traffic light on a university campus. When humans lined up waiting for the light to change so they could cross the street, the crows figured out how to use the stop-and-go traffic flow to their advantage. When the light changed color and humans stepped into the street, the crows hopped in front of the stopped cars and dropped walnuts picked from nearby trees. When the signal cycled to red for the pedestrians, the birds flew to nearby perches to wait for the vehicles to drive over the nuts and crack them open. Only after the signal stopped another group of vehicles did the crows swoop down to claim their meal.
Every once in awhile, the cars missed the nuts, but the crows persevered. They simply hopped back out and moved the walnuts in front of the tires; or they perched in a place where power lines crossed over the road so they could drop the nuts in front of the vehicles.
These crows have been playing the walnut/auto game for more than 15 years. But California crows have been seen doing much the same thing “” and, no, they didn’t travel to the Far East to learn the procedure. The California crows drop clams on the beach to crack their shells and then return to peck out the meat. Sadly, the same method doesn’t work for walnuts.
Scientists continue to argue whether actions like those above show genuine intelligence. But gradually they are accepting the fact that such crows either have insight or learn by following the example of other birds. Either way, a pretty sophisticated ability to solve problems is involved.
Here’s an example of another corvid, this time the Clarke’s nutcracker, which may have the keenest memory in the animal world. A nutcracker living in the northern part of the United States gathered some 30,000 pine seeds during a three-week period and stashed them in a 200-square-mile area. Then it spent the next eight months retrieving more than 90 percent of those seeds, even during the winter when they were covered by several feet of snow.
Another crow species living on an island in the South Pacific is known to make and use tools. These crows use their beaks as scissors to break and shape forked twigs into a tool that lets them fish bugs out of cracks and crevices. After going to all that effort, these crows don’t toss away their tool after they’ve eaten their fill. They carry it along to use in the next foraging spot.
Ravens hang around with their relatives and roost in the same tree overnight. This behavior can benefit the entire flock. Whenever one raven spots a large, dead animal, such as a moose or deer, it somehow reports that fact to the rest of the group when they gather that night. The next morning the entire group follows the finder to the carcass.
Why would ravens share such information? Consider the fact that finding a carcass isn’t a regular event, and it doesn’t happen in a particular place. Thus, when a carcass is located, the ravens pool their information. After all, meat doesn’t last forever. If other scavengers find it or it begins to spoil, none of the birds would benefit.
Finally, a personal anecdote: Recently we were talking to a friend of ours about what we had learned about Japanese crows. When she heard the story about the birds dropping nuts in front of vehicles, she said: “So that’s what they’re doing “” I see it all the time in my yard! These birds, crows and ravens, sort of roll the nuts into the road. I’ve been driving around them. We live on eight acres, so seeing them in operation was something we dismissed simply as play. I guess I’d better quit avoiding the nuts, and begin breaking the shells as I drive.”