For the Birds Radio Program: Crows
Laura talks about the true harbingers of spring.
(Recording of a American Crow)
Lots of people have been calling and writing me about the most conspicuous bird of the Northland right now, the American Crow. Crows are all over the place, encouraging us to believe that winter must be almost over. Some pairs are checking out possible sites for nesting, but most of the crows are still in flocks, stirring up a ruckus not only whenever they spot an owl but also just for the heck of it.
Philip Soucheray of Bayfield sent me a lovely description of crows in springtime. He wrote: “The first sure sign of approaching spring for me has always been the increased activity of the crows. They have been waiting all winter in the great stand of virgin pine back of our place, but this past week has seen a lot of frenzied activity. Pairs of the huge black birds have been running off to their own tree tops. (Who can tell the ladies from the gentlemen crows - - who cares?)
“The calling back and forth seems to have taken on a much more urgent, almost frantic pattern. Crows have a code of format that is much like the usage pattern on marine radio. Their channel 16, the calling channel, is a single note, channel 1. For more urgent calls they use channel 2 or two blasts on their crow horn. When there is contact they shift to channels 3, 4, or 5. A three from one end of the area gets a three from a long way off and fives a three in response. This continues until someone on four lets his presence be known, and another four answers back. Sensing some action in the area, maybe a party, somebody on five puts out a five call looking for a personal response. Five seems to be the last available frequency, and hopefully the folks on two or three have made personal contact and met in their own trees somewhere by this time, thus opening up the air for others. Like the marine radio around cocktail hour, the air really starts to crackle.”
Dr. Soucheray continues: “Grandchildren are wonderfully intrigued by the ability of some of us to understand what the crows are saying. Or are the children just putting us on because they alone know what the birds are really saying?”
Dr. Soucheray points out an interesting phenomenon–the ability of birds in the crow family to count. Actually birds in a few other groups are also known to count. Both ravens and Gray Parrots have been taught to open a box which has the same number of spots on the lid as there are dots on a key card. Ravens don’t have any trouble doing it with numbers up to 6 or 7.
One jackdaw, a close relative in Europe of our American Crow, was taught to pick up unmarked box lids to look inside for little baits. Each box could have one or two baits or be empty, and the jackdaw had to open each box in succession until it had exactly five baits. If it opened too many or too few boxes, it received a light touch on the back with a mechanically operated stick. On one trial it opened the first box, got one bait, opened the second and got two, opened the third and got a fourth, and then went back to its perch. The experimenter was recording “one too few” when the jackdaw suddenly went back to the boxes of its own volition, bowed it’s head once at the first box where it had found one bait, twice at the second box where it had found two, and once at the third box. Then it opened the fourth box, which was empty, and the fifth box, where it found a fifth bait. Now it returned to its perch for good.
Yes, whether they’re yelling back and forth or doing tasks for experimenters, it’s certain that crows can count.
(Recording of a American Crow)