The intelligence of crows
Crows have been equally revered and reviled by humans throughout history.
There’s a reason crows have long been known as creatures of wisdom and were given respect by a number of ancient cultures. However, there’s an equal reason one of agriculture’s most famous mannequins is named the “scarecrow.” To be fair, scarecrows were put up in fields to frighten away an assortment of animal crop pests – not just crows – but the fact that crows were the animals whose name became attached to this famed farm-field protector shows this bird was high on the nuisance scale.
Missouri’s crow season, which started Nov. 1 and runs through March 3, is a tool that can be used to control the problems crows can cause for farmers. The fact that many states have crow hunting opportunities of some sort indicates that crow problems aren’t just a Missouri thing.
However, farmers also should remember that, each year, one family of crows consumes approximately 40,000 grubs, caterpillars, armyworms and other insects that can be troublesome for agricultural crops. Multiply that number by a flock of crows and that’s a whole lot of free pest control these birds provide to farmers.
Winter is when the American crow (also called the common crow) is more commonly seen in Missouri and elsewhere in its range because this is the time of year these birds tend to gather in flocks for foraging and safety benefits. Though it will be impossible for crows to ever completely rid themselves of their image as a farm nuisance, respect for these birds is increasing as humans learn more about their remarkable intelligence. Crows have the largest brains, in relationship to their size, of any species of bird and they demonstrate this increased cranial capacity in a number of ways.
For starters, if a group of crows near you appears to be talking about you, researchers say they might be. Crow communication is still being studied but it’s thought the intensity, rhythm, and duration of the sounds these birds make to each other is a type of “crow language” that communicate a variety of things – including messages about things around them.
Readers of Aesop’s Fables may recall the fable “The Crow and the Pitcher,” in which a crow uses stones to raise the level of water in a pitcher to quench its thirst. In an experiment with rooks – a European member of the crow family (both American crows and rooks are members of the genus Corvus) – the birds did exactly that: They dropped stones into a container to raise the water level so they could snatch a worm floating on top.
Crows have also been observed using sticks as spearing tools and bending wire into hook shapes and then using the hooks to grab items. Biologists have also recorded a number of instances in which crows seem to exhibit remarkable memory skills.
Another habit of crows that has drawn interest is their habit of gathering around a crow that has died. Sometimes these gatherings are relatively short, other times they last a day or more. Usually, the birds call back and forth during much of the time they are gathered around the dead crow. Though these gatherings have sometimes been referred to as “crow funerals,” it’s theorized that they are probably something closer to group learning sessions. It’s a type of “danger learning” where the living crows are observing the environment around their deceased comrade and trying to figure out what killed the bird so they can avoid that danger.
This is all theory, of course, but the remarkable details research has revealed about a crow’s intelligence makes one wonder how effective those scarecrows of bygone generations really were. Were flocks of crows really frightened by a scarecrow in a cornfield or, after a few flights over the field, were their caws simply verbalized amusement about our forefathers’ attempts at pest control?
More information about crows and other birds in Missouri can be found at mdc.mo.gov.
Francis Skalicky is the media specialist for the Missouri Department of Conservation’s Southwest Region. For more information about conservation issues, call 417-895-6880