Common Ravens (Corvus corax) at Work – the World’s Smartest Birds?

Looking much like out-sized crows, to which they are related, Common Ravens are considered by many ornithologists (biologists who study birds) to be the most intelligent of the world’s 9,000+ bird species. People have apparently held this view from the earliest of times, as the folktales and legends of many races are filled with tales attributing great powers and cunning ways to these impressive birds.

We now have many indications of just how smart birds can be – a number use tools, and some have adjusted to changing conditions and have passed along their newly-acquired knowledge to other birds (more on that in future articles, but please write in if you’d like details). And, of course, parrot owners can fill volumes with tales of their birds’ learning abilities.

One of the most startling observations I’ve run across involved Ravens. One winter not long ago, people ice-fishing in northern Europe (I believe it was in Finland) began to find their hooks, devoid of bait and fish, lying on the ice near the hole that had been cut to allow access to the water below (fishing on an ice-covered lake during Finland’s winter is a cold business to say the least, so the lines were left untended while the fisherman wisely defrosted in nearby huts).

At first, neighboring fishermen were blamed, but some spying uncovered the real culprits. Ravens, apparently after watching people bait their hooks, learned to lift the lines with their beaks.

Keep in mind first that the birds had to associate the end of the line, now well below water, with food. The lines were quite long but, amazingly, the Ravens learned to stand on the slack each time it was laid down on the ice, so that it would not slide back into the water – and they figured this all out in the time that people were warming up and not watching!

The bait-thieves were likely helped in their efforts by the cooperative bond that develops between paired Ravens. Those observing the birds noted that one always kept watch while the other hauled up the line. As Ravens sometimes feed together, without posting a sentry, one is tempted to wonder – did they “know” to expect trouble?!

I once kept an injured Fish Crow (Corvus ossifragus), relative of the Raven, for a time. The bird took all of 20 minutes to learn how to open the latch on his cage’s door. Once I secured the latch with a lock, he would check the lock (once only) by rattling it, and no longer bothered with the latch itself. When I purposely left the lock unfastened, he immediately flipped it off and then lifted the latch.

Parrot owners are always great resources when it comes to “smart bird” stories.

You can learn a great deal about Raven natural history at:
http://www.birds.cornell.edu/AllAboutBirds/BirdGuide/Common_Raven_dtl.html

Image referenced from Wikipedia, uploaded by Franco Atirador in Feb. 2007, and using the GNU Free Documentation License. http://en.wikipedia.org/wiki/Image:Raven_croak.jpg