Common Raven (Corvus corax)

I thought of blogging about the raven because the other day one of my friends asked me what the difference between a crow and a raven is. My response was: ‘ravens are bigger.’ While this is true, I figured I should probably do a little research and find out what the actual difference is. I knew the birds were different species, but what I didn’t know is that there are multiple species of crows and multiple species of ravens. As far as physical differences go, my answer was pretty spot on. Here’s a comparison:

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The raven is on the left, crow on the right

If there wasn’t such a vast difference in size, I wouldn’t be able to tell the two birds apart, especially if they were flying around. But ravens are generally much bigger than crows. In fact, they are one of the largest member of their family, Corvidae. The corvid family contains crows, ravens, jays, magpies, and many other birds. The family is well studied for its intelligence, and corvids are considered the most intelligent birds, and among the most intelligent animals.

Ravens, like many birds, are monogamous – they mate with the same partner every year. Adult ravens usually live in pairs, while juveniles are more likely to form flocks. Juveniles living in such flocks have been known to call other ravens to the carcass. The reason for this is unknown, though two explanations have been provided. One is that the young birds band together so adults cannot chase them away from the carcass. Another is that carcasses are generally too big for a few birds to fully use, so they call their compatriots to join in the feast.

The raven is an omnivore, utilizing many different food sources. This adaptability has led to the raven’s success. They will hunt small rodents, birds, and reptiles. Ravens are not afraid to eat carrion, and often eat roadkill, or wait by carcasses until larger animals tear them open. Or they will steal eggs and young from other birds’ nests. They also eat human waste, undigested food in animal feces, and plant material. As I said, they are omnivores. And they truly fit the bill. It seems they’ll eat anything.

Ravens, like most corvids, have a large variety of vocalizations they can produce. They are capable of mimicking human speech, as well as sounds from their environment. They use up to 30 different calls in wild, to communicate information about food sources, predators, and simply to socialize. When one of a raven pair loses its mate, the bird will reproduce the calls of its mate, to try and get the missing bird to return.

Now here’s the fun part about ravens. Their intelligence. Like I said before, ravens are really smart. And now I get to tell you all about their feats of intelligence, which hopefully will impress you. Ravens have brains that are one of the largest of all bird species. There is evidence that ravens preform many high level cognitive functions, including problem solving, insight and displacement.

Displacement describes the ability to communicate about an object that are distant in space or time from the time of communication. Juvenile ravens generally forage alone, but roost in flocks at night. If a young raven finds carrion guarded by tough adult ravens, he will fly home and tell the other ravens about it. The next day all the young ravens will fly to the carcass and chase off the adults. This behaviour has been described as displacement, and is used as evidence to show that ravens are one of only four known animals able to do this (bees, ants and humans being the others).

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A raven demonstrating its intelligence. In order to get the water, thirsty ravens must drop enough stones into the tube to raise the water level.

Ravens can also demonstrate problem-solving abilities. One experiment had a piece of meat tied to a perch with a string. In order to get the meat, the birds would have to pull the string with their beaks, while stepping on the already pulled up part to prevent the meat from falling back down. Four out of five ravens were able to eventually do this, with no trial-and-error learning. Pretty impressive, right?

Another things ravens do is cache food. They will bury choice morsels so that when they are hungry later, they can dig them up for a quick meal. However, ravens are so tricksy that they watch were other ravens bury their food and then raid the caches. As a result, most ravens will hide their food when no other ravens are present; if they see one they will fly to a distant location to cache the food. Other times birds will pretend to bury food to confuse watching ravens.

All in all, ravens (and other corvids) are fascinating animals. Look up any video on youtube of problem solving crows or ravens, and I guarantee you’ll be impressed. I’ve always been a fan of crows and ravens, but the more I learn about them, the more I admire them.

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