(too-loo-gak): Inuktitut (the language of Inuit) word meaning raven

Bob Bromley

Yellowknife, NT

There are lots of neat things about their legs and feet. They’re large. The raven is the largest perching bird, or Passeriformes, in North America. They look the same as songbirds generally, in general stature, they’re just scaled up. They have long bare legs. But they’re odd in that they’re an Arctic species. That’s not quite true. They have a huge distribution around the world. They’re one of the most successful species of birds. The neat thing about ravens is they’re the only bird that lives in the Arctic with long bare legs. You think they would freeze and fall off. Apparently the reason is they are a furnace. They have a very unusually high metabolic rate for heat production. Almost always the metabolic rate for feet is based on (mass and joints?). Ravens are the exception. They have a much higher metabolic rate heat production than they should have for their weight. That is the reason apparently that they retain their bare legs whereas all the other arctic species have feathers for heat conservation. They need to release heat in the summer and spring. It ends up in a lot of neat behaviour. We banded a bunch of ravens here in the 80s and early 90s. There are lots of stories about that. We’d try to go around and read leg bands all winter but we never could of course because their legs are then engulfed in their belly feathers. That’s one of the reasons they have these long belly feathers because they’re up quite a bit and they’re always sitting. It’s actually hard of make them stand up. They’ll wait to the last second and then they’ll fly.

The feet are tough and able to grasp things as scutes. It’s not as highly developed as the osprey foot, which is super developed that way. It almost has little barbs on each little bump. They’re very sharp. It’s for grasping and working with prey. And it has a massive beak, very strong. And they’re lightening fast. I had a scary experience. I was holding it loosely and I got busy recording data. Before I knew it, it dove at my eye. If I hadn’t been wearing these glasses, my eye would have been gone. I was weak-kneed about it. Shortly after that an article came out about farmers being compensated in Ontario. Apparently they would peck the eyes out of cows and sheep. Once that would happen they would die of shock or then go for the kidney. Pretty amazing bird. That was in the Globe and Mail.

They do have a lot of feathers. I’m not aware of any different layers. There’s the downy layer and then the top feathers and then of course the flight feathers are the large ones with a lot of structure. I don’t know of anything exceptional about their feathers.

To the best I know, they mate for life. I don’t think there’s any information about whether the young stick around but they take at least two years to mature. They have pink mouths for the first year and in the second year the tongue is pink and black and ion the third year it’s solid black which is how we age them.
I don’t know if that information is available (lifespan). They can live for well over 20 years but I don’t know what the average lifespan can be.

They have a huge vocabulary. I have a thesis from Alaska on that. I think they recorded over 80 calls. They also noticed there is a lot of regional dialects. It could be more than 80. There’s been a lot of work about what calls mean and what behaviour goes with calls and how they’re tied together. There’s a chirrup call that goes with the dropping of the belly feathers and the throat feathers and the raising of the horns. That’s an aggressive call to another raven.

Starting in the second week of January, we start seeing courtship. There’s a lot of flying together. There’s the upside down flight or the coupling flight. There’s courtship behaviour observed at any time of the year. There’s a lot of billing each other. You often see them sitting on telephone poles billing. A lot of flying displays together. It usually involves chasing away other makes. There are frequently three birds seen in early spring. Mating starts with courtship. Nest building starts in March in the Yellowknife areas. They’ll usually be laying eggs by late March or early April. Their eggs are smaller than chicken eggs. They’re splotchy and blue-grey with a little more green. They’re quite a complex colour, but they’ don’t stand out in the nest. There are usually five to seven. They’ll hatch in late April. There is a 23 day incubation period and it’s about five days before they fledge. The nests are amazing in terms of what they’ll gather. They like to have sparkly stuff. It’s pretty amazing. I’ve been in the field in remote situations and there will be tinfoil. They’ll nest with skulls or bones or whatever. Pieces of old canvas, newspaper.

There’s an increasing tradition of nesting in Yellowknife on human made structures. So now we know of 25 nests in town. They seem to return to the same nest every year.

It was mostly the power lines burning the birds. If they get to a yearling or a two year old they have a good survival rate after that.

We have had an exchange between Fort McMurray and here. We’ve each recovered two of the other’s banded ravens. It’s not a migration. It’s more of a nomadic move to find a mate or get kicked out and go get established somewhere.

I gather they’re sensitive to dead ravens. In the old days, I know pilots with their aircraft used to hang up a dead raven to keep them away otherwise nothing they did would work.

One March we were out skidooing and I found a raven in a leg hold trap. I went over and got it out and one half of its leg was frozen. I cut it off right at the joint. We noticed there was another raven making a lot of noise, flying around in the distance. In was early March or the end of February. These two birds got together in the air and did all kinds of incredible displays and calls. They were obviously a pair. A pretty tough bird. It didn’t appear to notice the loss of its leg.

They are hunters too. I have seen them catching lemmings, heard stories of them chasing ptarmigan.