Beluga (Delphinapterus leucas)

I was asked a while ago to do a post about beluga whales, so I thought today would be a good time to do it. My encounters with belugas have been limited to visits to the Vancouver Aquarium, but they were pretty cool. I remember we spent a week of school at the aquarium, and one of our assignments was to pick an animal at the aquarium and watch it for a while. I have no idea why we had to do this, but I have a distinct memory of picking the youngest beluga whale at the aquarium and trying to get it to come over by putting pictures of squid against the glass. I don’t think it worked.

Beluga whales are members of the family Monodontidae, with the only other animal in the family being the narwhal. They like the cold, living in arctic and and sub-arctic waters. You can see belugas pretty much anywhere in the Arctic Ocean; there are populations in Canada, Alaska, Russia, and Scandinavia. Many populations are migratory, moving to warmer coastal areas and rivers during the summer months.

Belugas gathered at an estuary in Hudson's Bay. They are social animals, and often congregate in large pods.

Belugas gathered at an estuary in Hudson’s Bay. They are social animals, and often congregate in large pods.

Belugas can get pretty big, with males growing up to 5.5 meters, and can weigh over 3500 pounds. I’m pretty sure belugas qualify as obese, because fifty percent of their body weight is fat. Their blubber is 10 centimetres thick. That’s a lot of fat. Belugas have a distinctive white colour, which camouflages them against the ice floes in the arctic. They are unique among whales, in that they shed their skin every year. In the winter the skin thickens and becomes yellowed, mainly around the back and fins. Presumably this is to protect the animal when it’s swimming under thick arctic ice – it’s probably pretty painful to constantly rub your back against ice floes.

A very recognizable feature of the beluga is its funnily shaped head, which is called the melon. The melon is a specialized organ composed of fat (like most of the beluga). But unlike the rest of beluga fat, the melon is composed of long-chain fatty acids, and is used for echolocation purposes. When the beluga emits sounds, the whale changes the shape of the melon by blowing air into its head. This helps focus the sounds, creating very effective echolocation, which is needed to navigate the treacherous ice sheets. It also allows these funny animals to produce a number of very loud calls that sound similar to bird song – hence one of their names, canaries of the sea.

A beluga whale blowing bubbles. Isn't it cute?

A beluga whale blowing bubbles. Isn’t it cute?

Belugas reach sexual maturity between four and nine years of age, and usually have a calf every three years. Calves are born dark grey and are about a meter and a half long. The skin colour of young belugas lightens with age, and they usually reach full whiteness at nine years of age. Nine years seems like a pretty late time to become fully adult, but there is evidence that belugas live a really long time. Biologists determine the age of belugas by looking at their teeth. Belugas lay down layers of dentin on a periodic basis, and by counting the layers one can calculate the age of the animal. Originally it was thought that belugas lived around 30 years, but it turns out scientists got the rate of dentin deposits wrong. Instead, it’s likely that belugas can live upwards of seventy years.

A baby beluga in the deep blue sea... actually, it's in an aquarium, but the idea is similar.

Baby beluga in the deep blue sea… actually, it’s in an aquarium, but the idea is similar.

I have fond memories of the belugas at the aquarium, and I still like these strange whales. Despite their silly appearance, these guys keep on smiling, and I like them for it.

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