While things look bleak for cod populations in the United States, particularly on Georges Bank and in the Gulf of Maine where late last month regulators slashed quotas for these beleaguered stocks, cod off of Norway and Russia are providing an encouraging example of the fish’s resilience when managed wisely.
As Reuters reports this week, fishermen in the far north are enjoying a boom in cod fishing where “the quota off northern Norway and Russia is a record 1.02 million metric tonnes, up a third from 2012 and six times as high as in 1990.”
The article credits both global warming for expanding the fish’s range northwards, but also the strict management of quotas issued from Oslo and Moscow.
Think that you could survive in the icy waters of the Arctic Ocean? Probably not, but beluga whales have certainly found a way.
The beluga whale, sometimes known as the white whale, is an unusual-looking marine mammal. A typical individual can be 13-20 feet long, and with its white coloring and distinctively lumpy head, the beluga is one of a kind. You can find belugas way up north in the waters of Canada, Alaska, Greenland, and Russia.
Beluga whales have many adaptations that allow them to live in extremely cold waters. They don’t have a dorsal fin, which is believed to help them survive under ice. They have round bodies and a thick layer of blubber to keep out the cold.
So what’s with that protruding lump on the beluga’s head? It’s called a melon, and other marine mammals like dolphins and porpoises have it too. It’s an organ with lots of oils and fats that is believed to be important during echolocation. The melon of a beluga whale is unique: by blowing air around its sinuses, a beluga whale can change the shape of its melon, which may be used in specialized under-ice echolocation.
The beluga whale is referred to as a sea canary, because of its high-pitched song. Individuals use squeaks, clucks and whistles to communicate with each other. Belugas are a very social species, and live together in groups called pods. When they move into bays, estuaries, and rivers during the summer they have been known to congregate in the thousands. Pods aren’t permanent though—belugas switch social groups frequently, sometimes moving hundreds of miles to join another group.
Beluga whales are smart and playful, and like to spit water at other whales or their keepers in aquariums. They’re the only whale species that’s commonly kept in aquariums, though captive breeding programs haven’t been successful.
Worldwide, beluga whales are ranked as near threatened by the IUCN. A subpopulation in the Cook Inlet in Alaska is listed as critically endangered. They suffer from pollution, especially in the rivers and estuaries they spend their summers in—there have been incidents of cancer in beluga whales linked to pollution in the St. Lawrence River. If we want these unique whales to be around in the future, we have to keep their environment safe and clean.