As we enter the winter months in the Northern Hemisphere we kick off with a favorite of many, the Beluga whale. These Arctic dwelling whales live in some of the coldest waters on the planet and thrive. These ivory colored whales have many incredible adaptations to survive and thrive in our northernmost oceans.
Whale evolution stretches back nearly 50 million years to the Indian subcontinent. Scientists believe the Mesonychids, a hooved carnivore, began to migrate in the water. Eventually species split off and become water loving, and then water dependent. These were some of the earliest whales. It was roughly 30 million years ago when toothed and baleen whales split.
Belugas belong to the “super” Family Delphinoidae. Within this superfamily are 66 genera in 9 separate families. The species range from Killer Whales to the small Vaquita. Belugas belong to the Monodontidae family. This includes the Narwhal, their closest relative. The species name is Delphinapterus leucas.
The Beluga is thought to live up to 80 years, though there is some debate. It could be as short as 50 years. To survive in the Arctic, the Beluga has many interesting adaptations. First, their white color helps camouflage them in the polar ice. Their main predators include the polar bear and killer whales. Interestingly, the Beluga’s neck vertebrate are not fused, unlike most whales. This allows them to move their heads side to side and gives them a great range of motion. The Beluga has a blubber layer up to 5 inches (10 cm) thick, allowing them to survive in frigid waters. They also do not have a dorsal fin, unlike killer whales. This allows them to navigate around and under sea ice.
Belugas like most whales can only see in black and white. While they cannot smell, they can taste things in the water. Belugas can swim up to 6 mph (9 kph). They dive up to 750 meters deep and most dives can last 15 to 20 minutes.
Finally, the greatest adaptation of the Beluga is their large melon on their heads. This is a very important adaptation allowing the whales to echolocate. The whales can actually alter the shape of the melon through peripheral muscles, allowing the Beluga to focus the beams.
The World Wildlife Foundation has the Beluga as near threatened. There are only an estimated 136,000 mature adults left in the world. Climate change is the Belugas main threat. As well as oil and gas exploration and oceanic traffic.