Species in Peril:
Bowhead Whale
Bowhead Whale
Long living whales
Of all large whales, bowhead whales have the biggest head, thickest fat, and longest life span. These giants spent their entire time in the northest place on earth and it is not easy to find many species adapted to ice better than them. Away from humans, the population size of bowhead whales has been steadily increasing for years after the prohibition of commercial huntings. But with the reduction of sea ice, their habitat is becoming more accessible for humans and there are more threats coming along.
The True “Icebreaker” of the Oceans
Named after their unique appearance, bowhead whales have a huge head with curved mouth line which shapes like an archer’s bow. Even though bowhead whales are not the largest whale species, they may have the largest head in the world which measured one third of its body length. Their immense heads might make them look clumsy, but they are definitely not useless. Swimming under the sea ice, bowhead whales are able to use their tough skulls to break through 2 feet of ice. Unlike other whales, bowhead whales don’t have a dorsal fin or even a ridge for scientists to recognize individuals. But as the injuries from ice breaking or the attacks from enemies are not avoidable, scientists use scars on their heads as identifying features.
Life on the Polar of Earth
Bowhead whales are the only baleen whales spending their entire life in the Arctic sea, therefore, their features and behaviors are highly adapted to life in freezing water. In order to keep warm, bowhead whales have blubber layers which are over half a meter thick. And their smooth back and the ability to break ice also make it convenient for living under ice. To save energy, bowheads never rush. They move slowly and have a super long life span. It is estimated that the bowhead whales can live up to 200 years! Some people believe that the secret behind bowhead whale’s longevity is the cold water which allows them to maintain a low metabolic rate. And the explanation from the genetics says that they may have unusually vigorous DNA repair processes.
Facing many challenges in the Future
For centuries, bowhead whales were hunted commercially for their fat, baleen or bones. Due to the large profits of whaling, in the early 1900s, the bowhead whales population was reduced to the point of extinction.
Lucky for this species, in the 1930s, commercial whaling for bowheads was prohibited under international conventions. And since then, the number of bowhead whales has been steadily going back. However, this species is facing a new threat—global warming. Though all species including humans need to confront climate change, as an ice-adapted species, the reduction of sea ice may have a larger impact. With the diminishing of ice cover, the record shows that the bowhead whale population is moving further north.
Scientists predict that they may move around 250 kilometers further north in the summer by 2100 but no one knows if there is a limit that the distribution of their food source, zooplankton, can move to the north.
A Few More Facts about Bowhead Whale
- The baby bowhead whales weigh about 1000 kg at birth.
- Bowhead whales’ baleen can grow up to 4 meters long, they use their baleen to filter water and get feeded by krill, copepods and zooplankton.
- Bowhead whales have huge vocals and they sing songs to communicate with each other.
- There is one male bowhead whale estimated to be 211 years old when it was killed by hunters.
- 12% of bowhead whales have scars from boat gear.
Species Name
Balaena Mysticetus
Estimated Population
10,000 globally
Conservation Status
Vulnerable
Range
Canada, Greenland and Russia. Norway and Alaska
Reasons for Population Decline
Oil and gas exploration activities
Climate change
Shipping lane and ship collisions
