Whale of the Month - Bowhead Whale
The whale of the month for June is the bowhead whale, a baleen whale living almost exclusively in arctic and subarctic waters. This whale can be found at the 11th stop in our audio-guide. The bowhead whale gets its name from the size and shape of it's skull – their bow-shaped head is unique and represents roughly one third of their entire body length!
Bowhead whales average between 16-20 meters in length and 75-100 tons in weight, with females being slightly larger than males. They have a dark body with a light chin, and unlike most cetaceans they do not have a dorsal fin as they spend much of their time in icy waters. They use their size to their advantage when the sea freezes over and are able to break through ice that is at least 18 cm thick. They have adapted well to life in the arctic, and have a layer of blubber that can be up to 48cm thick.
Despite being large in size and living in what we would consider an extreme climate, bowheads can live a very long time. Based on scientific analysis of eye tissue and harpoon tips found in the blubber of these whales it's thought that they could easily reach at least 200 years of age. Like all baleen whales, bowheads are filter feeders, and consume a diet of marine invertebrates, crustaceans, copepods, and small fish. They have the longest baleen plates of all whales which is good, since they need an estimated 100 metric tons of food each year.
Vocalization is an important part of a bowhead whale's life and is used to find food and navigate migration routes. A fascinating project that took place from 2010-2014 off the coast of Greenland recorded 184 distinct songs from an estimated population of 300 bowheads. The songs changed between seasons and individuals. You can listen to some of these songs at the bottom of this post.
The bowhead is not known as a deep diver, but they can reach depths of 150 meters. Their average dive is 9-18 minutes long but can be up to 1 hour. They are usually found alone or in small pods of up to 6 individuals, though mother and calf pairs will migrate separately from male groups and remain separated during the summer months while the calves are feeding. Calves stay with their mothers for roughly one year and a female will have a calf every 3-4 years.
Historically, the bowhead whale was hunted commercially from the 1800's to the early 1900's. They were a prized target as they had lots of valuable oil and baleen and are very slow swimmers. Whaling devastated the global population. It is thought that by the time commercial whaling of bowheads ended in 1921, there were fewer than 3,000 left. They have been making a comeback, with some populations doing better than others. It is estimated that there are between 10,000 and 50,000 individuals today.
Like many cetaceans, the bowhead faces a variety of threats. These threats include ship strikes, entanglement in fishing nets and equipment, noise and chemical pollution, climate change, offshore oil and gas work, and the occasional attack from killer whales. Some Inuit populations have permission to hunt a small number of bowhead whales each year.
The bowhead whale can occasionally be seen off the northern coast of Iceland, which is at the southern edge of their usual range. The Icelandic name for bowhead whales is norðhvalur, which means 'north whale'.
You can read more about bowhead whales and their exfoliating behaviors here, and listen to a recording of their songs below!