What is taxonomy?
Bowhead whales are found only in the Northern Hemisphere, in Arctic waters. They are large, rotund black whales, with enormous heads that are about 1/3 of the total body length of adult whales. Bowhead whales used to be referred to as Greenland whales and sometimes even Greenland right whales. They are difficult to study because they live in the Arctic and spend a great deal of time under ice and water. The bowhead whale stock that occurs around Alaska is one of the most heavily studied of any large whale species. Bowhead whales are listed as endangered on the U.S. List of Endangered and Threatened Wildlife.
- Bowhead whales were hunted by commercial whalers for over four centuries, beginning in the North Atlantic in the 1500s and ending in the North Pacific by the mid-1900s.
- Bowhead whales have the longest baleen of all the mysticete whales with a maximum length of 13.1 feet (4 meters).
- Bowhead whales accumulate scars on their bodies from their encounters with ice. Scientists use these marks to identify individual whales.
- Bowhead whales are capable of breaking through sea ice at least 7.9 inches (20 centimeters) thick; some Eskimo hunters have reported whales surfacing through 2 feet (60 centimeters) of thick ice.
- Bowhead whales can spend a great deal of time under ice, it is still unknown how the whales find their next breathing holes
What should I know about bowhead whales?
- Where do bowhead whales live?
- How many bowhead whales are there?
- How can I identify a bowhead whale?
- How well can a bowhead whale see or hear?
- What do bowhead whales eat?
- How do bowhead whales have their young?
- How long do bowhead whales live? How do they die?
- Where can I find more information about bowhead whales?
Bowhead whales live in the Northern Hemisphere, around pack ice, often in shallow waters. Stocks of bowhead whales are known to occur: (1) North of Europe, (2) between Canada and Greenland, (3) in Hudson Bay area, (4) the Okhotsk Sea, and (5) the Bering, Chukchi, and Beaufort seas. Bowhead whales migrate seasonally within these waters, between summer feeding areas and wintering areas.
Bowhead whales are an endangered species. The western Arctic stock (Bering-Chukchi-Beaufort seas) is the largest population of bowhead whales. You can read more about bowhead whale stocks in the NMFS Alaska and Atlantic stock assessment reports.
They are up to 65 feet (19.8 meters) long. Bowheads have extremely large heads and relatively stocky (short and fat) bodies, highly arched jaws (a narrow upper jaw and a large, lower jaw), two blow holes, and no dorsal ridge or fin.
It is thought that baleen whales (including bowhead whales) probably have excellent hearing, which is valuable in the dark ocean environment where vision is less useful. Low-frequency sound can travel great distances under water, which is great for bowhead whales since scientists believe the whales' ears are designed for low-frequency hearing.
Bowhead whales are highly vocal and have a large repertoire of calls and songs. The echoes of these calls may be used to help the whales navigate through the ice as they migrate.
As bowheads are baleen whales, they filter their food through their long baleen plates. Bowhead whales open their great mouths and graze along the surface, in the water column, or on the sea floor. Bowheads mostly eat zooplankton including copepods and small shrimp-like animals called euphausiids (most are only 1-3 mm long). Scientists estimate that a bowhead whale needs to eat about 100 metric tons of crustaceans per year.
Most female bowhead whales are sexually mature by the time they reach a length of 45.9 feet (14 meters). Length of sexual maturity in males is not well documented. Mating behavior has been observed year-round, though most conceptions are believed to occur during late winter or spring. Females are pregnant for at least 12 months and pregnancies occur approximately every three to seven years. Most calves are born between April and early June during the spring migration. Calves are born able to swim. A mother and calf form a very close attachment. The calf spends most of its time swimming close to its mother and is carried in the mother's slip stream.
Bowhead whales' limited population and harsh aquatic home make bowhead whales the most difficult of all large whales to study. Because of an absence of teeth (which can be used to estimate age in other mammals), it is difficult to tell how old bowhead whales are when they die. Based on the recovery of stone harpoon tips, it is believed that bowhead whales live well past 70 years old. Recent studies, using tissues from bowhead whale eyes, suggest that these whales may live over 100 years.
Bowhead whales were commercially hunted for oil, meat, and apparel materials (corset stays, umbrella ribs, buggy whips, and more) from the 17th through the early 20th century. Today some Native Alaskans are allowed to hunt a limited number of bowhead whales for subsistence and products to produce native handicrafts. Bowheads are also preyed by killer whales, some die after become trapped and frozen in heavy ice, while others die as result of other natural causes.Where can I find more information about bowhead whales?
Books and the world wide web are excellent places to learn more about marine mammals.
- Leatherwood, Stephen. Reeves, Randall R. Foster, Larry. The Sierra Handbook of Whales and Dolphins. Sierra Club, San Francisco, CA. 1983.
- Leatherwood, Stephen. Reeves, Randall R. Perrin, William F. Evans, William E. Whales, Dolphins, and Porpoises of the Eastern North Pacific and Adjacent Arctic waters; A Guide to their Identification. Dover Publications, Inc., New York, NY. 1988.
- Wynne, Kate. Folkens, Pieter. Guide to Marine Mammals of Alaska. Alaska Sea Grant Program. University of Alaska Fairbanks, Fairbanks, AK. 1992.
World Wide Web
- NMFS Stock Assessment Report
- The Center for Biological Diversity. http://www.biologicaldiversity.org/swcbd/species/bowhead/.
- The Alaska Department of Fish & Game. http://www.adfg.state.ak.us/pubs/notebook/marine/bowhead.php.
There are many more sources to learn about cetaceans. Check with NMML's online library or your local librarian for her or his recommendations.
This portion of the NMML website is intended for a student audience and their educators.
Information within the education website should not be cited in scientific journals or publications.