The bowhead whale (Balaena mysticetus), also called the Greenland right whale, Arctic whale, and polar whale, is a type of baleen whale in the family Balaenidae. It is the only living member of the genus Balaena. This whale is found only in Arctic and subarctic waters and is named for its large, triangular skull, which helps it break through ice.

Bowhead whales have the largest mouths of any animal, making up nearly one-third of their body length. They also have the longest baleen plates among whales, which can measure up to 2.97 to 5.2 meters (9.7 to 17.1 feet). These whales may live longer than any other mammal, possibly reaching over 200 years old.

Bowhead whales were hunted heavily in the past. Their numbers dropped sharply before a 1966 ban was put in place to protect them. According to the IUCN Red List, three of the five bowhead whale populations are classified as "endangered," one as "vulnerable," and one as "lower risk, conservation dependent." However, the global population is considered to be of "least concern."

Taxonomy

Carl Linnaeus named this species in the tenth edition of his Systema Naturae in 1758. At that time, it appeared very similar to related species in the North Atlantic, North Pacific, and Southern Oceans. Because of these similarities, all these species were considered one species, called the "right whale," and given the two-part scientific name Balaena mysticetus.

Today, the bowhead whale is placed in a genus that contains only one species, separate from the right whales. This classification was first proposed by John Edward Gray in 1821. For the next 180 years, scientists debated how to classify the family Balaenidae. They repeatedly grouped the three populations of right whales and the bowhead whale into one, two, three, or four species, sometimes placing them in one genus or two different genera. Eventually, scientists agreed that bowhead whales and right whales are different, but there was no clear agreement on whether they belonged to one or two genera. As recently as 1998, Dale Rice listed only two species—B. glacialis (the right whales) and B. mysticetus (the bowheads)—in his detailed classification system.

Research in the 2000s provided clear evidence that the three living right whale species form a distinct evolutionary family line, separate from the bowhead whale. This confirmed that bowhead whales and right whales belong to two different genera. The right whales were placed in the genus Eubalaena. This relationship is shown in the cladogram below.

Earlier fossil records show no related whales after Morenocetus, a species found in South America and dated to 23 million years ago.

In the 18th century, Emanuel Swedenborg proposed an unknown species of right whale, called the "Swedenborg whale," which was once thought to be a North Atlantic right whale. Later DNA analysis showed that bones claimed to be from Swedenborg whales were actually from bowhead whales.

Description

The bowhead whale is one of the largest baleen whale species. It has a round body, a very curved snout, a large head, and long, dark baleen plates. Compared to its size, the bowhead whale has the largest head of any cetacean, making up nearly 40% of its total body length. Two blowholes are on top of its head and help spray water up to 6.1 meters (20 feet) high. The lower lips cover the baleen plates and look curved and circular when viewed from the side. The whale also has wide, triangular flukes and large, oar-shaped flippers. Its skin is mostly black with white patches on the flukes, tail, eyes, and chin. These patches grow over time, except for the patch near the chin, which appears in newborn calves and grows as the whale grows.

An adult bowhead whale is usually 14 to 18 meters (46 to 59 feet) long and weighs 75 to 100 tonnes (74 to 98 long tons; 83 to 110 short tons). Its fluke is 2 to 6 meters (6.6 to 19.7 feet) long, and it has 230 to 360 baleen plates. The smallest baleen plate measured 2.97 meters (9.7 feet), and the largest measured 4.27 to 5.18 meters (14.0 to 17.0 feet). It is estimated to grow up to 4.3 to 5.2 meters (14 to 17 feet), which is longer than any other whale’s baleen by more than a meter. The whiskers of a bowhead whale that died in 1849 were measured at 5.8 meters (19 feet), but this claim is controversial. The whale’s tongue is 5 meters (16 feet) long and 3 meters (9.8 feet) wide. Female bowhead whales are usually larger than males, reaching lengths of 16 to 18 meters (52 to 59 feet), while males average 14 to 16 meters (46 to 52 feet). Some whales have grown larger than these measurements, with one female reported to be 19.8 meters (65 feet) long in the 1800s. The longest whale measured in photographs was 17.57 meters (57.6 feet).

Studies of DNA from living bowhead whales and baleen used in human tools show that Arctic bowhead whales have lost much of their genetic diversity over the past 500 years. Bowheads used to move between Atlantic and Pacific populations to exchange genes, but whaling and colder weather during the Little Ice Age (16th to 19th centuries) reduced their summer habitats, leading to this loss.

A 2013 study explained the purpose of the bowhead whale’s large palatal organ. This organ, called the corpus cavernosum maxillaris, is a fleshy ridge on the roof of the mouth. It has a structure similar to the corpus cavernosum in the mammalian penis. This organ helps the whale cool itself during physical activity. When the whale opens its mouth, cold seawater flows over the organ, cooling the blood.

In one study, the brains of two male bowhead whales, measuring 12 and 13.3 meters (39 and 44 feet) long, weighed 2.072 and 2.280 kilograms (4.57 and 5.03 pounds) respectively. Their brains had extreme folds and were less folded in the cerebral cortex compared to other cetaceans.

The bowhead whale’s penis can be up to 3 meters (9.8 feet) long, and its testicles usually weigh less than 150 kilograms (330 pounds). However, one whale weighing about 54 tonnes (53 long tons; 60 short tons) had testicles weighing 211 kilograms (465 pounds) and measuring 1.5 meters (4.9 feet) long.

Beluga whales often swim near bowhead whales to observe them and to find open water for breathing, as bowheads can break through thin ice. Bowhead whales can break through ice up to 20 centimeters (7.9 inches) thick, and some sources suggest they may break through ice up to 60 centimeters (24 inches) thick. They also use rocks to remove dead skin from their bodies. Bowhead whales may interact with other whales, such as right whales and sei whales. A hybrid whale, believed to be a mix of a bowhead and a right whale, has also been found.

Behaviour

The bowhead whale is not a social animal and usually travels alone or in small groups of up to six. It can dive underwater for up to an hour, but most dives last between 9 and 18 minutes. The bowhead is not a deep diver, but it can reach depths of up to 150 meters (500 feet). It swims slowly, moving at speeds of 2 to 5 kilometers per hour (0.56 to 1.39 meters per second; 1.2 to 3.1 miles per hour). When fleeing from danger, it can swim faster, reaching speeds of 10 kilometers per hour (2.8 meters per second; 6.2 miles per hour). During feeding, its average speed increases to 1.1 to 2.5 meters per second (4.0 to 9.0 kilometers per hour; 2.5 to 5.6 miles per hour).

The bowhead whale’s head makes up a large part of its body and contains a special feeding structure. It is a filter feeder, meaning it eats by swimming forward with its mouth open. Inside its mouth are hundreds of overlapping baleen plates made of keratin, which hang from the upper jaw. The lower jaw has a large, upturned lip that helps hold the baleen plates in place and prevents them from breaking under water pressure. As the whale swims, water passes through the fine keratin hairs of the baleen plates, trapping small prey near the tongue, which is then swallowed. The whale’s diet includes mostly zooplankton, such as krill, copepods, mysids, amphipods, and other crustaceans. It eats about 1.8 tons (2 short tons) of food each day. Bowheads are usually alone or in groups of two to 10 or more while foraging.

Bowhead whales are very vocal and use low-frequency sounds (less than 1,000 Hz) to communicate during travel, feeding, and socializing. They produce loud calls for communication and navigation, especially during migration. During breeding season, they sing long, complex songs to attract mates. A population near Greenland recorded 184 different songs between 2010 and 2014 from about 300 whales.

Bowhead whales mate in pairs or in groups with several males and one or two females. Breeding occurs from March to August, with conception likely happening in March when singing is most active. They reach sexual maturity at 15 to 25 years and physical maturity at 50 to 60 years. The gestation period lasts 13 to 14 months, and females give birth to a calf every three to four years. There is no evidence that male bowheads lose the ability to reproduce with age, as a 159-year-old male was observed producing sperm. However, some older females may stop reproducing, as seen in females aged 133, 139, and 149 years. The oldest female found with a fetus was estimated to be 121 years old. Lactation lasts about one year, and female bowheads may give birth for up to 100 years.

Newborn calves are born with a thick layer of blubber to stay warm in cold water. Within 30 minutes of birth, calves can swim on their own. A newborn is typically 4 to 4.5 meters (13 to 15 feet) long and weighs about 1,000 kilograms (2,200 pounds). By the end of the first year, it grows to about 8.2 meters (27 feet) in length.

Health

Bowhead whales are the longest-living mammals, with some living over 200 years. In May 2007, scientists studied a bowhead whale that was 15 meters (49 feet) long and caught near Alaska. Inside its body, they found a piece of an old bomb lance, 89 millimeters (3.5 inches) long, made between 1879 and 1885. This means the whale was likely injured by a bomb lance during that time period. Scientists estimated the whale was between 115 and 130 years old when it died. After this discovery, researchers studied the ages of other bowhead whales caught between 1978 and 1996. One male whale was found to be about 211 years old, and others were estimated to be between 135 and 172 years old. These findings showed that bowhead whales live much longer than scientists previously believed. In 2015, scientists from the United States and the United Kingdom mapped the bowhead whale’s complete genome. By comparing this information to other species, they identified two specific gene mutations that may help bowhead whales live longer. These genes are called ERCC1 and PCNA. ERCC1 helps repair damaged DNA and reduces the risk of cancer. PCNA also plays a role in DNA repair. These genetic changes allow bowhead whales to repair their DNA more effectively, which helps them resist cancer. Scientists also found that bowhead whales may have lower metabolic rates than other mammals. A gene called UCP1, which is involved in body temperature regulation, may explain these differences in metabolism.

Ecology

The bowhead whale is the only baleen whale that lives its entire life in Arctic and subarctic waters. The Alaskan population spends the winter in the southwestern Bering Sea. In the spring, these whales move northward through openings in the ice into the Chukchi and Beaufort seas. The area where bowhead whales live depends on changes in climate and the formation or melting of ice.

Historically, bowhead whales may have lived in a larger area that included parts of Labrador, Newfoundland (Strait of Belle Isle), and the northern Gulf of St. Lawrence until at least the 16th and 17th centuries. It is not clear if this was because the climate was colder back then. Fossils of Balaena spp. from the Pleistocene era have been found in Italy and North Carolina, suggesting these whales may have lived farther south than they do today.

Worldwide, there are between 10,000 and 25,000 bowhead whales, with a maximum population of 43,000. Scientists recognize five main groups of bowhead whales: 1) the Western Arctic group in the Bering, Chukchi, and Beaufort Seas, 2) the Hudson Bay and Foxe Basin group, 3) the Baffin Bay and Davis Strait group, 4) the Sea of Okhotsk group, and 5) the Svalbard-Barents Sea group. Recent studies suggest the Hudson Bay and Foxe Basin group and the Baffin Bay and Davis Strait group should be considered one group because of genetic similarities and whale movement patterns.

The Western Arctic population, also called the Bering-Chukchi-Beaufort population, has grown since commercial hunting stopped in the early 1900s. A 2019 study estimated this population at 12,505, which was lower than the 2011 estimate of 16,820. However, researchers believe the population did not decline significantly between 2011 and 2019 due to unusual migration and observation conditions in 2019. From 1978 to 2011, this population grew by 3.7% each year. These data suggest the Western Arctic bowhead population may be close to its size before commercial whaling. Climate change is affecting the migration patterns of this group.

Alaskan Native communities continue to hunt small numbers of bowhead whales for subsistence. The Alaska Eskimo Whaling Commission works with the National Oceanic and Atmospheric Administration to manage these hunts. Villages that participate in subsistence hunting include Barrow, Point Hope, Point Lay, Wainwright, Nuiqsut, Kaktovik, Gambell, Savoonga, Kivalina, Wales, and Little Diomede. The annual subsistence harvest of the Western Arctic stock has ranged from 14 to 72 whales, which is about 0.1–0.5% of the population.

In March 2008, Canada’s Department of Fisheries and Oceans reported that previous estimates for the eastern Arctic were too low. A new estimate of 14,400 bowhead whales (range: 4,800–43,000) was given, matching prewhaling numbers. This suggests the population has recovered fully. However, if climate change reduces sea ice, these whales could face risks from increased shipping traffic.

Information about other populations is less complete. In 2006, about 1,200 bowhead whales were observed near West Greenland, while the Svalbard population may number only in the tens. However, recent years have shown an increase in these numbers.

The Hudson Bay–Foxe Basin population is separate from the Baffin Bay–Davis Strait group. Historical records suggest about 500 to 600 whales summered in the northwestern part of Hudson Bay in the 1860s. Today, the number of whales in Hudson Bay is likely smaller than the total population, but reports from Indigenous people indicate the population is growing. Bowhead whales use larger areas of Hudson Bay for summering and smaller areas for wintering. Some whales winter in Hudson Strait, especially near Igloolik Island and northeastern Hudson Bay. The presence of orcas (killer whales) affects the distribution of bowhead whales in these regions. Climate change may increase orca attacks on bowhead whales because reduced sea ice limits the areas where bowheads can hide.

Whaling in the 19th century occurred in areas from Marble Island to Roes Welcome Sound, Lyon Inlet, and Fisher Strait. Bowhead whales still migrate through these regions today. In Hudson Bay, bowhead whales are mostly found in the northwestern part, including Wager Bay, Repulse Bay, Southampton Island (a major summering area), Frozen Strait, northern Foxe Basin, and north of Igloolik in summer. Satellite tracking shows some whales stay north of Whale Cove and areas south of Coats and Mansel Islands. Summering groups in the northern Foxe Basin include cow–calf pairs and young whales up to 13.5 meters (44 feet) long, while older males and non-calving females may use the northwestern part of Hudson Bay. Fewer whales migrate to the west coast of Hudson Bay and Mansel and Ottawa Islands. Bowhead whales in Hudson Bay typically do not travel to southern areas, but some may reach Sanikiluaq and the mouth of the Churchill River.

In Foxe Basin, bowhead whales gather in a specific area north of Igloolik Island, extending to Fury and Hecla Strait, Kapuiviit, Gifford Fiord, the Gulf of Boothia, and Prince Regent Inlet. In spring, some whales move northward along the western side of Foxe Basin to the eastern side.

Little is known about the Sea of Okhotsk population. These whales are often seen near the Shantar Islands, close to shore, such as at Ongachan Bay. Whale-w

Whaling

The bowhead whale has been hunted for blubber, meat, oil, bones, and baleen. Like the right whale, it swims slowly and floats after death, making it easy to hunt. Before commercial whaling, scientists estimated there were about 50,000 bowhead whales. Evidence from ancient Eskimo sites shows people hunted and ate bowhead whales as far back as 4000 BC. Inuit people near the Pacific Ocean created special tools to hunt these whales, which provided food and fuel for their communities.

Commercial whaling of bowhead whales began in the 16th century when the Basques hunted them as they migrated south through the Strait of Belle Isle in the fall and early winter. In 1611, the first whaling expedition traveled to Spitsbergen. A whaling settlement called Smeerenburg was built on Spitsbergen in 1619. By the middle of the 17th century, the whale population in that area had nearly disappeared, forcing whalers to travel farther north into the "West Ice"—the pack ice near Greenland’s east coast. By 1719, whalers reached the Davis Strait, and by the early 1800s, they were hunting in Baffin Bay.

In the North Pacific, the first bowhead whales were hunted off the eastern coast of Kamchatka by the Danish ship Neptun, led by Captain Thomas Sodring, in 1845. In 1847, bowhead whales were first caught in the Sea of Okhotsk. The following year, Captain Thomas Welcome Roys of the ship Superior from Sag Harbor caught bowhead whales in the Bering Strait region. By 1849, 50 ships were hunting bowhead whales in each area. In the Bering Strait, 500 whales were killed in 1849, and this number increased to over 2,000 in 1850. By 1852, 220 ships were hunting in the Bering Strait region, killing more than 2,600 whales. Between 1854 and 1857, whalers moved to the Sea of Okhotsk, where 100–160 ships hunted annually. From 1858 to 1860, whalers returned to the Bering Strait region, where most ships hunted during the summer until the early 1900s. Between 1848 and 1914, an estimated 18,600 bowhead whales were killed in the Bering Strait region, with 60% of those killed in the first 20 years. Between 1847 and 1867, about 18,000 bowhead whales were killed in the Sea of Okhotsk, with 80% of those killed in the first 10 years.

Bowhead whales were first hunted near the pack ice in the northeastern Sea of Okhotsk, then in Tausk Bay and the Northeast Gulf (Shelikhov Gulf). Later, whalers expanded their hunting to the west, catching whales near Iony Island and the Shantar Islands. In the Western Arctic, whalers mainly hunted bowhead whales in the Anadyr Gulf, the Bering Strait, and around St. Lawrence Island. They later hunted in the western Beaufort Sea (starting in 1854) and the Mackenzie River delta (starting in 1889).

Commercial whaling, the main reason for the decline in bowhead whale numbers, has ended. Today, bowhead whales are only hunted by Native peoples of North America for subsistence.

In 2024, Inuit hunters in Aklavik, Northwest Territories, were allowed to hunt and kill one bowhead whale. The whale meat was shared with Inuvialuit and Gwich'in communities in the region, as it is an important part of Inuit cuisine.

Conservation

The bowhead whale is listed in Appendix I by CITES. Even though the worldwide population is considered safe and given a "least concern" status, some groups are listed as "endangered" by the National Marine Fisheries Service under the United States' Endangered Species Act. The IUCN Red List reports the following statuses for different bowhead whale groups:

• Svalbard population – critically endangered
• Sea of Okhotsk group – endangered
• Baffin Bay – Davis Strait group – endangered
• Hudson Bay – Foxe Basin group – vulnerable (estimated to have 1,026 individuals in 2005 by DFO)
• Bering – Chukchi – Beaufort group – lower risk – conservation dependent

The Alaska Department of Fish and Game and the U.S. government list the bowhead whale as federally endangered.

The bowhead whale is also listed in Appendix I of the Convention on the Conservation of Migratory Species of Wild Animals (CMS). This listing means the species is at risk of extinction across all or part of its range. CMS members work to strictly protect these animals, preserve their habitats, remove barriers to migration, and manage other threats that could harm them.

Cited sources

Burns, J. J., Montague, J. J., and Cowles, C. J., editors. (1993). The Bowhead Whale. Special Publication Number 2. Lawrence, Kansas: The Society for Marine Mammalogy. ISBN 0-935868-62-3.