Updated: July 2020
The bowhead whale is a large baleen whale. With a body mass of up to 100 tonnes and a length of up to 20 m, the bowhead whale is one of the largest animals on the planet. Females are slightly larger than males. The bowhead whale has no dorsal fin unlike the majority of other baleen whales. The disproportionally large head constitutes more than one-third of the entire length of the animal. The name bowhead is associated with the whale’s high, arched lower jaw that looks like an archer’s bow.
Bowhead whales are predominately black but with much of their chin and lower jaw being white. A row of pigmented spots is also located on each side of the lower jaw. A light grey or whitish band around the peduncle in front of the fluke is seen in some (older) whales. The bowhead whale is the longest-living mammal on the planet and can reach an impressive age of around 200 years.
The Eastern Canada-West Greenland stock is around 6,400 animals while the Spitzbergen stock is around 100 animals.
Bowhead whales can be found in the circumpolar Arctic and sub-Arctic waters. Two stocks inhabit the North Atlantic – one in Eastern Canada-West Greenland, and one in the Greenland Sea-Svalbard area.
Bowhead whales have historically been hunted by Inuit and there has also previously been a large commercial hunt. Currently small numbers are taken by Inuit in Canada and Greenland.
Populations were reduced by historical whaling but the Eastern Canada-West Greenland stock is increasing and new evidence shows possible increases in the Spitzbergen stock as well. Hunting is managed by DFO in Canada. Greenland obtains quotas from the IWC and gives additional regulations.
In the most recent assessment (2018) the East Greenland-Svalbard-Barents Sea subpopulation is listed as ‘Endangered’ on the IUCN Red List. On a global scale, bowhead whales are listed as ‘Least Concern’ on the IUCN Red List (2018).
Scientific name: Balaenoptera physalus (Linnaeus 1758)
Icelandic: Grænland hvalur
English: Bowhead whale, Greenland right whale or Arctic whale
Bowheads average length is approximately 18 m long (although they can reach a length of 20 m). They have a body mass of 70-100 tonnes. Females are larger than males
Bowhead whales live up to ~200 years (George et al. 1999).
Bowhead whales are filter feeders. They feed by swimming slowly forward with their mouth wide open. Their diet consists of zooplankton, mainly copepods
They have one calf every 3-4 years from a body length of 13-13.5 m at around 25 years of age.
The bowhead is an Arctic resident, living its whole life in Arctic or sub-Arctic waters. It is migratory, with a seasonal appearance in certain areas and this migration is influenced by the distribution of sea ice.
The bowhead whale belongs to the family Balaenidae and genus Balaena.
The bowhead whale is thick-bodied compared to other baleen whales. The head constitutes one third of the body length and the baleen plates are correspondingly longer. The skin is smooth, the back broad and there is no dorsal fin or dorsal hump. The paired blowholes are located on a distinct elevation called the crown. The eyes are located quite low on the sides of the head. Flippers are short and broad.
Colouration is predominately black with the chin and lower jaw being white. A row of pigmented spots is located on each side of the lower jaw. In some (older) whales a light grey or whitish band around the peduncle in front of the fluke is seen. The amount of white on the fluke and tail increases with age. Older individuals can be whiter on the head and can be heavily scarred (Reeves & Leatherwood 1985). The blubber layer of the bowhead whale is thick, ranging from 5.5 cm on the chin to 28 cm on the trunk (Haldiman & Tarpley 1993).
Adult bowhead whales measure 12–18 m in length with some individuals reaching lengths of ~20 m (Haldiman & Tarpley 1993). By calculating the volume and weight of water displaced by a model made to scale a bowhead whale ‘of typical proportions’, it was estimated to have a mass of 75 tons (Reeves & Leatherwood 1985). Females are typically larger than males. The flippers are short and broad with lengths ranging from 97–304 cm. Fluke width averages 33% of body length (Haldiman & Tarpley 1993).
Bowhead whales are relatively slow swimmers. Their migratory speed has been reported at approximately 1.1–2.5 m/s, which is in the same range as the mean speed for baleen whales when foraging at the surface (Simon et al. 2009, Heide-Jørgensen et al. 2006). Tracking of whales with satellite transmitters in West Greenland in winter has shown whales to travel fast through dense pack ice. Three whales (one male and two females) were shown to travel 1,730–5,888 kilometres during one month. The authors hypothesised that bowhead whales have the potential to cross stock boundaries that were perhaps not anticipated when the boundaries were established (Heide-Jørgensen et al. 2006).
Watch drone video of bowhead whales
The large head of the bowhead whale, which comprises approximately one-third of its total body length, functions as an enormous feeding device. The impressive mouth gap is more than 4 m2. The mouth forms a gigantic filtering apparatus with baleen plates up to 4 m long (Simon et al. 2009).
When foraging, bowhead whales move at very slow speeds, less than 1 m/s. Each foraging dive can amount to ~2000 tons of filtered water and prey. Bowheads are not deep divers. Simon et al. (2006) showed a maximum foraging dive depth of 127 m and a mean dive time of 11–20 min per dive. The bowhead whale diet consists mainly of zooplankton, especially Calanus copepods and amphipods as well as other small crustaceans.
Sounds and Communication
Bowhead whales are highly vocal. They use sounds for communication, socializing, foraging, navigation, and mate selection. Five species of baleen whales are known to produce songs: the bowhead whale, blue whale (Balaenoptera musculus), humpback whale (Megaptera novaeangliae), fin whale (Balaenoptera physalus) and minke whale (Balaenoptera acutorostrata). Bowhead whale singing is most intense in the breeding season but they have also been reported singing in other seasons (Reese et al. 2001, Würsig & Clark 1993).
Stafford et al. (2012) found bowhead whales in Fram Strait (between Greenland and Svalbard) to call or sing continuously from November 2008 through April 2009. More than 60 unique songs were recorded. Also, Johnson et al. (2014) found great variability in songs for bowhead whales from the Bering-Chukchi-Beaufort stock and that songs were shared among individuals.
Social and sexual behaviour
Bowhead whales are often segregated by size, sex, and reproductive state during migration and in their summering grounds. Population segregation may be related to predatory pressures, diving abilities and habitat partitioning (Finley 2001). There are different reports regarding bowhead whale social organisation relating to populations, sex of the animal, age, and whether females are traveling with a calf. Bowheads have been observed in great numbers, for example in areas with plenty of food or when traveling between sites. However, whether or not they are gregarious animals as such is still an open question. Large aggregations of up to 20–60 animals have been observed along the east coast of Baffin Island and in the Beaufort Sea. In the Svalbard-Barents Sea stock only individuals or pairs have been observed. During migration, bowheads often travel alone, in pairs, or in small groups (Reeves & Leatherwood 1985).
Sexual interaction between bowhead whales has been observed during the spring migration in the western Arctic but has also been observed in the fall for animals of the Bering Sea stock. For the Eastern Canada–Western Greenland stock, sexual behaviour has been reported in the fall at Isabella Bay, North East Canada. Sexual activity can take place between pairs of whales but most often occurs in larger ’mating’ groups (Würsig & Clark 1993).
The bowhead whale is one of the stockiest whales of appearance. Compared to the fast fin whale, for example, the bowhead whale is a relatively slow swimmer. When swimming, only the whale’s head and the rounded back are above the water surface.
The bowhead whale has many structural similarities to right whales. Two obvious characteristics distinguish them from each other; the bowhead whale’s higher arch of the upper jaw and the absence of bonnet callosities (bumps of hardened skin on the top of the rostrum) (Haldiman & Tarpley 1993).
The bowhead whale’s two blowholes send a V-shaped blow several meters in the air when the bowhead whale spouts.
DID YOU KNOW?
Bowhead Whales Can Cool Themselves Down Using an Erectile Organ on the Roof of their Mouth
Bowhead whales have a large palatal retial organ (roof of the mouth). Here they have a bulbous ridge of highly vascularised tissue (called the corpus cavernosum maxillaris) that extends down the centre line and forms two large lobes on their palate. Histological examination has revealed a large numbers of blood vessels and vascular as well as extravascular spaces that make it resemble a blood‐filled, erectile sponge, similar to that of the corpus cavernosum of the mammalian reproductive organ.
It is hypothesized that this organ provides a cooling mechanism for the whale. Protected from the cold Arctic waters it inhabits by 40 cm (16 in) or more of fat, the bowhead needs an efficient way to cool down under all this blubber when it has to be active. During physical exertion, the whale must cool itself to prevent hyperthermia and ultimately brain damage. It is believed that this organ becomes engorged with blood and that the whale can then open its mouth to allow cold seawater to flow over the organ and thus cool the blood down.
You can find the full article describing this unique cooling mechanism here.
The bowhead whale is probably the longest-lived mammal on earth. It can reach an impressive age of more than 200 years. The oldest estimated individual was 211 years old and was from Alaska. It was estimated using aspartic acid racemisation in the nucleus of the eye. Recoveries of traditional whale-hunting tools from some hunted whales also indicate life-spans in excess of 100 years of age (George et al. 1999).
Conception in bowhead whales is believed to occur around a mean date of 24th March (Reese et al. 2001, Heide-Jørgensen et al. 2007). Mean length of gestation in bowheads from the Bering-Chukchi-Beaufort Sea stock was estimated at 13.9 months, with parturition likely to occur in May–June. Disko Bay in West Greenland is used as a spring feeding ground and probably also a mating ground for bowhead whales from Eastern Canada and West Greenland. Near-term pregnant females have been observed in this area but females are rarely accompanied by calves. Parturition in this population thus likely occurs after the whales have visited Disko Bay in April–May, probably around the same time as the Bering-Chukchi-Beaufort Sea stock (Heide-Jørgensen et al. 2012a).
The estimated body length at sexual maturity for female bowhead whales is around 13 m (George et al. 2004, Heide-Jørgensen et al. 2012a) at an age of ~25 years (Rosa et al. 2013). Male bowhead whales reach sexual maturity at body lengths of >12.7m (O’Hara et al. 2002) and probably at around the same age as the females (Rosa et al. 2013).
Near-term foetuses have been measured to be 3.9–4.3 m long and lengths of small calves 3.63–4.29 m have been observed in May (see Koski et al. 1993). Lactation probably lasts a year (George et al. 1999). Average calving rate is assumed to be 3–4 years and is unlikely to be less than 3 years (Koski et al. 1993).
The only known natural predator of the bowhead whale is the killer whale (Orcinus orca).
Distribution and Habitat
Bowhead whales are endemic to Arctic and subarctic waters. The bowhead whale is the only baleen whale found year round in the Arctic. The overall distribution of bowhead whales spans approximately latitudes 54–75°N in the North Pacific basin and 60–85°N in the North Atlantic basin (Moore & Reeves, 1993). Four management stocks of bowhead whales occupy the Northern Pacific Ocean, the North West Atlantic Ocean and the North East Atlantic Ocean.
Distribution in the North Atlantic
Bowhead whale distribution in the Northwest Atlantic includes the western Arctic Canada from the Canadian high Arctic Archipelago to Hudson Bay in the South, Baffin Bay, Davis Strait, the West coast of Greenland (with a southernmost limit at approximately 66°N (Moore & Reeves, 1993)) and northern Greenland.
The population in the Northeast Atlantic is distributed from the Greenland Sea between East Greenland to the Barents and Kara seas and into the Russian Arctic.
Bowhead whales live in close association with sea ice. They are migratory of nature, generally migrating to the high Arctic in summer and moving southward in winter with the advancing ice edge. More on migration is found in the section North Atlantic stocks: Bowhead whale migration in the North Atlantic.
For management, at least four geographic stocks of bowhead whales are recognised. The stocks are geographically separated by landmasses or extensive sea ice. The stocks are:
- The Eastern Canada-West Greenland (EC–WG) stock (Frasier et al. 2015)
- The Svalbard-Barents Sea stock (or the Spitsbergen stock)
- The Bering-Chukchi-Beaufort Sea stock
- The Okhotsk Sea stock
The International Whaling Commission (IWC) operates with the EC-WG population as being two distinct stocks: the Hudson Bay-Foxe Basin stock and the Baffin Bay-Davis Strait stock. The reason behind the stock delineation was the separation of bowhead whale summering areas in Baffin Bay and Foxe Basin, and the assumption that baleen whales make seasonal north-south movements rather than east-west movements. Exchange between the bowhead whale summering populations was therefore considered unlikely.
However, neither historic nor scientific evidence has been presented confirming the separation of these two stocks. On the contrary, scientific studies based on photographic evidence and satellite tracking have linked bowhead whales between West Greenland and the Hudson Strait (Heide-Jørgensen et al. 2006). Furthermore, genetic studies support a one-stock hypothesis for the EC-WG bowhead whale population. It has also been found that whales from the EC-WG population are genetically distinct from the more westerly Bering-Chukchi-Beaufort population (DFO 2015).
For management purposes, particularly in regard to establishing quotas for subsistence hunting, it is essential to know the stock structure of populations. The recognition of one stock of bowhead whales in Foxe Basin-Hudson Bay/Baffin Bay-Davis Strait has led to a shared quota for the stock instead of different quotas for each of the two areas (DFO 2009, 2015).
Bowhead whale migration in the North Atlantic
Migratory patterns of bowhead whales have been documented from aerial surveys, shore- and ship-based observations, telemetry studies, and from subsistence whaling activities. Bowhead whales from the EC-WG stock spend the winter in Hudson Strait, northern Hudson Bay, or along the pack-ice edge extending to coastal West Greenland. Bowhead whales may also be found in winter in the North Water and in polynyas along the east coast of Baffin Island. In spring, the whales are found along the West Greenland coast (primarily Disko Bay), in Hudson Strait, Cumberland Sound, and the entrance to Lancaster Sound. In spring, the whales cross Baffin Bay from Disko Bay to Lancaster Sound. The whales stay within the high Canadian Arctic or along the east coast of Baffin Island in summer and early fall and winter in Hudson Strait or at the West Greenland coast (Heide-Jørgensen et al. 2006).
Recently a study showed overlap of the EC-WG stock and the Bering-Chukchi-Beaufort stock when two whales spent time in the same area in the Northwest Passage in the high Canadian Arctic (Heide-Jørgensen et al. 2012b). Sea ice in the Northwest Passage is thus perhaps no longer a physical barrier separating bowhead whales from the Pacific and Atlantic Oceans as previously assumed.
Svalbard-Barents Sea stock
The Svalbard-Barents Sea stock, also called the Spitsbergen stock, is confined to the Northeast Atlantic from the Greenland Sea between East Greenland to the Barents and Kara Seas and into the Russian Arctic (Norwegian Polar Institute 2016). Little is known about the migratory behaviour of this small stock. A survey conducted in April 2006 found whales in Fram Strait between East Greenland and Svalbard, which is a wintering site for this population (Wiig et al. 2007). There have also been bowhead sightings from Spitsbergen fjords during summer. Historical records from whaling operations show that whales stay north and northwest of Spitsbergen in spring, and around Jan Mayen in the same seasons. Whales were also found in the Greenland Sea in May–June. The seasonal pattern for this population is “up-side down” compared to other populations that travel north in summer and south in winter (Moore & Reeves 1993).
In April 2010, a satellite transmitter was deployed on a female bowhead whale from the Svalbard-Barents Sea stock for the first time. The whale was tagged in Fram Strait where she initially remained before beginning a southwest migration and staying between ~70 ̊–73 ̊N until the tag stopped continuous transmissions in late July. Data showed that the whale spent most of its time in waters close to the ice edge, over areas where the bottom slope was relatively steep. Data was also transmitted in winter, where positions from late November until late December 2010 showed that the whale was back in the North at about 80 ̊ N.
The authors suggest that this stock overwinters at high-latitude locations and that the migratory pattern of this whale during summer is consistent with the patterns that early whalers described for bowhead whales in this region in the 16th and 17th centuries (Lydersen et al. 2012). A recent study proposes the Northeast Water Polynya (NEW) in the Greenland Sea to be one of the most important summering grounds for this stock (Boertmann et al. 2015).
Current Abundance and Trends
Abundance estimates of the North Atlantic bowhead whales have been generated from aerial surveys using line transects, surveys from vessels, and from mark-recapture studies. Surveys conducted in Canada and Greenland have estimated the abundance of the EC-WG stock, while those carried out by Greenland and Norway have been used for the Svalbard-Barents Sea stock.
In 1981, aerial surveys of the winter range of the EC-WG stock provided an estimate of a total population abundance of 1,349 (95% CI: 402–4,529) (Koski et al. 2006). Surveys carried out in Eastern Canadian and West Greenland waters after that time suggested that there were hundreds of bowhead whales present, although the range of coverage was limited and important seasonal aggregations had often been missed (see references in Frasier et al. 2015).
In the early 2000s (2002-2004), aerial surveys of the EC-WG population in Canadian waters were conducted by the Department of Fisheries and Oceans Canada (DFO). Several statistical analyses suggested abundance estimates in the range from 6,344 (95% CI: 3,119–12,906) to 14,400 (95%CI: 4,811–43,105) individuals (see references in Frasier et al. 2015). In August 2013, DFO conducted the High Arctic Cetacean Survey (HACS) to update previous abundance estimates for the EC-WG bowhead whale population. The survey achieved almost complete coverage of important summer aggregation areas. The fully corrected abundance estimate was 6,446 (CV 26%) (Doniol-Valcroze 2015). The estimates indicate that the EC-WG population has increased significantly since bowhead whales were first protected from commercial whaling in the 1930s.
Until recently, the protected Svalbard-Barents Sea stock was believed to number in the tens of animals (Lydersen et al. 2012). However, a an aerial survey conducted in summer 2009 estimated 102 (95 % CI: 32-329) bowheads in the Northeast Water Polynya (NEW). This result showed the largest abundance of bowhead whales reported from the Greenland Sea since the whaling period and saw the authors conclude that the NEW could be one of the most important summering grounds for the Svalbard-Barents Sea bowhead stock and that this stock could be recovering (Boertmann et al. 2015). The whales forage on calanoid copepods from the productive deep basins along the coast of Svalbard east of the NEW (Boertmann et al. 2015).
Total abundance in the Northern Atlantic in 2016: ~8000 bowheads
In 2016, total abundance of the North Atlantic bowhead whale stocks (the EC-WG stock and the Svalbard-Barents Sea stock) was estimated as being nearly 8,000 animals.
Based on Bayesian analyses of genetic mark-recapture data, Frasier et al. (2015) estimated a total abundance estimate of 7,660 (95% CI: 4,500–11,100) for the EC-WG bowhead whale population. The results are consistent with a population increase throughout the 19-year study period.
A case study: Increasing abundance of bowhead whales in West Greenland
A study in April 2006, showed a significant increase in the winter population abundance of bowhead whales on the former whaling grounds in West Greenland. The result was surprising, as the change in abundance couldn’t be explained by recent or rapid growth in population size. One hypothesis was that the population, which showed a higher abundance of mature females, had recently attained a certain threshold size elsewhere. The authors also noted that a severe reduction in sea ice facilitated access to coastal areas and that these two factors in combination could explain the increase in the occurrence of whales in the area.
Consequently, a survey in West Greenland documented the largest number of bowhead whales recorded in the area for the past 100 years. This was a first clear indication that the population was increasing (Heide-Jørgensen et al. 2007). A recent study from 2015, however, indicates that the observed increase in abundance (between 1998 and 2006) has levelled off (Rekdal et al. 2015).
Bowhead whales have been protected since 1931, apart from limited and low levels of subsistence whaling. Only the EC-WG stocks and the Bering-Chukchi-Beaufort stock are subject to subsistence whaling, while the two other recognised management stocks are fully protected.
Three out of the four bowhead whale stocks seem to be increasing in abundance (see Table below). For the Okhotsk Sea, data is insufficient for estimating abundance but according to IWC, the population appears small and is subject to both anthropogenic and natural pressures (IWC 2016a). IWC recommends that an abundance estimate be obtained for this population.
Abundance estimates, trends and current status from the International Union for Conservation of Nature (IUCN) Red List of Threatened Species (IUCN 2016) for the four bowhead whale stocks are also summarised in the table below. The IUCN operates with a separate status for each of the four management stocks.
Conservation status according to other international organisations
The Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) lists the bowhead whale as one mega-population, grouping the four recognised populations in Appendix I – ‘threatened with extinction’. CITES does not distinguish between the status of the different stocks. As is the case for the fin whale (see also fin whale – Stock status), pooling of different populations together under a single listing can be misleading as the stocks are by definition reproductively isolated and may have very different conservation histories. This is particularly misleading when the populations pooled together are very different in size, as is the case for the EC-WG and Bering-Chukchi-Beaufort stocks, which are much larger than the Svalbard-Barents Sea and Okhotsk Sea stocks (NAMMCO 2016).
Abundance estimates, trends in abundance and stock status of bowhead whale stocks worldwide.
|Bowhead Whale Stock||Abundance estimate||95% Confidence Intervals||Trend||IUCN* Status||Method||Reference|
|Eastern Canada – West Greenland||7,660||4,500 – 11,100**||Increasing||Least concern||Genetic capture-mark-recapture (2008-12)||Frasier et al., 2015|
|Spitzbergen (Svalbard – Barents Sea)||At least 100||N/A||Unknown||Endangered||Aerial survey (2009), ship survey (2006)||Boertmann et al., 2015; Wiig et al., 2007|
|Bering – Chukchi – Beaufort Seas||12,361||7,900 – 19,700||Increasing||Least concern||Photo-identification||Koski et al., 2010|
|Okhotsk Sea||No available estimate, but presumably small (a few hundred)||N/A||Unknown||Endangered||None||IWC, 2016|
*From IUCN (International Union for Conservation of Nature), the IUCN Red List of Threatened Species.
**A fully corrected line transect estimate for 2013 for all the major summering areas of the bowhead population in East Canada, excluding Foxe Basin, Repulse Bay and Lancaster Sound gave an abundance estimate of 6,446 (CV: 26%) (Doniol-Valcroze et al. 2015). Number of whales visiting West Greenland was estimated to 1,274 (CV=0.12) for 2012 via mark-recapture (IWC 2015).
In the North Atlantic, the bowhead whale is managed by two international management organisations: the North Atlantic Marine Mammal Commission (NAMMCO) and the IWC, for those countries that are members. Canadian takes are managed domestically.
Commercial bowhead whaling was prohibited in 1931. Canada and Greenland resumed hunting bowheads from the EC-WG stock in 1996 and 2008 in the form of aboriginal subsistence whaling.
Management measures in NAMMCO member countries
The last updated list of laws and regulations in NAMMCO countries regarding the hunting of marine mammals (including protection and hunting methods) can be found here.
The Ministry of Fisheries and Hunting regulates and administers hunting in Greenland (Government of Greenland 2016). Some of the regulations apply to hunting in general (Home Rule Act no. 12, 29-10-1999, and later amendments in 2001, 2003 and 2008), animal welfare (Home Rule Act no. 25, 18-12-2003), nature protection (Home Rule Act no. 29, 18-12-2003), and hunting permits (Executive order nr. 20, 27-12-2003), while others specifically address the hunting of large whales. In addition to the rules of the Government of Greenland, there may also be additional rules set by the municipalities.
There is no private ownership of land, sea or living resources in Greenland. Hunting grounds and game animals are open to hunt and use by Greenlandic citizens, subject to hunting licenses. However, only persons with a full-time occupational hunting license are allowed to hunt large whales and there are a number of important conditions and limitations, including those related to catch limits, methods of hunting, training and reporting.
Locally, a team of wildlife officers/wardens control hunting and fishing activities, making sure that conservation measures of protected areas and species are observed and passing information on to the local community. The wildlife officers work in close cooperation with the municipalities, the police, and the Government of Greenland.
The IWC determines the catch quotas for bowhead whales taken in Greenland. The quota year for bowheads is from April 1st to December 31st.
Bowhead whales are fully protected in Norway. Whaling is under the authority of the Ministry of Trade, Industry and Fisheries (Government of Norway 2016). Currently, the common minke whale (Balaenoptera acutorostrata) is the only whale species that can be legally hunted in Norway.
Hunting and utilisation
Subsistence hunting for bowhead whales by Inuit in Canada, Greenland and Alaska is important providing traditional food and livelihoods, and for sustaining cultural traditions and values. Although the bowhead whale populations have been protected from commercial hunts since 1931, the Inuit in Canada, Greenland and Alaska can catch a limited number of whales under management regimes for aboriginal subsistence whaling. The small number of whales hunted by indigenous people in Canada is managed domestically. Quotas for catches in Greenland and Alaska are set by the IWC (IWC 2016b). Inuit in Canada resumed bowhead whale hunting in 1996, and 24 bowhead whales were taken in the period 1996-2014 (DFO 2015). Inuit in Greenland resumed bowhead whale hunting in 2008, and 8 bowhead whales have been taken in the period 2008-2019.
The bowhead whale was almost hunted to extinction by European and American commercial whalers over a nearly 400-year period between the 1500s and the 1900s. All stocks of bowhead whales were exploited. Currently, of the two North Atlantic stocks, only the EC-WG stock is exploited while the Svalbard-Barents Sea stock is fully protected throughout its range.
In Eastern Canada, two Inuit communities—the Nunavut Settlement Area and the Nunavik Marine Region (northern Quebec)—resumed subsistence hunts for bowhead whales in 1996 and in 2008, respectively. The hunts are co-managed by the Nunavut Wildlife Management Board, the Nunavik Marine Region Wildlife Board, and Fisheries and Oceans Canada. Hunting is licensed by the DFO (DFO 2015).
It has been estimated that the EC-WG bowhead whale population can support a total human-induced mortality of 52 whales annually, resulting from all sources of anthropogenic mortality including hunt, struck and loss, net entanglements and ship collisions (Doniol-Valcroze 2015). The current annual level of total allowable hunt is five bowhead whales in Nunavut and two in Nunavik. It is prohibited to catch calves less than 7.6 m in length and females accompanied by calves (DFO 2015). The table to the right lists the bowhead catches in Eastern Canada from 1996 to 2014, a total of 24 catches.
The West Greenland hunt for bowhead whales from the EC-WG stock resumed in 2008 under conditions established by the IWC (DFO 2015). In 2014, the IWC re-approved two strikes per year for West Greenland with the requirement for an annual review by the IWC Scientific Committee. The catch history of bowheads in West Greenland since 2008 is listed in the table below. The Government of Greenland allows unused catches to be transferred to the following year.
Subsistence hunts for bowhead whales in Nunavut and Nunavik
|1996||Repulse Bay, NWT1||M||14.91|
|2000||Coral Harbour, NU||M||11.65|
|2005||Repulse Bay, NU||F||16.40|
|2008||Hall Beach, NU||M||13.43|
|2009||Rankin Inlet, NU||F||16.15|
|Cape Dorset, NU||M||15.77|
|2010||Pond Inlet, NU||M||12.80|
|Repulse Bay, NU||F||14.32|
|2011||Coral Harbour, NU||F||16.38|
|2012||Arctic Bay, NU||M||8.99|
|Repulse Bay, NU||M||8.10|
|Repulse Bay, NU||F||15.72|
|Gjoa Haven, NU||M||9.75|
|2014||Clyde River, NU||F||16.00|
1Prior to 1999 when Nunavut separated from the Northwest Territories.
Catches in NAMMCO member countries since 1992
|Country||Species (common name)||Species (scientific name)||Year or Season||Area or Stock||Catch Total||Quota (if applicable)|
|Greenland||Bowhead whale||Balaena mysticetus||2021||Baffin Bay-Davis Strait||0||2|
|Greenland||Bowhead whale||Balaena mysticetus||2020||Baffin Bay-Davis Strait||0||2|
|Greenland||Bowhead whale||Balaena mysticetus||2019||West||0||0|
|Greenland||Bowhead whale||Balaena mysticetus||2018||West||0||4|
|Greenland||Bowhead whale||Balaena mysticetus||2017||West||0||4|
|Greenland||Bowhead whale||Balaena mysticetus||2016||West||0||4|
|Greenland||Bowhead whale||Balaena mysticetus||2015||West||1||4|
|Greenland||Bowhead whale||Balaena mysticetus||2014||West||0||4|
|Greenland||Bowhead whale||Balaena mysticetus||2013||West||0||2|
|Greenland||Bowhead whale||Balaena mysticetus||2012||West||0||3|
|Greenland||Bowhead whale||Balaena mysticetus||2011||West||1||2|
|Greenland||Bowhead whale||Balaena mysticetus||2010||West||3||3|
|Greenland||Bowhead whale||Balaena mysticetus||2009||West||3||4|
|Greenland||Bowhead whale||Balaena mysticetus||2008||West||0||2|
|Greenland||Bowhead whale||Balaena mysticetus||2007||West||0||2?|
|Greenland||Bowhead whale||Balaena mysticetus||1992-2006||West||*No reported catches|
This database of reported catches is searchable, meaning you can filter the information, e.g. by country, species or area. It is also possible to sort it by the different columns, in ascending or descending order, by clicking the column you want to sort by and the associated arrows for the order. By default, 30 entries are shown, but this can be changed in the drop-down menu, where you can decide to show up to 100 entries per page.
Carry-over from previous years are included in the quota numbers, where applicable.
You can find the full catch database with all species here.
For any questions regarding the catch database, please contact the Secretariat at email@example.com.
Hunting methods in NAMMCO countries
People’s right to hunt and utilise marine mammals is a firmly established principle in NAMMCO, and hunting conditions and techniques have always been priority issues. Embedded in this right is also an obligation to conduct the hunt in a sustainable way and in such a way that it minimises animal suffering’ (NAMMCO 2010a).
Besides annual hunting quotas, a number of regulations have to be met for bowhead whale hunting to be legal in West Greenland. Hunters are required to hold a valid full-time occupational hunting license, a species-specific license, an approved harpoon gun, and mandatory fishing gear to be allowed to take part in the bowhead whale hunt. Furthermore, hunters have to have attended a course in the use of ‘whale-grenades’ to be allowed to buy and handle those grenades. The hunter that holds the bowhead-license also has to report his plans for the hunt of the bowhead whale to the authorities.
The bowhead whale can only be hunted between April 1st and December 31st. Only adult whales can be taken and calves as well as females with calves are fully protected. The actual bowhead whale hunt requires three whale hunting boats of at least 11 m. Mandatory hunting gear on the boats includes a harpoon gun (calibre of at least 50 mm with approved whale grenades for large whales) and a line or trawl winch with a tractive force of at least five tonnes. Furthermore, the boats have to be equipped with buoys that prevent the whale from sinking. A wounded bowhead whale has to be put down using a ‘whale-grenade’ shot to the breast-region.
Once killed, the whales have to be flensed at a located approved by the authorities. All parts of the whale also have to be used. If there’s too much meat for the hunters themselves to use or sell, the remaining meat must be given to the local community.
Furthermore, the catch has to be reported to the authorities before it can be sold and a tissue sample delivered to the local authority. There can also be regulations regarding where it is allowed to hunt whales and where only whale-safaris can take place (Government of Greenland 2016).
Past and current hunt
A tragic whaling history
The need for blubber, meat, oil, bones, and baleen started the European hunt for whales in the Arctic region. The bowhead whale, a fat, slow swimmer that floats after death, was an ideal target for the European, and later American, whaling ships to exploit. The original or ‘traditional’ form of commercial whaling was distinct from ‘modern’ commercial whaling, which was characterised by fast, motorised vessels with harpoon guns. The exploitation of the bowhead whale precedes the era of modern commercial hunting and ended in the early 1900s (Ross 1993).
The start and subsequent expansion
Whaling for bowhead whales, also called the Greenland whale, polar whale or simply whale at the time, began off the southern coast of Labrador around 1540. As the whaling for bowheads in this area levelled off towards termination in the early 1600s, bowhead whaling started near Spitsbergen. The whaling activities continued and by the year 1700, had expanded into the Davis Strait region and into Hudson Bay in 1860. By the late 19th century, when whaling was in its last phase, whalers were hunting bowhead whales throughout the North Atlantic sector. In the 19th century, American whalers went for the bowhead whales in the Sea of Okhotsk and the Bering, Chukchi, and Beaufort seas (Ross 1993). The hunt for bowhead whales thus continued over almost four centuries at levels driving the bowhead stocks close to extinction.
Estimating the total catch
It has been estimated that since 1530, 70,000 bowhead whales were landed in Eastern Canada and West Greenland – a figure that combines commercial and Inuit hunts using data from revised previous catch series (Higdon 2010). This estimate is without struck-and-lost animals. To maintain the overall killed whales, struck-and-lost animals ought to be added (struck-and-lost rates of 15–20% have previously been used by Mitchell (1977)).
In 1931, the League of Nations Convention protected the bowhead whale from commercial whaling. Some limited subsistence whaling was still carried out by Inuit in Alaska though. In 1946, the International Whaling Commission (IWC) was established by the International Convention for the Regulation of Whaling. The IWC continued the prohibition on commercial whaling started in 1931 and began to regulate commercial whaling among signatory nations in 1964. In 1977, the IWC called for a ban on the increasing subsistence bowhead whaling in Alaska due to concerns about the status of the whale populations. A ban was not implemented, but the IWC did grant a limited quota (Reeves & Leatherwood 1985).
Stock sizes prior to commercial whaling
Several attempts at estimating pre-exploitation stock sizes of bowhead whales have been performed. Historical records and population models (often in combination) have been used for these attempts. However, such estimation is a difficult exercise due to a lack of both a complete catch record and basic information on biological parameters.
Woodby and Botkin (1993) have estimated the pre-exploitation stock size for the Spitzbergen stock to be 25,000, Davis Strait 11,000, Hudson Bay 575, Bering Sea 18,000 and the Okhotsk Sea 6,500. In 2006, Allen and Keay reconstructed the Greenland-Spitzbergen bowhead population throughout the period of commercial exploitation by European whaling vessels (1611–1911). The estimate of approximately 52,500 adult bowhead whales resident in the waters between the east coast of Greenland and Spitsbergen in 1611 was calculated using species-specific biological parameters, a delayed-difference recruitment model, and historical whaling records. The estimate of Allen and Keay (2006) was more than double of the previous estimate from Woodby and Botkin (1993). Also Higdon (2010) suggests that using his revised catch series would improve estimates of pre-exploitation population size over previous attempts.
These few examples give an indication of the complexity of estimating pre-exploitation stock sizes of commercially hunted whales. Regardless of the exact size of the pre-exploitation population, there is no doubt that there were numerous bowhead whales in the Arctic and sub-Arctic waters prior to the start of the whaling era. The removal of that many large marine mammals in a fairly short period of time can be assumed to have had an enormous impact on the Arctic ecosystems (Allen & Keay 2006).
Acoustic pollution is one of the new ‘threats’ facing bowhead whales. Anthropogenic noise in Arctic waters is increasing as human activity increases as a consequence of climate change. Lesser sea ice and an extended open-water season expand the possibilities for exploration and exploitation for oil and gas in the Arctic region. An increase in shipping and shipping routes in otherwise previously impassable regions is also expected. In addition, noise from military activity (e.g. sonar), helicopters and airplanes, and marine constructions add to the overall acoustic load now present in Arctic waters, which were previously largely devoid of anthropogenic noise.
As marine mammals rely heavily on both hearing and producing sounds for a number of vital behaviours like communication and navigation, prey detection, predator avoidance, and mate selection, any increase in underwater sound levels can affect these important functions (Blackwell et al. 2015).
Bowhead whales have been seen to decrease their calling rates during autumn migration in the Alaskan Beaufort Sea when they were in proximity to seismic operations. When sound levels were above a certain threshold, the whales were virtually silent. The effects on the animals from such a change in behaviour are unknown (Blackwell et al. 2015).
CLIMATE CHANGE AND ANTHROPOGENIC IMPACTS
Reductions in sea ice as a consequence of climate change will likely have negative effects on some marine mammals, for example, seals that give birth to pups on ice. However, the reliance of the ice-associated whales on sea ice-mediated ecosystems is unclear (Laidre et al. 2008, Moore and Huntington 2008). Reductions in sea ice may actually enhance feeding opportunities for bowhead whales on prey both produced in and/or advected to their summer and autumn habitats (Moore & Laidre 2006). Despite roughly two decades of sea ice loss in the Alaskan Beaufort Sea, the Bering-Chukchi-Beaufort population has increased steadily at a growth rate of 3.4%, suggesting that sea ice reduction is not hindering recruitment to this population as it rebounds from overhunting during commercial whaling (George et al. 2004). Anticipated changes for the bowhead whale populations could, however, include migration alteration and occupation of new feeding areas (Moore & Huntington 2008).
Although bowhead whales may benefit from lesser sea ice through increased access to prey, the bowhead whales face a growing number of anthropogenic threats as the Arctic becomes more accessible for humans. The impact on bowhead populations of potential risks like oil spills, collisions with ships, increased ocean pollution, emissions from mining activities etc. remain, for now, uncertain.
Research in NAMMCO member countries
Bowhead whales are the subject of extended research activities in both Greenland and Norway. This includes photo identification work (Heide-Jørgensen & Finley, 1991), satellite telemetry studies (Heide-Jørgensen et al. 2003, 2006, 2012a, Lydersen et al. 2012), acoustic analyses (Stafford et al. 2012, Tervo 2009, 2011, 2012a,b), genetic research (Borge et al. 2007, Rekdal et al. 2015, Keane et al. 2015) and studies on age and reproduction (Heide-Jørgensen et al. 2012a). This work has expanded our knowledge of bowhead whale migration patterns, stock structure, behaviour and life-history. Surveys (Boertmann et al. 2015, Heide-Jørgensen et al. 2007, Wiig et al. 2007) have also added to our knowledge through creating estimates of abundance.
RECENT AND ONGOING STUDIES
Rekdal et al. (2015) used two different methods for estimating abundance and trends of bowhead whales in Disko Bay, West Greenland: aerial survey and genetic mark-recapture approach. They found that the two abundance estimates were complementary. The aerial survey provided a snapshot that is useful for examining the local trend without dependence between years. The genetic mark-recapture approach estimates the size of the actual source population, but this approach is considered less suited for time series estimates as it would require samples over many years. The authors concluded that although the two approaches do not necessarily lead to identical estimates, in combination, they give valuable insight into trends affecting abundance and the fraction of the population that is present within the surveyed area (Rekdal et al. 2015).
Long-term studies of bowhead whales in Disko Bay are ongoing. In 2018 and 2019, these studies focused on testing technology for combining satellite telemetry and recording sounds on the surface of whale bodies, in order to better understand the effects of noise from seismic air guns. Oceanographic tags that record temperature, salinity, depth and position are also under development (National Progress Report Greenland 2019). The focus for 2020 is on the collection of biopsy samples for mark-recapture abundance estimates (National Progress Report Greenland 2020).
In 2019, hunters from Qeqetarsuaq collected biopsies of bowhead whales during spring in Disko Bay. These will be used by the Greenland Institute of Natural Resources for mark-recapture abundance estimates (National Progress Report Greenland 2018, 2019).
Boertmann et al. (2015) took advantage of an aerial survey for walrus (Odobenus rosmarus) in part of the Northeast Water Polynya (NEW) and observed several bowhead whales, resulting in an abundance estimate of 102 (95 % CI: 32–329) individuals. The otherwise fairly inaccessible area has only recently been visited by researchers. The authors concluded that the NEW might be one of the most important summering grounds for the Spitsbergen stock and proposed that their results provide renewed hope that this stock was recovering from depletion due to commercial whaling (Boertmann et al. 2015).
In 2018, the Norwegian Polar Institute deployed satellite tags on 9 bowhead whales in the Fram Strait and collected biopsy samples for genetic studies from 2 individuals (National Progress Report Norway 2018). In both 2019 and 2020, 1 satellite tag was deployed, with one biopsy collected from the same individual (National Progress Report Norway 2019,2020). Acoustic recorders were deployed at various locations in the Svalbard area in 2018 (and serviced and redeployed annually since then), with the main objective of listening for bowhead whales, belugas and narwhals (National Progress Report Norway 2018,2019,2020).
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