Updated: August 2020
The narwhal is a medium-sized toothed whale that belongs to the family Monodontidae. The only other member of this family is the beluga. Narwhals have stout, torpedo-shaped bodies with a low dorsal ridge in place of a dorsal fin, and a concave-shaped tail fin. Like belugas, narwhals have short paddle-shaped front flippers, but they lack their extremely flexible neck and well-defined beak. At birth, narwhals are grey to greyish-blue in colour. They become darker and more mottled as they grow older, with white patches developing from their abdomen to up over their backs. Adult narwhals are usually light grey in colour, with a mottled pattern of darker markings over a lighter background. Very old narwhals become almost completely white. Male narwhals develop a tusk, which is a modified canine tooth that grows out the left side of the jaw, twisting anti-clockwise to form a spiral.
An approximate estimate of global abundance is 85,000 – 100,000 animals (NAMMCO 2017).
Narwhals are found in Arctic waters in areas that are seasonally ice-covered. They are found in the northern waters of Canada, Greenland, Norway and Russia.
Narwhals are hunted for their tusks and for food throughout their range. In the past, there was also some commercial harvest in some areas.
There is an international management regime under the Joint Commission for the Conservation and Management of Narwhal and Beluga (JCNB) and NAMMCO. In West Greenland, hunting quotas have been introduced and present harvests are within sustainable limits. Narwhal in Northeast Greenland are protected within the boundaries of the world’s largest National Park. In East Greenland, narwhal aggregations are considered to be small, depleted and declining. Noting this, as well as the impacts of climate change on the species, in 2019 the NAMMCO Scientific Committee recommended that catches in all management areas in East Greenland be reduced to zero.
In the most recent assessment (2017) the species is listed as being of ‘Least Concern’ on the global IUCN Red List.
Scientific name: Monodon monoceros
Greenlandic: Qilalugaq qernertaq
The English name “narwhal” is derived from the Old Norse word ‘nar’ which means ‘corpse’, perhaps in reference to the animal’s grey colour, thought to resemble that of a drowned sailor (Heide-Jørgensen and Laidre 2006).
Adult male narwhals reach lengths of up to 460 cm and weights of 1645 kg, while females are smaller at up to 400 cm and 900 kg. The tusk of a male narwhal can exceed 2 m in length.
On average, female narwhals have one calf every 3 years. They reach sexual maturity between 7 and 9 years of age.
Narwhals spend their entire lives in cold Arctic waters. They are almost always associated with sea ice, except during late summer in some areas.
Narwhals feed primarily on fish and squid, particularly polar cod (Boreogadus saida), Arctic cod (Arctogadus glacialis), Greenland halibut (Reinhardtius hippoglossoides) and squid of the genus Gonatus.
Narwhals can live for more than 100 years.
The narwhal is a medium-sized toothed whale that belongs to the family Monodontidae. The only other member of this family is the beluga. Narwhals have stout, torpedo-shaped bodies with a low dorsal ridge in place of a dorsal fin and a concave-shaped tail fin. They lack the extremely flexible neck and well-defined beak of their closest relative, the beluga. Like the beluga, the narwhal has short paddle-shaped front flippers.
At birth, narwhals are grey to greyish-blue in colour. They become darker and more mottled as they grow older, with white patches developing from their abdomen to up over their backs. Adult narwhals are usually light grey in colour, with a mottled pattern of darker markings over a lighter background. Very old narwhals become almost completely white.
Male narwhals develop a tusk, which is a modified canine tooth that grows out the left side of the jaw, twisting anti-clockwise to form a spiral. Occasionally male narwhals have two tusks and a small percentage of females also have a tusk.
Watch a video discussing the possible functions of the narwhal's tusk
The narwhal is a medium-sized toothed whale, with males reaching a maximum length of about 460 cm and a maximum weight of 1,645 kg, with females slightly smaller at 400 cm and 900 kg (NAMMCO 2013, Garde et al. 2007). Narwhals are very long-lived animals. Recent research looking at chemical changes in the eye lens has demonstrated that narwhals can live for more than 100 years (Garde et al. 2007). This makes the narwhal the longest-lived of the toothed whales and one of the longest-lived of all mammals.
The narwhal reaches sexual maturity between the ages of 7 and 9. They mate from late May to early June and calves are born about a year later, during the time the animals are migrating towards their summering areas. On average, narwhals have a single calf every 3 years throughout their lifetime (NAMMCO 2013, Garde et al. 2007).
The Unicorn of the sea
The most distinguishing feature of the narwhal is the male’s long tusk, which has led them to be called the “unicorn of the sea”. The tusk is actually a modified canine tooth. Usually only one tusk erupts from the left side of the upper jaw, but a small percentage of male narwhals have a tusk on both sides of the jaw. Other than the single tusk, narwhals are toothless. The tusk is spiral in form, almost always in an anti-clockwise direction. In some narwhals the tusk may exceed 2 m in length (NAMMCO 2013, Garde et al. 2007).
Narwhals feed primarily on fish and squid throughout their range. Both the diet and the intensity of feeding vary seasonally.
During the summer, narwhals apparently feed very little; hence the stomachs of narwhals harvested at this time of year are usually empty. They begin to feed more heavily in the autumn during migration and especially during the winter at their deep-water wintering grounds. In Baffin Bay, the winter diet is dominated by the Greenland halibut (Reinhardtius hippoglossoides) (Laidre and Heide-Jørgensen 2005b). To access this bottom-dwelling species, narwhals must make repeated dives to depths of between 800 and 1,600 m. Each dive takes up to 25 minutes, with about half of that spent near the bottom (Laidre et al. 2003, 2004).
Arctic cod (Arctogadus glacialis), polar cod (Boreogadus saida) and squid of the genus Gonatus also form an important part of the winter diet. These species may be available in mid-water in areas too deep for narwhals to reach the bottom (Laidre et al. 2003, 2004, Laidre and Heide-Jørgensen 2005b). During the spring, as narwhals follow the retreating ice edge, polar and Arctic cod become more important in the diet (Laidre et al. 2004).
Like all toothed whales, narwhals use echolocation to find prey. This is particularly important for a species that does most of its feeding in very deep waters during the long nights of the Arctic winter. A recent study in which a camera was attached to free ranging narwhals demonstrated that narwhals spend a high proportion of their time upside down while diving and swimming at the sea bottom (Dietz et al. 2007). This may allow them to better project their echolocation clicks to locate prey, and perhaps also to protect their lower jaw and tusk from contact with the bottom.
Importance as predators
There have been some attempts to determine the importance of narwhals as predators by modelling how much fish they consume. Laidre et al. (2004) used a bioenergetic model to estimate the biomass of Greenland halibut needed to sustain narwhals during the five months that they spend at their wintering grounds. Estimates were made for varying levels of Greenland halibut in the narwhal diet: 25%, 50% and 75%. Assuming a diet comprised of 50% Greenland halibut, the 32,000 narwhals in the southern overwintering area would eat approximately 576 tonnes per day, or about 86,000 tonnes of Greenland Halibut for the five-month winter period (DFO 2014). The area classified as the northern over-wintering ground supports a larger number of whales (approx. 45,000) and was estimated to require 700 tonnes per day with a mean consumption over five months of 110,700 tonnes (95% CI of 53,000 t – 310,300 t) (DFO 2014, DFO 2007). This amount is, however, larger than the estimated biomass of Greenland halibut in that area, suggesting that narwhals in this area make greater use of other prey species.
Underwater video of narwhals swimming
Narwhals show sexual dimorphism, with several differences between males and females. Adult male narwhals are on average longer and heavier than females, reaching a maximum length of about 460 cm and a maximum weight of 1,645 kg. Adult females have a maximum length of 400 cm and weight of 900 kg (NAMMCO 2013, Garde et al. 2007).
The other obvious difference between the sexes is the presence of the tusk in males. While a small percentage of females may also have a tusk (roughly 6% of tusked narwhals in the Canadian Inuit harvest were females (Petersen et al. 2012)), it is a feature found in all adult males. The tusk is actually a modified canine tooth, and is in fact the only tooth these whales possess. Usually, only one tusk erupts from the left side of the upper jaw, but in a small percentage of male narwhals a second tusk erupts from the right side of the jaw. The tusk is spiral, almost always in an anti-clockwise direction (NAMMCO 2013, Garde et al. 2007).
Recently Nweeia et al. (2014) suggested that the tusk may have another function altogether – as a sensory organ. The tusk is innervated and small channels in the tusk put the inner, pulpy core of the tusk in contact with the marine environment. A tusked (usually male) narwhal may therefore be able to directly sense changes in the marine environment, such as variations in salinity and temperature, through its tusk. This may aid in navigation and in avoiding being caught in rapidly freezing seas. Nevertheless, it is difficult to explain why only male narwhals would have evolved or retained this capability.
PREDATION AND OTHER NATURAL THREATS TO THE POPULATION
Apart from man, the main predator of the narwhal is the killer whale. Narwhals react to the presence of killer whales by moving close to land or sea ice, and forming tight groups. They may move into very shallow water and even occasionally become beached (Laidre et al. 2006).
Because of their association with heavy ice cover, narwhals are vulnerable to becoming trapped in ice if high winds move ice around or the temperature drops suddenly. Narwhals require leads or open areas in the ice to breathe, since they are unable to open or maintain a breathing hole through thick ice. A cetacean entrapment in ice is called a savsaat in Inuktitut, and is a relatively common if unpredictable occurrence. Such entrapments may be a major source of natural mortality for narwhals (Heide-Jørgensen et al. 2002). Many of these events probably go undetected, especially if they are small and in a remote location.
A savsaat in 2008 in Eclipse Sound saw more than 600 narwhals entrapped. 629 narwhals were harvested from the savsaat, but more animals may have drowned (DFO 2008). Such a large entrapment of animals is rare in Nunavut, having been recorded only once before in the previous century (Heide-Jørgensen et al. 2002).
Watch a video of killer whales attacking a pod of narwhals
Distribution and Habitat
The narwhal is one of three species of whales (along with beluga and bowhead whales) that spend their entire lives in cold Arctic waters. They are perhaps the most “Arctic” of whales, being found exclusively in areas of the Arctic that are seasonally covered by land-fast or pack ice. Narwhals can be found further north and in areas that are inaccessible to other Arctic whale species. They are almost always associated with sea ice, except during late summer in some areas.
During the autumn, winter and early spring, the narwhal lives in dense pack ice, using leads and polynyas (open water areas within pack ice) to breathe. In the spring, narwhals follow the receding pack ice and spend the summer usually in shallower waters closer to land, often within fjords or close to glacier fronts.
Much has been learned about the physical and seasonal habitat of narwhals through the application of satellite-linked tags. In such studies, narwhals are captured in nets and the tags are attached either to the tusk (in male narwhals) or by bolts through the dorsal ridge. The tags transmit data when the narwhal surfaces. Along with location, tags can collect data on diving and the time spent at specific depth intervals. To date, tagging studies have been conducted on almost all summer aggregations of narwhals in Canada and Greenland (Heide-Jørgensen et al. 2013b) and in Svalbard (Lydersen et al. 2007). Read more in Section 11: Research in NAMMCO member countries.
Narwhals begin migrating as early as late March or early April, following the receding pack ice into areas inaccessible in the winter. At this time of year they can be found at ice edges in the Canadian Eastern Arctic, West and East Greenland and Svalbard. Narwhals tend to spend more time near the surface and travel farther each day during the spring (Laidre et al. 2004).
During the summer, narwhals can be found closer to land and in shallower water than at other times of the year (Laidre et al. 2004, Heide-Jørgensen et al. 2013ab). They move into areas of the Canadian Eastern Arctic, West and East Greenland and Svalbard that are covered by landfast ice and therefore inaccessible at other times of the year. During this period, narwhals often congregate in fjords and at glacier fronts. They also form larger groups than during other periods, up to several hundred animals.
Their return to wintering areas begins in late September or later, depending on when the sea ice begins to form. Autumn movements are often quite rapid although narwhals may occupy other coastal areas that remain ice-free for periods at this time of year (Heide-Jørgensen et al. 2013ab). They reach their wintering grounds by November or early December.
The general pattern of seasonal habitat use is similar for all populations that have been tracked so far. During the winter, narwhals occupy areas covered with heavy pack ice over water up to 2,000 m in depth. In Baffin Bay they spend the winter in areas with as little as 0.5% open water (Laidre and Heide-Jørgensen 2005a), diving repeatedly to depths down to 1,600 m to feed on fish at or near the sea bottom. Narwhals are physiologically adapted for long dives, having a very high ratio of slow oxidative to fast twitch muscle fibres, and by having the highest levels of myoglobin recorded in any marine mammal, giving them exceptional oxygen storage capacity (Williams et al. 2011). They can dive aerobically for up to 24 minutes, giving them the ability to feed at great depths and move up to 1.4 km between breathing holes.
A “stock” of animals is a term often used in wildlife management. The stock is the basic unit of management, mainly because it describes a group of animals that is reproductively and often physically isolated from other groups. Animals in a stock generally share similar life history characteristics, such as age of sexual maturity, rate of breeding etc. Most importantly, animals within a stock mate and breed primarily with other members of that stock.
It is important to try to determine whether narwhals are all members of one stock, or if there are different stocks, for a number of reasons. Narwhals are hunted throughout Nunavut in Canada and in Greenland. In order to set appropriate harvest levels, managers need to know if narwhals are being taken from one or more stocks, and which stocks those are. It is also important to know if there are different stocks in order to make sound population estimates.
Stock identity is determined in various ways: through analyzing the genetic makeup of individuals, tagging studies, studies of stable isotope ratios, use of traditional ecological knowledge, and studies of morphology.
Genetic studies, stable isotope analysis, and morphology
In general, narwhals appear to have low genetic diversity and there is little differentiation among stocks (NAMMCO 2013). There are two possible reasons for this: either a “bottleneck”, or population restriction, occurred at some point in the distant past, or there is currently a high rate of gene flow between areas. Either or both explanations could be correct.
Despite this overall low genetic diversity, genetic studies have found that narwhals in East Greenland are distinct from those in West Greenland, as well as from those around Svalbard (NAMMCO 2013; NAMMCO 2019). Within West Greenland, far northern (Uummannaaq) narwhals are different from those found further south. Differences are also seen between Baffin Bay, Northern Hudson Bay and East Greenland populations (Petersen et al. 2011, NAMMCO 2013). Less distinct differences have also been found between narwhals that summer in Jones Sound and the Somerset Island area (Petersen et al. 2011).
Similar results have been found using stable isotope analysis of carbon and nitrogen from skin samples. In this analysis, a clear difference was seen between northern Hudson Bay, East Greenland, and all other stocks (Watt et al. 2012b).
East Greenland narwhals are also distinct in their cranial morphology (Wiig et al. 2012a). However, no differences were seen between West Greenland and Canadian narwhals.
Contaminant level analysis
Another method that has been used to try to identify stocks is analysis of organochlorine (OC) contaminant levels in narwhal tissues. Differences in contaminant levels can be caused by differences in feeding, which may depend on prey selection, feeding patterns in summering/wintering areas or on migration routes, and in the feeding behaviour of the individual. In a 2003 study using this approach, narwhals sampled from Repulse Bay could be distinguished from all other narwhals studied. Apart from that group, it was not possible to clearly distinguish other stocks using this method (de Marche and Stern 2003).
Tagging studies have been conducted in a number of locations throughout the narwhal’s range. These studies suggest interannual site fidelity, which means that narwhals generally return to the same summering and wintering areas year after year. There are, however, exceptions to this rule. One narwhal tagged in Admiralty Inlet wintered in Northern Foxe basin rather than Davis Strait (Watt et al. 2012a, NAMMCO 2013), and one whale tagged in northern Greenland migrated to Somerset Island in the summer (Heide-Jørgensen et al. 2013).
Most narwhal stocks from northern Canada and West Greenland mix in the winter in Baffin Bay/ Davis Strait (Heide-Jørgensen et al. 2013). Mating, however, occurs during the spring migrations to the summering areas, which maintains summer stock identity (NAMMCO 2013).
The “summering aggregations” (areas where narwhals are found in the summer) currently provide the basis for the determination of management areas. This is primarily because: 1) narwhal stocks tend to be geographically isolated during the summer, and 2) because it is during the summer and at these locations that narwhals are usually hunted. The Global Review on Monodontids (NAMMCO 2018, Hobbs et al. 2019) recognised seven stocks in Canada, two in West Greenland, two in East Greenland and one in Svalbard-Northwest Russia (NAMMCO 2018).
The stock structure in East Greenland remains unclear though and particularly the question of whether one or two populations are inhabiting the area around Ittoqqortoormitt/Scoresby Sound at different times of the year (NAMMCO 2019). Additional tagging studies are planned to further investigate and clarify stock structure in East Greenland. Currently it is considered to be one stock, but is divided into three management areas to support a precautionary approach (see below for more information).
Svalbard and Northwest Russian Arctic
There is very little information on the narwhals that inhabit this area. Generally narwhals were historically sighted and sometimes caught by Norwegian sealers and whalers in the area between East Greenland, Svalbard, the New Siberian Islands and Novaya Zemlya (Gjertz 1991, Lydersen et al. 2007). Narwhals are most frequently observed in the northwest and northeast parts of the Svalbard archipelago, but this probably reflects the numbers of observers rather than the number of animals. Generally, narwhals in this area appear to be widely dispersed and do not form large predictable aggregations as they do in other areas. The wintering area of Northeast Atlantic narwhals is not known, but it is likely that they overwinter within the extensive pack ice in this area. Farther east, sightings of narwhals are very rare or non-existent.
During the summer, narwhals are found along the East Greenland coast with concentrations found in the areas around Scoresby Sound, Tasiilaq and Kangerlussuaq (Heide-Jørgensen et al. 2010, NAMMCO 2017). Narwhals have a scattered distribution along the coast and periodically occupy many fjords in the area. Although narwhals in East Greenland are currently recognised as a single stock (NAMMCO 2018), the possibility that two populations are inhabiting the area of Scoresby Sound/Ittoqqortoormiit is currently being investigated. The NAMMCO-JCNB Joint Working Group (see “Management”), the NAMMCO Scientific Committee, and the NAMMCO Management Committee for Cetaceans all recently agreed to recognise three separate “management units” in East Greenland in order to adopt a precautionary approach to providing management advice and minimise the potential for local depletions. The three management areas now recognised for narwhals in East Greenland are: Tasiilaq (south of 67°N), Kangerlussuaq (68°30’N to 67°N), and Ittoqqortormiit (Scoresby Sound and Blosseville Coast south to 68°30’N).
Narwhals are frequently found north of Scoresby Sound and as far north as Nordøst Rundingen – 82°N (Boertmann and Nielsen 2009 and 2010). Given the long coastline, it is possible that there are several stocks in Northeast Greenland. However, there is currently very little available data to determine stock structure with confidence (NAMMCO 2018). Narwhals may also occur between Greenland and Svalbard but there is little supporting data for this.
West Greenland (Inglefield Bredning and Melville Bay stocks)
Narwhals are found off West Greenland at all times of the year. Two stocks occur in summer aggregations at Inglefield Bredning and Melville Bay. During the autumn, winter and spring they are found in the ice pack off the West Greenland coast from Smith Sound to just south of Disko Bay (Heide-Jørgensen et al. 2010). While the summering aggregations are considered to be stocks for management purposes, at other times of the year, narwhals off West Greenland are likely composed of a mixture of animals from several summering areas, including stocks that summer in Canada (Heide-Jørgensen et al. 2012).
There are seven stocks/summer aggregations of narwhals in Canada.
The North Hudson Bay narwhals summer in northwestern Hudson Bay, particularly near Repulse Bay and into Foxe Basin. Tagging studies indicate that this group winters in the pack ice at the eastern end of Hudson Strait (DFO 2010a, Heide-Jørgensen et al. 2012). The Northern Hudson Bay stock can be separated from other Canadian stocks through genetics, contaminant analysis and by the fact that its distribution does not overlap with that of any other group of narwhal.
The six other Canadian stocks (Somerset Island, Jones Sound, Smith Sound, Eclipse Sound, Admiralty Inlet, and East Baffin Island) winter in southern Baffin Bay/northern Davis Strait and have summer concentrations throughout the eastern Canadian Arctic Archipelago. These stocks are considered “shared stocks” with Greenland, as they migrate into Greenlandic waters seasonally. Tagging studies have indicated that there is little mixing between areas during the summer, although it does sometimes occur.
The distribution of all these stocks, and the two stocks in West Greenland, overlaps in the winter and not surprisingly they cannot be readily differentiated genetically or by other means. Nevertheless, these divisions are useful for management purposes as it allows a stock allocation to hunting areas, which is a more conservative and precautionary approach than assuming that there is only one “panmictic” stock of narwhals in the area. This is because the latter approach could result in local depletions if an underlying stock structure did exist.
Estimating the abundance of narwhals is difficult due to the remoteness and large size of their distribution area, the mobility of the animals, and their close association with sea ice. Aerial surveys are most commonly used. However, the results must be corrected for both whales that are at the surface but missed by observers, and those that are below the surface/out of sight when the survey airplane is overhead. Another problem is that direct comparisons between surveys are not always possible, since surveys rarely have the same timing or cover the same area.
A rough estimate for the total world population is 85,000 – 100,000 animals (White 2012, NAMMCO 2017). A more detailed breakdown of the population status in different areas of the Arctic is given below.
Svalbard-Northwest Russian Arctic
There has not yet been a survey around Svalbard specifically targeting narwhals. However, a multi-species survey in the marginal ice zone north of Svalbard in August 2015 resulted in an estimate of 837 narwhals (CV = 0.50) (Vacquié-Garcia et al. 2017). This is likely a minimum estimate as the survey did not cover all of the area where narwhals may occur. There are no previous abundance estimates to compare with this 2015 estimate so it is not possible to say anything about trends for this stock.
Information on narwhal sightings in the northwestern Russian Arctic (Barents and Kara Seas) comes mostly from the annual National Park “Russian Arctic” monitoring program, as well as opportunistic observations during oil/gas geological explorations, scientific expeditions, and tourist cruises. There is no abundance estimate for narwhals in this region.
The East Greenland stock of narwhals occurs along the coast from about 64°N to 72°N and is divided into the three management areas of Scoresby Sound/Ittoqqortoormiit, Kangerlussuaq and Tasiilaq (see section on North Atlantic Stocks). Aerial surveys have been conducted around the hunting grounds in Scoresby Sound in 1983-84 and 2017, and from Tasiilaq to Scoresby Sound in 2008 and 2016. The NAMMCO Ad Hoc Working Group on Narwhal in East Greenland reviewed data from all of these surveys and applied correction factors for perception and availability bias to the abundance estimates, including retrospectively to the initial estimates from the 1983 and 1984 surveys (Larsen et al. 1994). The corrected abundance estimates from all currently available surveys in East Greenland are presented in the table below.
The area north of Scoresby Sound is a National Park. It is the largest protected area in the world and includes protection of the sea up to 3 nautical miles from the shoreline. Northeast Greenland is therefore not part of the hunting grounds for narwhals, although narwhals from this area may be supplying the hunt in regions further south. The Northeast Water polynya can be an important habitat in winter. There is however little documentation of the population abundance and distribution in this area. A dedicated aerial survey was conducted in Northeast Greenland (covering the Northeast Water polynya) in March/April 2017. Narwhals were detected twice during this survey and no abundance estimation was made on this low sighting rate.
Summer surveys were carried out in parts of the Greenland Sea in August/September 2017. There were 15 sightings of narwhal during this survey, concentrated in the coastal area north of Dove Bay, but this has not generated an abundance estimate. Surveys were also carried out in Dove Bay in August/September 2017 and September 2018, both of which indicated a high density of animals. Minimum abundance of individuals summering in Dove Bay was estimated as being 1100 animals in 2017 and 700 in 2018, (fully corrected estimates = 2297 and 1395 animals respectively) (Hansen et al. 2019). Due to the late ice break up in Dove Bay in 2018 (only a few days prior to survey), it is possible that individuals that spent the summer in the Bay the year before were further off shore or even relocated to another fjord system that was ice free at the time of the 2018 survey.
Aerial surveys were conducted over the eastern part of the North Water polynya in April 2014. The resulting estimates suggested that 3059 narwhals (95 % CI: 1760–5316) wintered in the eastern part of the North Water polynya during this time (Heide-Jørgensen et al. 2016). Narwhals sightings were also recorded during a 2018 multi-species survey of the North Water, with 23 narwhal sightings recorded.
Migration patterns for this stock are unknown but a portion of the whales that winter in the North Water polynya could be the same narwhals that summer in Inglefield Bredning (see abundance estimate above).
The most recent abundance estimate for the Inglefield Bredning stock comes from a 2007 survey, with a fully corrected estimate of 8,368 narwhals (95% CI: 5209 – 13,422)(Heide-Jørgensen et al. 2010). Previous surveys conducted in 1985-1986 and 2001-2002 have used different methods and covered different areas, so the abundance estimates are not directly comparable to allow for determination of trend (Born et al. 1994; Heide-Jørgensen 2004). The distribution seen in 2007 was, however, similar to past surveys (Heide-Jørgensen et al. 2010).
Melville Bay was last surveyed in 2014 and the corrected estimate was 3,091 animals (95% CI: 1,228 – 7,783) (Hansen et al. 2015).
The wintering area in eastern Baffin Bay along the West Greenland coast was most recently surveyed in March-April 2012, as part of a long-term series of surveys conducted 7 times since 1981. The survey resulted in a corrected estimate of 18,583 narwhals (95% CI: 7,308–47,254). Aggregations of narwhals were seen clumping at the sea ice edge, probably due to bathymetric features in this area. Numbers here seem to fluctuate from year to year, probably because of annual variations in ice conditions in the area, as well as variations in the timing of seasonal migrations. This result is a large increase in the abundance from the previous survey in 2006, which was 7,819 narwhals. This is likely because the 2012 survey covered a larger survey area, especially in the north part of the area where 1/3 of all the animals were seen. This area had not been previously surveyed.
A comprehensive survey with narwhals as the main target species was carried out in Canadian waters in August 2013 and abundance estimates for most stocks have been developed from this survey. The survey covered all major known summer aggregation areas for Baffin Bay narwhals in Canada, including Peel Sound, Prince Regent Inlet, Admiralty Inlet, Eclipse Sound and the East Baffin Coast. Jones Sound and Smith Sound were surveyed for the first time. This was the largest aerial survey ever carried out in Canada, with three planes and 15 observers taking part over a four week period. It is also the first time that all major narwhal habitat has been surveyed in a single year.
The most recent abundance estimate for this stock is from the 2013 survey and was 49,768 (CV=0.20), which has been corrected for perception and availability bias (Doniol-Valcroze et al. 2015). This stock has been surveyed in 1981, 1984, 1996, 2002-2004 and 2013, with variable coverage. Based on the data available from the last 30 years, the stock appears to be increasing (NAMMCO 2015, Witting 2016).
The 2013 survey was the only time this stock has been surveyed and resulted in an abundance estimate of 12,694 (CV = 0.33) narwhals, corrected for perception and availability bias (Doniol-Valcroze et al. 2015). Since this is the only survey that has been conducted, it is not possible to determine a trend for this stock.
The survey conducted in 2013 resulted in an abundance estimate for the Smith Sound stock of 16,360 (CV=0.65) narwhals, corrected for perception and availability bias (Doniol-Valcroze et al. 2015). This is the only survey that has been conducted of this area and there is therefore not enough information to determine a trend.
Based on the 2013 survey, the most recent abundance estimate for this stock is 10,489 animals (CV=0.24), corrected for perception and availability bias (Doniol-Valcroze et al. 2015). A previous survey in 2004 resulted in an abundance estimate of 20,230 (CV=0.36), and because of the overlapping confidence intervals from the two surveys, there is no significant change in abundance. With only two surveys, however, a trend cannot be determined.
The 2013 survey resulted in an abundance estimate for this stock of 35,043 (CV=0.42), corrected for perception and availability bias (Doniol-Valcroze et al. 2015). Five surveys of this stock have been conducted over the past 30 years and indicate no significant change in abundance (Richard et al. 2010, Asselin and Richard 2011, Witting 2016).
Eastern Baffin Island
The most recent abundance estimate for this stock is based on the 2013 survey and estimates 17,555 (CV=0.35) animals. A previous survey in 2003 resulted in an abundance estimate of 10,073 (95% CI: 5,333 – 17,474). Both of these estimates have been adjusted for availability and perception bias (Doniol-Valcroze et al. 2015). It is not possible to determine a trend from these two estimates.
North Hudson Bay
This stock has been surveyed in the early 1980s, 2000 and 2011 using different scales, methods and procedures. The most recent survey from 2011 resulted in an estimate of 12,485 narwhals (95% CI: 7,515 – 20,743) (Asselin et al. 2011). However, to provide comparability of estimates from across the different surveys, the 2011 data were re-analysed using the methods of the visual surveys in 1982 and 2000. This yielded surface estimates of 1737 (95% CI: 1002 – 3011) in 1982, 1945 (95% CI: 1089 – 3471) in 2000, and 4452 (95% CI: 2707 – 7322) narwhals in 2011 (Asselin et al. 2012).
Svalbard – Northwest Russian Arctic
There is currently very little information about narwhal abundance, distribution, and stock identity in this area, and therefore it is difficult to assess the status of the stock. The experts at the Global Review of Monodontids (GROM) meeting held in 2017 (NAMMCO 2018, see box to the right) gave a moderate level of concern for narwhals in this area, mainly due to the lack of information available and the likelihood that there is a low abundance. Narwhals are protected in Svalbard and Russia.
In 2017, the NAMMCO-JCNB Joint Working Group, and the Global Review of Monodontids (GROM),be both recognised that the environment in this area is changing rapidly, including increased sea surface temperatures, rapidly retreating ice cover, and disappearance of tidewater glaciers. These changes are resulting in poor and reduced narwhal habitat. In addition, tropical species (including humpback whales) have been observed in the area, which is likely causing competition for prey, exposure to novel diseases, etc. It is difficult to tease apart the impacts from these environmental changes from the hunting pressure in the area.
Reviewing the status of all belugas and narwhals
In March 2017, NAMMCO organised a Global Review of Monodontids (GROM), which discussed the conservation status, threats, and data gaps for all stocks of belugas and narwhals globally. The previous review had been performed almost 20 years ago and a large amount of new information had become available since then, especially on stock identity, movements, abundance, and threats to the populations. Additionally, many new stressors have emerged in the last 20 years, especially related to climate change.
Stock experts representing Greenland, Canada, Alaska, Russia, the Government of Nunavut, Nunavut Tunngavik, Inc., the Inuvialuit Settlement Area and the Nunavik Wildlife Management Board participated in the review.
The report can be found here and a publication is in preparation for peer review.
Given the concerns about a changing habitat for narwhals in East Greenland, the GROM (NAMMCO 2018) stated “There is a high level of concern for narwhals in East Greenland due to the lack of data (particularly on stock structure), low abundance, declining trend, likely overharvest, and the numerous climate-related changes in habitat.” In 2019, NAMMCO convened an Ad Hoc Working Group on Narwhal in East Greenland to review and assess the status of the stock and provide advice on the future sustainability of catches for all three management areas (NAMMCO 2019a).
In management area 1 – Ittoqqortormiit, Scoresby Sound and Blosseville Coast south to 68°30’N – the population assessment model estimated a small and depleted aggregation (down to only 18% of the historical population estimate). With an annual growth rate estimate close to zero, it was deemed unlikely that the aggregation could sustain any current removals (NAMMCO 2019a,b).
In management area 2 – Kangerlussuaq 68°30’N to 67°N – the population assessment model estimated a small depleted aggregation (down to 27% of the historical population estimate). The number of narwhals estimated to be present in this area was considered to be so small that it was unlikely to sustain any current removals. This was particularly the case given that factors that can negatively affect small populations were not considered in the model but needed to be taken into account when determining the sustainability of the harvest (NAMMCO 2019a,b).
In management area 3 – Tasiilaq, south of 67°N – the population model also estimated a small depleted aggregation (down to 25% of the historical population estimate). This aggregation was also considered so small that it could not sustainable any current removals (NAMMCO 2019a,b).
The continued hunting of this small depleted stock, combined with observed impacts from climate change, and possible disturbance from other anthropogenic stressors such as noise, lead to both the Ad hoc Working Group (NAMMCO 2019a) and the NAMMCO Scientific Committee (NAMMCO 2019b) expressing significant concern over the status of this stock.
Narwhals are frequently sighted along the coast north of Scoresby Sound. This area is within the Northeast Greenland National Park (the largest protected area in the world) and no hunting takes place in marine waters along the Park’s boundary. Despite the protection of narwhals in this area, there is moderate concern for this stock due to the lack of information on abundance, distribution, and stock structure, and the climate-related habitat changes already seen to be taking place in the waters south of this area (NAMMCO 2018).
Narwhals that summer in West Greenland are from the Inglefield Bredning and Melville Bay stocks.
The Inglefield Bredning stock is considered to be depleted from its previous abundance, but has been stable since the 1980s (Witting 2016). With the stable abundance and sustainable harvest levels, there is currently low concern for this stock (NAMMCO 2018).
The Melville Bay stock is apparently stable, but is considered to be a small stock for which the current harvest levels exceed the recommendations of the NAMMCO-JCNB Joint Working Group. Therefore, the GROM expressed high concern for this stock (NAMMCO 2017, 2018).
Narwhals that occur in West Greenland during the autumn, winter, and spring are likely from a mix of stocks that include Inglefield Bredning and Melville Bay, but also narwhals that are from the summer aggregations/stocks from Canada (see below).
There are seven stocks of narwhals that summer in Canada, six of which are “shared stocks” with Greenland (i.e., they may migrate into Greenlandic waters and are available to Greenlandic hunters at some point during the year).
Somerset Island, Jones Sound and Smith Sound stocks
The Somerset Island stock is the largest narwhal stock and appears to be increasing. This stock is hunted by multiple communities in Canada and also in Greenland during the migration, but the removals are considered sustainable. Given these factors, there is low concern for this stock (NAMMCO 2018).
The Jones Sound and Smith Sound narwhal stocks are fairly large (about 12,000 and 16,000, respectively), removal numbers are low and sustainable, and there are few habitat concerns. Therefore, there is low concern for both of these stocks (NAMMCO 2018).
Admiralty Inlet and Eclipse Sound stocks
The Admiralty Inlet stock is fairly large and stable, and the hunt is considered sustainable. Although there are habitat concerns related to increasing human activities (including disturbance from freighters, cruise ships and supply vessels) in their summer habitat, the GROM had low concern due to the size and sustainability of the hunts (NAMMCO 2018).
The Eclipse Sound stock appears to be stable at around 10,000 narwhals (although there is considerable uncertainty around the abundance estimate) and removals are considered sustainable. A major and growing concern is ship traffic related to the Baffinland-Mary River iron mine and tourism. Overall, the Eclipse Sound stock of narwhals was deemed to be of moderate concern (NAMMCO 2018).
Eastern Baffin Island and Northern Hudson Bay stocks
The Eastern Baffin Island stock is fairly large and removals relatively low. However, there is moderate concern for the stock due the lack of data on movements and stock structure, and the possibility that several stocks may inhabit the region in summer (NAMMCO 2018).
The Northern Hudson Bay stock of narwhals is separated from the other stocks in both summer and winter. This is the only narwhal stock in Canada that is not shared with Greenland. This is a fairly large stock of around 12,500 animals and the current level of hunting removals is considered sustainable. Although the loss of sea ice and concomitant increases in shipping and other industrial activities are of concern, overall concern for this stock is low (NAMMCO 2018).
STATUS ACCORDING TO OTHER ORGANISATIONS
Narwhals are currently listed on Appendix II of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) (as are all species of cetaceans not listed on Appendix I). CITES is a legally-binding multilateral environmental agreement that aims to ensure that international trade does not threaten the survival of species in the wild. Both Denmark (Greenland) and Norway are signatories to the convention. A listing on Appendix II means that an export permit shall only be granted when the Scientific Authority of the State of export has advised that such export will not be detrimental to the survival of the species in the wild.
On the IUCN “Red list” narwhals are listed as Least Concern in an assessment made in 2017.
Narwhals inhabit the waters of two NAMMCO member states: Norway and Greenland.
Norway does not presently permit the harvest of narwhals in its territory.
Some West Greenland narwhals may travel to Canadian waters, therefore management is a shared responsibility between Greenland and Canada. Greenland and Canada have established a bilateral management body, the Canada/Greenland Joint Commission on the Conservation and Management of Narwhal and Beluga (JCNB). The JCNB has a Joint Scientific Working Group (JWG) together with the NAMMCO Scientific Committee Working Group on the Population Status of Narwhal and Beluga in the North Atlantic. This NAMMCO-JCNB JWG provides advice at the request of the JCNB and NAMMCO, pertaining to such issues as stock delineation, total allowable catches and threats to beluga and narwhal populations. The JCNB Commission meets periodically to receive this advice and provide management advice to Canada and Greenland.
There was concern in the past that West Greenland narwhals were declining in number due to overharvesting. This concern was based on an apparent decline in summer numbers at Inglefield Bredning between 1986 and 2002, and a decline in the numbers seen in winter index surveys conducted in the 1980s and 1990s in Disko Bay (NAMMCO 2006, 2010). However, more recent surveys (Heide-Jørgensen et al. 2010) do not suggest that numbers are in decline and that other factors such as methodological differences between surveys and annual fluctuations in numbers due to ice conditions may have contributed to the previous apparent decline.
In 2012, both the JCNB and the NAMMCO Scientific Committees used recent abundance estimates and other information to conclude that quotas and takes from the summer aggregations at Inglefield Bredning and Melville Bay are sustainable (NAMMCO 2013). In 2017, experts performing the GLobal Review of Monodontids (GROM) suggested that although current removal levels were sustainable, the Inglefield Bredning and Melville Bay stocks were below maximum sustainable yield levels and therefore future harvest levels should be set to ensure an increasing number of narwhals (NAMMCO 2018). The total allowable take for the Inglefield Bredning stock was therefore recommended as 98 individuals per year (2015-2020) to give a 70% probability that the population would increase. The total allowable take for the Melville Bay stock was recommended as 84 individuals per year (in the period 2015-2020) to give a 70% probability that the population size would increase (NAMMCO 2015).
In 2019 the Ad Hoc Working Group on Narwhal in East Greenland (NAMMCO 2019a) expressed concerns regarding a small and declining population experiencing an ongoing harvest and significant habitat changes. On the basis of this, the NAMMCO Scientific Committee recommended there be an immediate reduction to 0 catches in all three management areas of East Greenland, at least until new abundance estimates are generated (NAMMCO 2019b). This recommendation is currently being considered by the NAMMCO Management Committee for Cetaceans, which will make the final determination of the official NAMMCO management advice to the Government of Greenland.
Catch allocation model for shared stocks
Managing a shared stock between two countries can be challenging, especially when that stock of animals migrates. The main problem is how to identify which stock the hunters are taking in various areas in different seasons. The NAMMCO-JCNB Joint Scientific Working Group have developed a model that allows managers to assign catches from the narwhal metapopulation that is shared by Canada and Greenland to the appropriate summering aggregation, by different hunting grounds and seasons. The model includes all information that is available on narwhal movements including telemetry data, all abundance estimates, seasonal occurrence and historical catch data (see examples of the types of information used below). This model is a good example of how two countries can work together to solve a tricky management problem.
Management in Canada
Canada sets harvest levels for narwhals using a “Precautionary Approach Framework” (DFO 2008), which takes a conservative approach to management. As part of this approach, the Potential Biological Removal (PBR) method is used to determine the Total Allowable Harvest. This method was developed in the United States for the regulation of human-induced mortality on marine mammals, and produces a single threshold value for removals from a population, which allows depleted stocks to grow and other stocks to maintain their numbers.
The method produces a total allowable landed catch (TALC) for a narwhal stock, which takes into account whales that are struck and lost by hunters. Hunt loss corrections are derived from annual reports of landed and lost whales from communities under Community Based Management (DFO 2008).
Narwhals have long been a staple food resource for indigenous peoples throughout the Arctic and continue to be an important part of northern diets today. The skin and attached subcutaneous fat is considered a delicacy called muktuk (various spellings and pronunciations, including maktaaq and mattak). The meat varies in quality depending on the cut and is eaten raw, dried or cooked, or used as dog food.
Sometimes the meat and muktuk are aged and prepared in specific ways to make traditional delicacies. The flippers, organs and intestines are also used as food. The skin from the top part of the whale can be cut and prepared to make rope, and the tendons have been used to make sinew for sewing. The blubber can be rendered to oil and used in traditional lamps (qulliq) as a source of light and heat. Even the bones have been used as a food source, construction material and for carving. While many of these uses have been replaced by modern materials, narwhal muktuk and meat are still an important part of the diet in some areas of Arctic Canada and Greenland.
Share of catch
Historically, the catch of narwhals or other large animals was divided and shared among participating hunters and their extended families according to complex traditional rules (Inuktitut ningiqtuq, Greenlandic ningerpoq). This helped to ensure that the entire camp or community received a portion of the catch (Wenzel 1995). More recently, the regulation of narwhal hunting and changing hunting methods and equipment have led to changes in the sharing system (Sejersen 2001). In Greenland particularly, part of the catch is sold in the open-air markets (Greenlandic Kalaalimineerniarfik, Danish brædtet) present in every village and town. This provides a welcome source of income for hunters and a way for non-hunters to access wild country foods.
Hunting occurs during the open water season from boats and from the floe edge during the fall, winter and spring. The timing of the hunt depends on the weather, the nature of the ice, and the movements of the narwhals. The timing of each of these depends on location. For example, Arctic Bay generally has a shorter hunting period (June–September) than Pangnirtung, which may run from March to November (Heide-Jørgensen et al. 2013b).
In West Greenland, in the Upernavik, Uummanaaq and Disko Bay areas, hunting generally occurs during the fall and winter (NAMMCO 2013). In the far north of West Greenland, hunters from Qaanaaq sometimes see narwhals in the Smith Sound area in winter and spring (January–June). However, most hunting takes place between May and September, with peaks in the months of July and August (Heide-Jørgensen et al. 2013b).
In East Greenland, the majority of the harvest occurs during the summer months (Heide-Jørgensen and Laidre 2009). As with other stocks, the timing of the hunt depends on the movement of the narwhals.
The following descriptions of hunting methods in Canada and Greenland were taken from the NAMMCO Expert Group Meeting to Assess the Hunting Methods for Small Cetaceans, held in 2011 (NAMMCO, 2012):
In West Greenland and Canada, narwhals are hunted during the spring, summer and fall from small boats, or at the ice edge or at ice cracks. The kayak is still used for hunting in some areas of West Greenland. In this type of hunting, the animal is approached quietly by one or two kayaks and the hunter uses a hand-held harpoon with a detachable head (Greenlandic: tuukaak). The harpoon head is attached by a line to a float (Greenlandic: quataq), which is then used to a drag or brake (Greenlandic: miutak) so as to slow the wounded animal. The hunter then shoots the whale with a high-powered rifle when it resurfaces. Having the float attached before shooting minimises the risk that the animal is struck but lost by the hunter.
Similar hunting methods are used from small motor boats and from the ice in Greenland and Canada. Ideally, the whale is harpooned first to secure it; it is thereafter dispatched using a rifle. The harpoon strike alone is, in some cases, sufficient to kill the animal. In other cases, the narwhal is shot first to wound it and slow it down so it can be secured using a harpoon and line.
Nets are sometimes used to capture narwhals in the far north of Greenland, particularly during the dark season and in very heavy ice. The narwhal swims into the net, becomes entangled, and will drown if it cannot surface. If they remain alive, they are shot by the hunter when the net is checked.
REPORTED CATCHES IN NAMMCO MEMBER COUNTRIES
|Greenland||2020||Zone 1 - Etah||2||6|
|Greenland||2020||Zone 2 - Qaanaaq||91||93|
|Greenland||2020||Zone 3 - Melville Bugt||46||71|
|Greenland||2020||Zone 4 - Uummannaq||16||197|
|Greenland||2020||Zone 5 - Disko bugt||68||153|
|Greenland||2020||Zone 6 - Tasiilaq||22||12|
|Greenland||2020||Zone 7 - Ittoqqortoormiit||36||32|
|Greenland||2020||Zone 8 - kangerlussuaq||0||0|
|Greenland||2020||Zone 9 - Northeast Greenland||0||0|
|Greenland||1992||Total||*No reported catches||No quota|
This database of reported catches is searchable, meaning you can filter the information by for instance 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.
DIRECT AND INDIRECT IMPACTS OF CLIMATE CHANGE
Narwhals are endemic to the Arctic and depend on cold water. Their habitat range is therefore being restricted by the warming oceans as a result of climate change. Since they primarily get rid of heat through the dorsal ridge and tail fluke, their ability to adapt to these warming temperatures is also limited. While there have recently been several sightings of narwhals in areas north of their traditional range (e.g. Dove Bay), evidence suggests that a combination of hunting and climate change is negatively impacting the long-term viability of populations in Southeast Greenland.
Two major oceanographic changes linked to climate change have recently been observed in coastal areas of Southeast Greenland – a lack of pack ice in summer and increasing sea temperatures (NAMMCO 2019a). This has had cascading effects on the marine ecosystem, as observed through changed fish fauna and the presence of a large number of boreal cetaceans either new to the area or now occurring in surprisingly large numbers (e.g. humpback, fin, killer, and pilot whales as well as white-beaked dolphins).
Another concern relating to changing sea ice cover is that loss of sea ice, particularly during the summer, may increase the access of killer whales to narwhals, thus increasing predation. Access to narwhals by man is also changing with changes in sea ice concentration and extent. In Smith Sound, climate change has decreased spring and summer ice cover, which has enabled people in North Greenland to access the area and increase their catches (Nielsen 2009). The presence of open water is an important influence on the narwhal hunt, with the majority (72%) of the hunt in Nunavut taking place during the summer months (25th July–1st October) (White 2012).
Narwhals have also recently been moving further west in the Canadian Arctic, perhaps due to changes in sea ice cover, and they have been sighted and hunted near communities in the Central Canadian Arctic where they have seldom been seen before (White 2012).
Increasing industrial development in the Arctic, especially increased ship traffic, could also pose a threat to narwhal populations. Narwhals can detect the noise made by large icebreakers from at least 25 to 30 km away (Cosens and Dueck 1993). Other studies have found narwhals reacting to such noise at distances from 40–60 km (Finlay et al. 1990, Cosens and Dueck 1988). Communities close to shipping routes in the NW Passage, Arctic Bay and Pond Inlet, report fewer narwhals in their areas than there have been in the past, and some hunters attribute this to increased ship traffic (White 2012). This is a concern as ship traffic is expected to increase as sea ice cover decreases with climate change.
Prior to 1996, there had been very little fishing in NAFO Division 0A, the waters on the Canadian side of Baffin Bay. Since 1998, the Greenland halibut fishery in this area has expanded. Currently, both otter trawls and gillnets are used in this fishery. As the fishery has expanded, concerns have been raised by both DFO and the Nunavut Wildlife Management Board that narwhals could be affected by removal of their primary prey species on their overwintering grounds, damage to bottom habitat by trawling, and entanglement in lost gillnets.
In order to mitigate these concerns, a number of measures were introduced. For example, an end date of 10th November was established for the gill net season, in an effort to reduce the risk of gear loss due to late season ice conditions. This date may be changed in response to seasonal conditions. Furthermore, starting in 2007, the southeast part of NAFO area 0A was closed to Greenland halibut fishing in order to protect this important food source for overwintering narwhals.
OIL AND GAS EXPLORATION
Better drilling technology and a warming climate have increased interest in northern areas previously inaccessible to oil and gas exploration. It has been estimated that more than 20 million barrels of undiscovered oil and still greater quantities of natural gas might exist on the continental shelf of East and West Greenland, with still more in the Canadian Arctic Archipelago (Gautier et al. 2009). Seismic exploration, which involves the discharge of airguns that create very loud low-frequency sounds underwater, have been conducted off West Greenland since 2007, and is expected to begin soon off East Greenland. Recently, Heide Jørgensen et al. (2013c) reviewed the potential effects of these activities on narwhals and other Arctic marine mammals.
Like all toothed whales, narwhals use their echolocation abilities to find prey, avoid predators and in navigation. Narwhals also use it to find openings in dense pack ice where they can come up to breathe. In addition to echolocation, narwhals have a broad vocal repertoire that they use to stay in touch with other members of their pod. Their Arctic habitat has heretofore been largely unaffected by human-caused sounds, to which they are therefore unaccustomed.
The effects of ship noise, seismic exploration, drilling, and other sounds on narwhals have been largely unstudied, but could include short or long term changes in behaviour, such as feeding activities and vocalization. Noise could also induce avoidance responses and changes in migratory timing and routes. Extremely loud sounds, such as those produced by seismic exploration, have the potential to directly damage narwhal hearing if they occur at close range, in addition to masking environmental sounds that may be important to narwhals. Narwhals have been observed to react to vessel noise even at long distance and low sound intensity, generally by leaving the area and reducing their vocalisations.
Recently, experiments were conducted exposing narwhals (fitted with satellite tags and acoustic-behavioral recorders) to low level noise from airguns. Preliminary results indicate movement towards the surface and a decrease in vocalisations related to foraging, despite the airguns used in the experiment being less powerful than those used in commercial activities and emitting noise at a level within the range of background noise (NAMMCO 2019a).
THE NATURAL RISK OF ENTRAPMENTS MAY BE INCREASED BY SEISMIC ACTIVITIES
Narwhals spend about half the year in their winter feeding areas, in a marine environment covered by dense pack ice. Although narwhals are among the most ice-adapted of whales, they are still subject to occasional entrapments when the ice freezes up or closes around them, leaving them dependent on a small breathing hole and often resulting in their death when the breathing hole closes. The circumstances leading to entrapments are well known to the Inuit inhabitants of Disko Bay in West Greenland, who have historically harvested whales that have become entrapped. However, in recent years, entrapments have occurred in other areas where they have not been frequently observed, leading Heide-Jørgensen et al. (2013c) to speculate that seismic activities in Baffin Bay may have contributed to these events.
In November 2008, over 1,000 narwhals were entrapped in the ice near Pond Inlet, Nunavut, in an area of Lancaster Sound that freezes solid in the winter and is not therefore winter habitat for cetaceans. Previous tagging experiments have demonstrated that most narwhals begin their southward migration from this area by the end of September. However, seismic exploration was occurring in Baffin Bay in September and October of the same year and it is possible that the noise produced by this activity may have delayed or prevented the narwhals from migrating and thereby contributed to the entrapment. All of these animals eventually died, most of them harvested by local Inuit who knew they would not survive the winter.
Smaller entrapments occurred in Inglefield Bredning in Northwest Greenland in November 2009 and February 2010. Again, this is normally summer habitat for narwhals and they are thought to leave the area well before November. Again, seismic activity in Baffin Bay in September and October 2009 may have delayed or prevented their migration from the area.
Further research is needed
While these occurrences do not constitute conclusive proof that seismic activities are affecting the timing of narwhal migrations, they certainly demonstrate the need for caution in pursuing these activities in or close to narwhal habitat. Heide-Jørgensen et al. (2013c) conclude that further research on the effects of anthropogenic noise on narwhals and other Arctic marine mammals is urgently needed and that this research should ideally precede any further such activities in the area.
Watch a video of narwhals swimming into ice and becoming temporarily entrapped
Research on narwhal and other marine mammals is carried out through the Greenland Institute of Natural Resources (GINR) in Nuuk, Greenland. Research carried out in both East and West Greenland has included the collection and analysis of samples for genetic studies, the application of satellite tags, and abundance surveys.
Abundance surveys provide important information on the size of the population and the trends over time. The last aerial surveys for narwhals in Greenland were carried out in 2019 in Inglefield Bredning and Melville Bay in Northwest Greenland. Aerial surveys for narwhals in East Greenland are planned for the area around Ittoqqortoormitt in the spring of 2020.
Genetic studies are used to try to determine stock structure and relationships, while satellite tagging provides information on stock structure through narwhal movements and habitat use. Another use of satellite tags is to record ocean temperatures and depths and tags on narwhals have been used for this (see Laidre et al., 2010). Satellite-tagging studies of narwhals in both Canada and Greenland were initiated in 1993 and have been ongoing since then (Heide-Jørgensen et al., 2013b). Satellite telemetry of narwhals in East Greenland started in 2010, continued through 2019 and will become an increased focus in 2020 (National Progress Report Greenland 2019). Telemetry studies of narwhals in Scoresbysund, East Greenland, started in 2020 and tagging of animals in this area is planned to continue (National Progress Report Greenland 2019).
Work has also been done in Greenland on ageing methods for narwhals. A new species-specific racemization rate for narwhals has been estimated by regressing aspartic acid D/L ratios in eye lens nuclei against growth layer groups (GLG) in tusks (NAMMCO, 2013; Garde et al., 2007). This information is used to better estimate the age of a narwhal and to then understand age distribution and estimate life history parameters for stocks.
GINR has also been conducting a large-scale project on narwhal ecology and biology in Scoresby Sound, East Greenland. Read more about GINR’s work here.
In 2019, the Greenland Climate Research Centre began a pilot study to monitor narwhals and glacier fronts with automated cameras (National Progress Report Greenland 2019).
In East Greenland, narwhals are the focus of a series of satellite telemetry studies run by GINR in order to understand the stock delineation and to obtain complementary data for abundance estimates. The Climate Research Centre (GCRC) at GINR is establishing a network of acoustic and oceanographic moorings and a pilot study to monitor narwhals and glacier fronts with automated cameras (National Progress Report Greenland 2018). Surveys are also ongoing in different areas.
In Norway, narwhal research is carried out by the Norwegian Polar Institute. In one study, several narwhals off Svalbard were fitted with satellite tags in order to record their diving depths and duration of those dives (Lydersen et al. 2007). This research is not ongoing at the present time. Acoustic recorders were deployed in the Fram Strait in autumn 2018, with the main objective of listening for bowhead whales, belugas and narwhals (National Progress Report Norway 2018). These devices were serviced and redeployed in 2019 (National Progress Report Norway 2019).
In 2019, biopsies from 6 narwhals were collected in the drifting ice in the Framstrait. The biopsies were taken from a helicopter, using FF Kronprins Haakon as a base ship. These samples will be used for genetic and diet studies (National Progress Report Norway 2019).
Asselin N.C. and Richard P.R. (2011). Results of narwhal (Monodon monoceros) aerial surveys in Admiralty Inlet, August 2010. DFO Canadian Science Advisory Secretariat. Res. Doc. 2011/065: iv + 26 p. http://www.dfo-mpo.gc.ca/csas-sccs/Publications/ResDocs-DocRech/2011/2011_065-eng.html
Asselin, N.C., Ferguson, S.H., Richard, P.R. and Barber, D.G. (2012). Results of narwhal (Monodon monoceros) aerial surveys in northern Hudson Bay, August 2011. DFO Canadian Science Advisory Secretariat. Res. Doc. 2012/037. iii + 23 p. http://www.dfo-mpo.gc.ca/csas-sccs/Publications/ResDocs-DocRech/2012/2012_037-eng.html
Cosens, S.E. and Dueck, L.P. (1988). Responses of migrating narwhal and beluga to icebreaker traffic at the Admiralty Inlet ice-edge, N.W.T. in 1986. In W.M. Sackinger and M.O. Jeffries (eds.), Port and ocean engineering under arctic conditions (Vol. 2, pp. 39-54). Fairbanks: University of Alaska Fairbanks.
Cosens, S.E. and Dueck, L.P. (1993). Icebreaker noise in Lancaster Sound, N.W.T., Canada: Implications for marine mammal behaviour. Marine Mammal Science, 9, 285-300. https://doi.org/10.1111/j.1748-7692.1993.tb00456.x
de March, B.G.E and Stern, G. (2003). Stock separation of narwhal (Monodon monoceros) in Canada based on organochlorine contaminants. DFO Canadian Science Advisory Secretariat. Res. Doc. 2003/079. http://www.dfo-mpo.gc.ca/csas-sccs/publications/resdocs-docrech/2003/2003_079-eng.htm
Department of Fisheries and Oceans Canada (DFO). (2006). Fishery Management Plan Greenland Halibut NAFO Subarea 0, 2006-2008.
Department of Fisheries and Oceans Canada (DFO). (2007). Development of a Closed Area in NAFO 0A to protect Narwhal Over-Wintering Grounds, including Deep-sea Corals. DFO Canadian Science Advisory Secretariat. Sci. Resp. 2007/002. https://waves-vagues.dfo-mpo.gc.ca/Library/329004.pdf
Department of Fisheries and Oceans Canada (DFO). (2008). Total Allowable Harvest recommendations for Nunavut narwhal and beluga populations. DFO Canadian Science Advisory Secretariat. Sci. Advis. Rep. 2008/035. http://www.dfo-mpo.gc.ca/csas-sccs/Publications/SAR-AS/2008/2008_035-eng.htm
Department of Fisheries and Oceans Canada (DFO). (2010). Stock definition of belugas and narwhals in Nunavut. DFO Canadian Science Advisory Secretariat. Sci. Advis. Rep. 2009/079. http://www.dfo-mpo.gc.ca/csas-sccs/Publications/SAR-AS/2009/2009_079-eng.htm
Department of Fisheries and Oceans Canada (DFO). (2012a). Abundance and total allowable landed catch for the Admiralty Inlet narwhal stock in 2010. DFO Canadian Science Advisory Secretariat. Sci. Advis. Rep. 2012/048. http://www.dfo-mpo.gc.ca/csas-sccs/Publications/SAR-AS/2012/2012_048-eng.html
Department of Fisheries and Oceans Canada (DFO). (2012b). Advice on total allowable landed catch for the Baffin Bay narwhal population. DFO Canadian Science Advisory Secretariat. Sci. Advis. Rep. 2012/021. http://www.dfo-mpo.gc.ca/csas-sccs/Publications/SAR-AS/2012/2012_021-eng.html
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