|Scientific Name:||Pagophilus groenlandicus|
|Species Authority:||(Erxleben, 1777)|
Phoca groenlandica Erxleben, 1777
Phoca groenlandica Erxleben, 1777
|Taxonomic Notes:||The scientific name for the Harp Seal has shifted frequently in the past with generic names of Pagophoca, Pagophilis and Phoca, and specific names of groenlandicus and groenlandica. Berta and Churchill (2011) used the name Pagophilis groenlandicus and that is the name recognized by the Society of Marine Mammalogy (Committee on Taxonomy 2014). Rice (1998) recognized two subspecies, P. g. groenlandicus and P. g. oceanicus, the former breeding in the western North Atlantic off North America and also around Jan Mayen in the Greenland Sea, and the latter breeding in the White Sea. There certainly are three distinct populations (Lavigne 2002) centred on the breeding localities, with some associated morphological, genetic and behavioural differences. Heptner et al. (1996) provided evidence for two distinct groups, but included the Jan Mayen breeding group with the White Sea group. Analysis of DNA sequence variation, and also comparisons of fingerprint band-sharing coefficients, revealed that the breeding groups in the Northwest Atlantic (Gulf of St. Lawrence and the Front off Labrador and Newfoundland) were one group and that the animals that breed in the White Sea and those in the Greenland Sea (north of Jan Mayen) were another group (Meisfjord and Sundt 1996, Perry et al. 2000). Given the uncertainties in the level of genetic differentiation between the breeding populations (i.e., whether subspecies should be recognized) and their actual affinities, they will not be differentiated in this assessment.|
|Red List Category & Criteria:||Least Concern ver 3.1|
|Facilitator/Compiler(s):||Lowry, L., Ahonen, H., Pollock, C.M., Chiozza, F. & Battistoni, A.|
Due to its large population size, and the increasing trend in two of three major population groups, the Harp Seal should continue to be classified by IUCN as Least Concern. However, climate change poses a serious threat to this ice-associated species and Harp Seals should be reassessed within a decade. Reductions in pup production and declines in body condition have recently been documented in the Northeast Atlantic breeding groups that are thought to be due to environmental change linked to warmer water and less sea ice.
|Previously published Red List assessments:|
|Range Description:||Harp Seals are widespread in the North Atlantic and the adjacent Arctic Ocean and shelf seas. Their range extends from a western extreme in northern Hudson Bay and the Foxe Basin, Baffin Island and the Davis Strait, eastward through the Gulf of Saint Lawrence and Newfoundland region in the western North Atlantic, along the southwest and south coasts of Greenland, continuing east to Iceland and from there to northern Norway and the White, Barents and Kara Seas. The northern limit in the eastern North Atlantic is at least to Franz Joseph Land and Svalbard; in some years Harp Seals may range northward to between 82° and 85° north, depending on ice conditions (Lavigne and Kovacs 1988, Rice 1998, Lavigne 2002). |
The southern limit of Harp Seal distribution off North America shifts southeast in some years to the Gulf of Maine and Sable Island where large numbers of animals have been recorded at times since the mid-1990s (Lacoste and Stenson 2000, Harris et al. 2002, Lucas and Daoust 2002). Harp Seals often occur as vagrants outside this range, south to Virginia in the United States (Scheffer 1958, Rice 1998). Similarly in Europe, Harp Seals occasionally reach the United Kingdom (Ronald and Healy 1981), the Faroe Islands, Denmark, Germany, France and even Spain (van Bree 1997, Bloch et al. 2000).
Prehistorically, Harp Seals occurred in the Baltic Sea. Genetic drift, interspecific completion and overhunting by humans are all factors that are likely to have contributed to their extinction in that region (Stora and Ericson 2004).
Native:Canada; Greenland; Iceland; Norway; Russian Federation; Svalbard and Jan Mayen
Vagrant:Denmark; Faroe Islands; Finland; France; Germany; Spain; United Kingdom; United States
|FAO Marine Fishing Areas:|
Arctic Sea; Atlantic – eastern central; Atlantic – northeast; Atlantic – western central; Atlantic – northwest
|Range Map:||Click here to open the map viewer and explore range.|
|Population:||The Harp Seal is the most abundant pinniped species in the northern hemisphere. Globally this species numbers close to nine million animals with an annual pup production for all breeding sites combined of approximately 1.2 million (ICES 2013, Hammill et al. 2014). The Northwest Atlantic stock is estimated to number close to 7.5 million (Hammill et al. 2014). This stock is thought to be relatively stable, showing little change between the 2004 and 2012 surveys, although pup production has become highly variable with extremely high pup mortality in some recent years. This is a marked recovery from an estimated low of around 1.8 million in the early 1970s, which was a result of overharvesting (Sergeant 1976). Over the period of recovery, catch levels have been increased such that they likely approached potential biological removal levels by the late 1990s (see Johnston et al. 2000). The current quota of 400,000 is likely not sustainable, but this is not a concern because the combined Greenlandic and Canadian harvest average only about half of this number. |
The breeding group in the West Ice near Jan Mayen (often referred to as the Greenland Sea population) was estimated to be 296,000 in 1994; this population increased to approximately 348,000 by 2003 and in 2013 was estimated to be 627,000 (ICES 2013, Øigård et al. 2014). The quota is approximately 20,000 animals, but an average take in the hunt in recent years is about 6,000 (ICES 2013).
The White Sea breeding group was estimated to be 1.8 million animals when surveyed in 2000 (Potelov et al. 2003). An estimate produced in 2013 using data from several pup counts done between 1998 and 2010 suggested that the population had dropped to 1.4 million, most likely due to reduced pup production (ICES 2013). Hunting in recent years in the White Sea has been extremely limited (annual takes of zero to 200 animals); harvesting of pups less than one year of age was banned in Russia in 2009. Norwegian harvests of this population during summer when they are in the Barents Sea have also been very small in recent years, with no hunt at all in 2013 (ICES 2013).
A new Harp Seal whelping patch was found near South Greenland in 2007 (Rosing-Asvid 2008). The source of these animals and the inter-annual stability of this group are not known. This finding was particularly interesting in light of the fact that the Greenlandic harvest of this species has increased from about 1,500 per year in the 1970s up to approximately 100,000 in the year 2000, and has remained at an average of around 85,000 since then (DFO 2012).
|Current Population Trend:||Increasing|
|Habitat and Ecology:||Harp Seals are medium-sized phocids. Adult males and females are similar in size, about 1.8 m long and weighing about 130 kg. Females reach sexual maturity between four and eight years of age (e.g., Frie et al. 2003), and this has varied considerably over the last century, in part as a consequence of population size that has been largely determined by harvest levels and food availability. Males probably do not participate in breeding until they are somewhat older, though they reach physiological maturity around the same time as females. |
Birthing takes place in vast herds from late February to April. There is some variation across the range in the precise timing but herds are highly synchronized (Lavigne and Kovacs 1988). Pups are born on the open, free-floating, pack ice and nursed for 12 days, during which time they gain weight at about 2.2 kg per day (Kovacs and Lavigne 1985, Kovacs 1987, Kovacs et al. 1991, Lydersen and Kovacs 1996). To minimize energy expenditure, most pups are sedentary for the first month; some are so immobile that they melt into the ice beneath them, forming ice “cradles” (Kovacs 1987). Pups are referred to as “whitecoats” because they are born with an insulating coat of white lanugo. Lactating females spend up to 85% of their time in the water, depending on the weather (Lydersen and Kovacs 1993). Towards the end of lactation, females come into oestrus and mate (Lavigne and Kovacs 1988). Weaned pups remain on the ice for up to six weeks, losing up to 50% of their weight before entering the water to feed. During this post-weaning fast they complete moulting of the lanugo. After this coat is shed, the black and silver-gray pelage is exposed and the juveniles are known as “beaters” until they are about a year old.
Gestation lasts about 11.5 months, including a three to four month period of delayed implantation (Stewart et al. 1989). The maximum life span of a Harp Seal is approximately 30 years; most animals that reach sexual maturity live to over 20 years. Both males and females are sexually active until the ends of their lives, showing no reproductive senescence (Ronald and Healey 1981).
Harp Seals older than pups undergo a moult in the post-breeding months, from early April to early May (Lavigne and Kovacs 1988). Harp Seals are highly migratory, and after breeding Canadian Seals follow the pack ice up the coast of Labrador, with small numbers going into Hudson Bay and around Baffin Island, and the rest travelling up both sides of Davis Strait. The Jan Mayen and White Sea groups migrate northward and mix in the Barents Sea (Folkow et al. 2004). The Canadian Seals also spend the summer months in the Arctic; their round-trip migration is over 5,000 km long (Lavigne and Kovacs 1988). They begin the return trip to their breeding grounds (either the Gulf or the Front) in late autumn.
Harp Seals consume a wide range of prey that varies along their migration routes. Their recorded diet includes 67 species of fish and 70 species of invertebrates (Lavigne 2002). Pups and juveniles take a lot of invertebrate prey, especially Euphausiids (Thyanoessa spp.) and pelagic Amphipods (Parathemisto spp.; Haug et al. 2000, Nilssen et al. 2001). Adults in Greenland eat pelagic crustaceans, and fish such as Capelin (Mallotus villosus), Sandeel (Ammodytes sp.), Polar Cod (Boreogadus saida) and Arctic Cod (Arctogadus glacialis). Commercial species such as Atlantic Cod (Gadus morhua) appear to be of minor importance in the diet (Kapel 2000), largely because Harp Seals of all ages eat relatively small prey and tend to specialize somewhat on polar species such as Polar Cod and Capelin (Lindstrom et al. 2013). In the Barents Sea, Harp Seals eat Amphipods, Shrimps and small fish including Polar Cod, Sculpin (Cottidae), Snailfish (Liparidae) and Capelin (Nilssen et al. 1995); but they show a clear preference for large Polar Cod (Wathne et al. 2000, Lindstrom et al. 2013). The Seals off Newfoundland eat Capelin and Arctic Cod, and off Labrador they eat Arctic Cod and Atlantic Herring (Clupea harengus). In the Gulf of St Lawrence, the Seals consume Capelin, Herring, Atlantic Cod, Arctic Cod and Redfish (Sebastes sp.; Lawson et al. 1995). Harp Seals feed heavily in winter and summer and less in spring and autumn. They are a highly social species that travels and forages in groups, yet they maintain a stratification of diet according to age class and depth of the feeding dives.
Harp Seals are relatively shallow divers. Animals satellite-tagged at Jan Mayen stayed close to the edge of the pack ice during the spring moult, usually diving to less than 100 m, but by July tagged Seals in the Barents Sea dove to 400 m. Overall, the deepest dives occurred during the day in winter (Folkow et al. 2004).
Natural predators of Harp Seals include Polar Bears, Killer Whales and Greenland Sharks (Lavigne and Kovacs 1988). In Svalbard, 13% of Polar Bear prey is comprised of Harp Seals (Derocher et al. 2002).
|Continuing decline in area, extent and/or quality of habitat:||Yes|
|Generation Length (years):||15.7|
|Movement patterns:||Not a Migrant|
|Congregatory:||Congregatory (and dispersive)|
|Use and Trade:||
Harp Seals have been harvested for thousands of years by indigenous peoples of the Atlantic Arctic, including coastal Northern Europeans (Lavigne and Kovacs 1988). Basques whalers began taking Harp Seals in the 1500s. By the mid-1600s, French settlers developed land-based netting techniques on the St. Lawrence River. French-Canadians exported 500 tons of oil per year by the mid-1700s, obtained from an estimated take of 6,000 Harp Seals per year. In Newfoundland, English settlers hunted Harp Seals on a larger scale that accounted for an estimated average take of 7,000-12,800 Seals per year for most of the 1700s. By the 1800s, schooner-based sealing developed and the number of Seals harvested rose dramatically; from 1803-1816 the average annual take was 117,000. The peak of sealing in the Northwest Atlantic occurred between 1818 and 1862, when 500,000 Seals were harvested in many years, with maximum yearly takes between 640,000 and 740,000. During that time, it is estimated that 18.3 million Harp Seals, mostly whitecoats, were killed for oil. The records show somewhat lower figures for the Northeast Atlantic. At Jan Mayen, the catch began falling in the late 1850s; the drop in catch was likely attributable to over-harvesting. From 1860 to 1900, an estimated 12.8 million Seals were harvested from the West Ice.
During the 20th century Harp Seals became more valued for their pelts than their oil. In 1917, 143,000 Seals were taken. The catch dropped for a time, then escalated in the 1950s, when it averaged 312,000 Seals per year. In 1960, Canada became concerned about the large numbers of adults being killed, so it placed limits on the length of the hunting season. During the 1960s, an average of 284,000 Seals were taken per year from the Northwest Atlantic stock. In the mid 1960s, adult females became protected on the breeding grounds, and Norway was excluded from sealing in Canadian waters. In 1971 a quota management program was established; from 1970 to 1987 quotas varied from 127,000 per year to 245,000 per year, but the actual harvest was often much lower than the quota (Lavigne and Kovacs 1988). In 1983, the European Economic Community imposed an import ban on all whitecoat products and the average annual harvest in Canadian waters fell to 52,000 Seals from 1983-1995. By 1987, Canada banned the killing of whitecoats and the focus of the hunt switched to beaters (post-weaning to 13 months of age; DFO 2006a). From 1999-2003, the estimated annual mortality of Harp Seals in the Northwest Atlantic was 453,962, broken down into an average of 232,915 taken in the commercial harvest by Canada, 83,000 taken from 1999-2002 in Greenland, and approximately 5,000 taken in the Canadian High Arctic, plus a by-catch of close to 20,000 in the Newfoundland Lumpfish fishery, plus an average annual struck and loss rate of 119,430 from all harvests (Waring et al. 2005).
The Canadian harvest increased with the combined three-year quota (“Total Allowable Catch”) introduced for the period 2003-2005 set at 975,000 (DFO 2005). Given the age structure of the current hunt, this quota would not be sustainable (see Johnston et al. 2000). The current quota is 400,000, but the number taken in the hunt is much less (see above). In addition to Canada’s commercial harvest, some Harp Seals are taken in subsistence hunts in Labrador, Newfoundland, northern Quebec and in Nunavut, as well as in Greenland. In Canada, aboriginal peoples and non-aboriginal coastal residents who reside north of latitude 53 degrees can hunt Seals for subsistence purposes without a permit (DFO 2006b).
In the Northeast Atlantic, Norway established a commercial hunt in 1846, which peaked in the 1870s-1880s when annual catches ranged from 50,000 to 120,000 animals. In the 20th century, annual harvests increased to an average of more than 100,000 per year, with the maximum in the 1920s and 1930s when the catches were 200,000-300,000 per year. In 1989, Norway banned the killing of whitecoats (N-RFC 2005) and harvests in the last few decades have been small compared to historical numbers. Russia also banned the killing of white-coats in 2009 and the White Sea hunt has been almost negligible since that time.
The numbers of Harp Seals struck-and-lost in the both the current commercial hunts (which focus largely on one plus animals) and in subsistence hunting is high, and most harvest estimates do not account for this additional mortality (see Lavigne 1999). The struck and loss rate for Harp Seals in Greenland could be as high as 50% (Sjare and Stenson 2002).
As noted earlier, Harp Seals have been harvested for thousands of years but currently the population is large and the number of animals harvested is declining.
Reduced availability of potential prey, especially Polar Cod, Capelin and Herring, is a threat to Harp Seals. Several Harp Seal “invasions” took place in recent decades along the north coast of Norway. By-catch mortality in nets during those events was estimated to be as high as 100,000 animals in 1987 and 21,474 in 1988 (Haug et al. 1991). The reason for these emigrations out of their normal range within the Barents and Greenland Seas seems to have been a collapse of Herring and Capelin stocks due to a combination of overfishing and shifting oceanographic conditions (low temperatures and salinity, and extensive ice cover; Haug et al. 1991, Woodley and Lavigne 1991). More recently, declining Krill abundance has been correlated with declines in both pup production and body condition of Harp Seals in the Barents Sea region, which are likely related to reductions in sea ice in this area (Øigård et al. 2013).
A small tourist industry that visits the whelping patches in the Gulf of St. Lawrence is not thought to pose any risk to the Seals; it uses a rotational mode of operation such that individual Seals are not visited repeatedly (Kovacs and Innes 1990).
Oil spills in the Northwest Atlantic off the east coast of Canada remain a threat to Seals. There is a concern about the impacts of tanker traffic, particularly in places like Lancaster Sound in the eastern Canadian Arctic, which is an important Harp Seal summering area (Reijinders et al. 1993). The discharge from a ruptured tank on the shore of New Brunswick, Canada in March–April 1969 led to 10,000 to 15,000 Seals being heavily coated with oil. The high number of dead pups washing ashore after this event was evidence of the lethal effects of the oil (St. Aubin 1990). Oil development in the Barents Sea is ongoing and poses a future threat to Harp Seals in the White Sea and West Ice stocks.
Harp Seals have been found to carry significant loads of contaminants including metals, DDT and PCBs (Ronald et al. 1984ab). Organochlorines are still present in their blood, despite DDT levels in the environment (and PCBs to a lesser extent) declining from the early 1970s to the 1980s (Addison et al. 1984) and further in the 1990s and 2000s (Muir and de Wit 2010).
Phocine distemper virus (PDV) was first found in Harp Seals from the West Ice off Jan Mayen in 1987 and 1989. It is widespread in Harp Seals, but only shows up as antibodies; it is not known if there are significant health effects or mortality from PDV infection in this species (Daoust et al. 1993, Duignan et al. 1997). Harp Seals might have been the carriers responsible for the Harbour Seal PDV epidemic in Europe in 1988 (Markussen and Have 1992). PDV also appeared Harp Seals in the Gulf of St. Lawrence in 1991, but not in epidemic proportions (Daoust et al. 1993).
Global climate warming is of notable concern for this species. There have already been major reductions in the extent and seasonal duration of sea ice cover in the Northern Hemisphere, creating a threat to many species of ice-associated marine mammals (Tynan and DeMaster 1997, Learmonth et al. 2006, Kovacs and Lydersen 2008, Laidre et al. 2008, Laidre et al. 2015). Pinnipeds such as the Harp Seal that are dependent on sea ice for pupping, moulting and resting are likely to be heavily impacted by future changes in their sea ice habitats (Johnston et al. 2005, Friedlaender et al. 2007, Kovacs et al. 2011, Kovacs et al. 2012). The high variability in pup production numbers in Canada, as well as the condition declines in the Northeast Atlantic, are thought to be linked to changing oceanographic and sea ice conditions. The degree of plasticity Harp Seals might show with respect to temporal or spatial shifts in breeding times and areas is not known.
Canada has in place sealing regulations pursuant to the 1993 Marine Mammal Regulations that require annual quotas, referred to as “Total Allowable Catches” hunting licenses, and official observers of the commercial Harp Seal hunt (DFO 2005). In the northeast Atlantic, quotas for sealing are based on recommendations made by the International Council for Exploration of the Sea (ICES) and the Northwest Atlantic Fisheries Organisation (NAFO). Russia is responsible for managing Harp Seals in the southeast part of the Barents Sea, while Norway is responsible for managing stocks in the Greenland Sea near Jan Mayen (N-RFC 2005, NMFCA 2006). However, these harvest control mechanisms are no longer particularly influential given the declining interest in Seal harvesting by commercial operators.
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|Citation:||Kovacs, K.M. 2015. Pagophilus groenlandicus. The IUCN Red List of Threatened Species 2015: e.T41671A45231087.Downloaded on 31 August 2016.|