Ringed Seal

Updated: August 2016

The ringed seal is the smallest of all living seal species, with males reaching a length of 1.5 m and a weight of 95 kg, and females 1.4 m and 80 kg (Bonner 1994). The ringed seal has a north circumpolar distribution. It is the most ice-adapted of seals, and is known to occur throughout the Arctic Ocean, including the north pole (Reeves 1998). The name of the ringed seal refers to the light-coloured rings on the dark grey pelt that are visible on adult animals.

The NAMMCO Scientific Committee reviewed the status of the ringed seal in 1996 (NAMMCO 1997) and initiated the compilation of papers and studies reflecting the present knowledge on the species, which formed the first volume in the NAMMCO Scientific Publications series, Ringed seals in the North Atlantic, edited by Mads Peter Heide-Jørgensen and Christian Lydersen. This review takes this monograph as a starting point, reviewing mainly the knowledge which have emanated since, using in particular three recent reviews (Kovacs et al. 2008, Kelly et al. 2010b, Kovacs 2014) and focussing on the work done in the NAMMCO area.

Ringed seal assessment table

ABUNDANCE

Around 5 million (extrapolated from density of ringed seals in various ice types)

DISTRIBUTION

Circumpolar distribution throughout the Arctic, including the North Pole, and Subarctic, also ranging widely into adjacent seas.

RELATION TO HUMANS

Hunted by native peoples for food and leather in Alaska, Canada, Greenland and Russia. Limited sport hunting off northern Norway.

CONSERVATION AND MANAGEMENT

National (and regional) management. Hunting licence required in Canada, Greenland and Russia, but no restriction on season or numbers that can be taken.

Hunting closed in Svalbard during breeding season and quota system for sport hunters off northern Norway.

At present little evidence of depletion, but the species is/will be challenged by the impact of climate change with predicted reduction in distribution range and numbers.

© T. Haug/IMR

© NOAA

© NOAA

Latin: Pusa/Phoca hispida (Schreber, 1775)

Faroese: Ringkópur
Greenlandic: Natseq
Icelandic: Hringanórir
Norwegian: Ringsel
English: Ringed seal, fjord seal, jar seal
French: Phoque annelé, phoque marbré
Spanish: Foca ocelada
Danish: Ringsæl

LIFESPAN

Up to 45 years (Lydersen 1998)

AVERAGE SIZE

Adult individuals reach between 1.10 and 1.60 m in length and weigh between 50 and 110 kg in winter when they are fattest (Rosing-Asvid 2010), males being somewhat larger than females (Bonner 1994). There is considerable geographical variation in size within and among areas (Reeves et al. 1992)

MIGRATION AND MOVEMENTS

Ringed seals are completely adapted to ice-covered waters and do not migrate to open water areas in the winter. However, individual seals may relocate over considerable distances (few thousand km) and substantial migrations, either north-south or inshore-offshore, have been suggested (e.g., Reeves 1998)

FEEDING

Ringed seals are opportunistic feeders, preying on a wide variety of fish, crustaceans and cephalopods, with polar cod being a common prey species of adults, while younger seals feed heavily on amphipods and euphausiids. There are important regional and seasonal differences in diet, reflecting habitat-specific prey availability (Kelly et al. 2010b, Kovacs 2014)

© T. Jacobsen, Polarimages.dk

GENERAL CHARACTERISTICS

The ringed seal is the smallest of all living seal species. It is the most common seal of the Arctic and the most strongly ice-adapted/ associated. Ringed seals are divided into five subspecies on the basis of geographical isolation: Phoca hispida hispida of the Arctic Ocean (the Arctic ringed seal), P. hispida ochotensis of the Sea of Okhotsk and northern Japan, P. hispida botnica of the Baltic Sea and two living in fresh water lakes, P. hispida ladogensis of Lake Ladoga in Russia, and P. hispida saimensis of Lake Saimaa in Finland. The subspecies Phoca hispida hispida, the Arctic ringed seal, which inhabits all of the circumpolar Arctic Ocean, is the only subspecies present in the NAMMCO area.

Note the sharp foreclaws © Fernando Ugarte

Note the sharp foreclaws © Fernando Ugarte

The ringed seal belongs to the family of true seals, also called phocids, and earless or hair seals. The name of the ringed seal refers to the light-coloured rings on the dark grey pelt that are visible on adult animals and prominent on the back and sides. The pup begins shedding its fine, woolly and white lanugo (the hair of fetal and newborn seals) at about 2 months of age when it is replace by a largely un-spotted coat, silver on the belly and dark grey on the back, the same colour as the adults. Animals with this coat are called silver-jars, they acquire rings on their pelage gradually with age.

The ringed seal body is fusiform in shape. In winter, when seals are the fattest, the girth can exceed 80% of the body length (Reeves et al. 1992). The muzzle is short and the head cat-like. Males are slightly larger than females, and in the spring male’s faces appear to be much darker than those of females because of an oily secretion from glands in the facial region. At other times of the year the sexes are difficult to distinguish.

The adults have strong, sharp foreclaws, which are used to maintain breathing holes in the fast ice. Pups are born with the full complement of permanent adult teeth.

Listen to ringed seals here and here

LIFE HISTORY AND ECOLOGY

Survival rates are not well known, but ringed seals are relatively long-lived and can live in excess of 40 years (McLaren 1958, Lydersen 1998). Their average life span is about 15‐28 years (Kelly et al. 2010b).

Female ringed seals begin to reach sexual maturity at age 3 to 5, but the timing is variable and some may not mature until they are 7 to 8 years old, with geographic and temporal variability depending on animal condition and population structure (e.g., Reeves 1998, Sipilä and Hyvärinen 1998, Krafft et al. 2006b, Kovacs et al. 2008, Kelly et al. 2010b, Kovacs 2014). The mean age at sexual maturity of females has decreased significantly in several areas compared to earlier periods (Krafft et al. 2006b, Kovacs 2014, see also under ‘Current abundance and Trends‘). Thereafter ringed seal females usually produce a single pup each year, although this may decline if conditions are not favourable (eg. Kingsley and Byers 1998, Kovacs et al. 2008, Kelly et al. 2010). Reproductive success depends on many factors including prey availability, the relative stability of ice, and sufficient snow accumulation prior to the commencement of breeding so that the birth lair can be constructed (Kovacs et al. 2008).

Males mature about 2 years later than females at 5-7 years (e.g. Krafft et al. 2006b, Kelly et al. 2010b) and likely do not participate in breeding before they are between 8 and 10 years old (Kovacs et al. 2008).

MOULTING

Timing-reproduction-life cycle- Kelly et al 2010

Approximate annual timing of reproduction and moulting for Arctic ringed seals (from Kelly et al. 2010b). Yellow bars indicate the “normal” range over which each event is reported to occur and orange bars indicate the “peak” timing of each event.

Ringed seals can begin to moult as early as late April, with the number of moulting seals increasing in May and peaking in June. The seals spend a lot of time (up to 60%) hauled out on ice basking in the sun both just before and during moulting, a behavior attributed to the need to maintain an elevated skin temperature (Kelly et al. 2010ab). Feeding activity is at a minimum during the spring moult and ringed seals lose a lot of weight and are therefore thin in the summer (Ryg et al. 1990, Rosing-Asvid 2010). Consequently they sink more easily when hunted in the early summer. In August-September, they begin to put on weight again and by December they have returned at their maximum weight.

HABITAT AND MOVEMENTS

Ringed seals occur in areas of landfast and drifting pack ice over virtually any water depth. While they may prefer areas of landfast ice for breeding, they may also breed successfully in areas of stable pack ice, such as Baffin Bay and the Greenland Sea. Unlike other northern seals such as harp and hooded seals, the ringed seal is completely adapted to ice-covered waters and does not migrate to open water areas in the winter (Reeves 1998).

Instead ringed seals are able to maintain several breathing holes in ice that may be over 2 m in thickness, using their strong sharp foreclaws and teeth to scratch through the ice. This allows them to thrive in areas where even other ice-associated seals cannot reside. During the summer ringed seals forage in areas of pack ice or open water, and may haul out on land where no ice is available.

In the summer and fall, when land-fast ice is not available, ringed seals show considerable diversity in their distribution patterns (Kovacs 2014). Some animals remain in the general vicinity of their breeding sites while others disperse along coastlines, concentrating their time near glacier fronts, some spend time in open water far from the coast, and yet others move north to the southern edge of the permanent ice (e.g. Teilmann et al. 1999, Gjertz et al. 2000, Born et al. 2002, Freitas et al. 2008a). Ringed seals are more mobile and have larger ‘home ranges’ during the open-water season than at other times of the year (e.g., Born et al. 2004).

During the fast-ice seasons, each ringed seal uses several haul-out lairs and additional breathing holes within its home range and travels between them quite regularly. A seal’s lairs are usually only a few hundred meters apart, male’s lairs being spread over greater distances on average than those of females. During the reproductive season females spend more time on average out of the water than males and both sexes shift from hauling out during the night in early spring to hauling out during day-time hours in late spring, with more time spent on the surface during the latter period (Kelly and Quakenbush 1990, Carlens et al. 2006).

It is still unclear whether ringed seals show fidelity to natal sites, or are faithful to breeding sites as adults. This may depend on the quality of the sites (predictable ice stability, sufficient snow to construct lairs, good food availability), and there could be regional and subspecies differences in site fidelity. Ringed seals show a high degree of spatial fidelity (territoriality) in the Baltic (Härkönen et al. 2008). Prime habitat for ringed seals may be used over long periods of time, but there are also reports that strongly suggest that there is considerable mobility among ringed seals in some areas (Kovacs 2014).

Ringed seals can travel significant distances, well over 1000 km (e.g., Kapel et al. 1998, Ridoux et al. 1998). However, satellite tracking studies show that individuals tagged at any one location display variable dispersal patterns, some individuals remaining local throughout the open-water season, while others move offshore or northward to the permanent pack-ice (e.g., Teilmann et al. 1999, Gjertz et al. 2000, Born et al. 2004).

The seasonality of ice cover strongly influences ringed seal movements, as well as foraging, reproductive behavior, and vulnerability to predation (Kelly et al. 2010b).

Feeding

The diet of ringed seals has been well documented across the species’ range, especially in the marine environment (most recently Belikov and Boltunov 1998, Lyersen 1998, Siegstad et al. 1998; Wathne et al. 2000, Holst et al. 2001, Andersen et al. 2004, Carlsen et al. 2006, Stenman and Pöyhönen 2005, Dehn et al. 2007, Agafonova et al. 2007, Labansen et al. 2007, 2011, Vincent-Chambellant 2010, and Kelly et al. 2010b and Kovacs 2014 for review).

Ringed seals are opportunistic feeders and prey on a wide variety of fish and invertebrates, but strong preferences for particular types of prey are evident. Diet is thus determined by the combination of preferences and the regional and seasonal availability of various type of prey. Gadoid fishes dominate the diet at least from late autumn through the spring in many areas, with polar cod (Boreogadus saida) being the most commonly consumed species. This small fish occurs both in ice-free and ice-covered waters, especially at the ice edge, with young polar cod sometimes living in spaces within the sea ice. Other gadoid fish are also seasonally important in some areas, such as Arctic (Arctogadus glacialis) and safron (Eleginus gracilis) cod and navaga (Eleginus nawaga), as well as redfish (Sebastes sp.), capelin (Mallotus villosus), smelt (Osmerus sp.) and herring (Clupea sp.). Invertebrates, both crustaceans and cephalopods, become more important in most areas during the open-water season. Ringed seals around Greenland live mostly in the ice-filled regions of North and East Greenland, where the bulk of the diet is polar cod and parathemisto (a kind of amphipod – see picture).

Fresh Themisto specimen. © Pinngortitaleriffik

Fresh Themisto specimen. © Pinngortitaleriffik

There seem to be age- and sex-related differences in prey composition. Adult ringed seals prefer to feed on pelagic schooling fish in most areas, while younger animals feed heavily on smaller prey such as amphipods and euphausiids. Adult females tend to eat smaller cod than adult males or juveniles.

Most ringed seal prey is small and preferred prey tend to be schooling species that form dense aggregations. Fishes are usually in the 5-10 cm range and crustacean prey in the 2-6 cm range, but larger prey may be taken on occasion. Typically, ringed seals prey upon no more than 10-15 species in any one area, with 2-4 species considered as important prey.

Ringed seals are the only Arctic seal that regularly maintains breathing holes in fast ice. They therefore occupy a vast area of habitat that is impenetrable to other seal species for much of the year. During the open water season and in areas of pack ice, they may occur with other seal species such as walruses (Odobenus rosmarus rosmarus), harp seals (Phoca groenlandica), hooded seals (Cystophora cristata) and bearded seals (Erignathus barbatus), and also whales such as belugas (Delphinapterus leucas), narwhals (Monodon monoceros) and bowhead whales (Balaena mysticetus). The diets of all these species, except for walruses and bearded seals, may overlap with that of ringed seals, and thus competition may be a factor affecting distribution and abundance in some areas.

Predators

Polar bears (Ursus maritimus) are by far the most important predator on ringed seals (e.g., Kelly et al. 2010, Kovacs 2014). Polar bears prey on little else but ringed seals, and commonly kill a seal every 2 to 6 days (Lydersen 1998, Reeves 1998, Rosing-Asvid, 2010; Iversen et al. 2013). They are approximately 26,000 polar bears in the Arctic, which take each year 100s of thousands of ringed seals (e.g., Stirling and Lunn 1997). They kill seals in their subnivean lairs by crashing through the snow roof, or take them at breathing holes. They also stalk seals lying on the ice in the spring and summer, in ice cracks and even in open water. Polar bears tend to be most successful at killing pups and sub-adult seals, but adult seals are also taken.[/caption]

Ringed seals are also preyed upon by walrus (Odobenus rosmarus), killer whales (Orcinus orca), glaucous gulls (Larus hyperboreus) and Greenland sharks (Somniosus microcephalus) (Lydersen 1998, Ridoux et al. 1998, Kelly et al. 2010b, Leclerc et al. 2012, Lydersen and Kovacs 2013). In addition, pups are taken by Arctic (Alopex lagopus) and red (Vulpes vulpes) foxes, wolves (Canis lupus), wolverines (Gulo gulo) ravens (Corvus corax) and dogs in the spring (e.g., Reeves 1998, Kelly et al. 2010b, Kovacs 2014).

Health and Parasites

Although there is limited information on health parameters and disease for ringed seal (Tryland et al. 2006), they have been recently reviewed by Kelly et al. (2010b) and Kovacs (2014). Arctic phocids do not seem to have experienced any of the epizootic events with morbillivirus that have affected seals on the European coast. Many different parasites have been detected in ringed seals (Kelly et al. 2010 and Kovacs 2014 for review), the most commons being helminths in the gastro-intestinal tract. In Svalbard, the abundance of nematodes and acantocephalans in the digestive tract varies with sampling location and seal age and sex, influenced by the fish availability as prey and the age class exploited by the different seal groups (Johansen et al. 2010). Parasite burdens can be quite high in ringed seals, although they seldom debilitate healthy seals.

FUgarte_Disko_050812 066_iii

© Fernando Ugarte

Distribution

Ringed seals occur throughout the Arctic, north to the pole. They are the only northern seal that can maintain breathing holes in thick sea ice (over 2 m in thickness) and this special ability allows them to have an extensive distribution in the Arctic and sub-Arctic and to thrive in areas where even other ice associated seals cannot reside.

In the North Atlantic the ringed seal occurs in marine areas virtually everywhere where there is seasonal ice cover (Reeves 1998, Kelly et al. 2010b, Kovacs 2014). Their global distribution has expanded and contracted with changing sea‐ice cover, and today they inhabit all the seasonally ice‐covered seas of the Northern Hemisphere, as well as some fresh water lakes.

rs-dist-no-borders-webIn the Western Atlantic they occur as far south as northern Newfoundland, northward to the pole and throughout the Canadian Arctic archipelago. They occur throughout Greenland, but are most abundant where fast ice occurs. Ringed seals occur around Svalbard and Franz Josef Land, and are occasionally encountered in the Faroe Islands and off northern Iceland. In the Eastern Atlantic, ringed seals inhabit the entire Eurasian Arctic coast, including the coastal waters of the White Sea and southeastern Barents Sea, the Gulf of Bothnia and the Baltic Sea. Freshwater populations of ringed seals occur in Lake Ladoga in Russia and Lake Saimaa in Finland (Sipilä and Hyvärinen 1998), as well as in Nettilling Lake in Nunavut, Canada.

Extralimital records extend far south on both sides of the Atlantic, to New Jersey in the west and to France and Portugal in the east (Ridoux et al. 1998). A young seal tagged in Brittany in France, was found one year later in a Greenland shark stomach off Iceland, showing that at least some of these, usually young, vagrants may actually have the navigational skills to return to normal habitat (Ridoux et al. 1998).

Habitat and Movements

The ringed seal is the most strongly ice-adapted/associated seal species. Throughout most of its range, it does not come ashore and uses sea ice as a substrate for resting, pupping, and moulting (e.g. Kelly et al. 2010a), coming out of the water exclusively on sea ice except in marginal seas and freshwater lakes where ice disappears seasonally.

Ringed seals occur in areas of landfast and drifting pack ice over virtually any water depth. While they may prefer areas of landfast ice for breeding, they may also breed successfully in areas of stable pack ice, such as Baffin Bay and the Greenland Sea. Unlike other northern seals such as harp and hooded seals, the ringed seal is completely adapted to ice-covered waters and does not migrate to open water areas in the winter (Reeves 1998).

© K.M. Kovacs, Norwegian Polar Institute

© K.M. Kovacs, Norwegian Polar Institute

Instead ringed seals are able to maintain several breathing holes in ice that may be over 2 m in thickness, using their strong sharp foreclaws and teeth to scratch through the ice. This allows them to thrive in areas where even other ice-associated seals cannot reside. During the summer ringed seals forage in areas of pack ice or open water, and may haul out on land where no ice is available.

In the summer and fall, when land-fast ice is not available, ringed seals show considerable diversity in their distribution patterns (Kovacs 2014). Some animals remain in the general vicinity of their breeding sites while others disperse along coastlines, concentrating their time near glacier fronts, some spend time in open water far from the coast, and yet others move north to the southern edge of the permanent ice (e.g., Teilmann et al. 1999, Gjertz et al. 2000, Born et al. 2002, Freitas et al. 2008a). Ringed seals are more mobile and have larger ‘home ranges’ during the open-water season than at other times of the year (e.g., Born et al.2004).

During the fast-ice seasons, each ringed seal uses several haul-out lairs and additional breathing holes within its home range and travels between them quite regularly. A seal’s lairs are usually only a few hundred meters apart, male’s lairs being spread over greater distances on average than those of females. During the reproductive season females spend more time on average out of the water than males and both sexes shift from hauling out during the night in early spring to hauling out during day-time hours in late spring, with more time spent on the surface during the latter period (Kelly and Quakenbush 1990, Carlens et al. 2006).

Whether ringed seals show fidelity to natal sites, or are faithful to breeding sites as adults, and whether this depends on the quality of the sites (predictable ice stability, sufficient snow to construct lairs, good food availability) or whether there are regional and subspecies differences is still unclear. Ringed seals show a high degree of spatial fidelity (territoriality) in the Baltic (Härkönen et al. 2008). Prime habitat for ringed seals may be used over long periods of time, but there are also reports that strongly suggest that there is considerable mobility among ringed seals in some areas (Kovacs 2014).

Ringed seals can travel significant distances, well over 1000 km (e.g., Kapel et al.1998, Ridoux et al. 1998). However, satellite tracking studies show that individuals tagged at any one location display variable dispersal patterns, some individuals remaining local throughout the open-water season, while others move offshore or northward to the permanent pack-ice (e.g., Teilmann et al. 1999, Gjertz et al. 2000, Born et al. 2004).

The seasonality of ice cover strongly influences ringed seal movements, as well as foraging, reproductive behavior, and vulnerability to predation (Kelly et al. 2010b).

STOCK AREAS AND SUBSPECIES

There is no definitive genetic or other information to differentiate stocks of Arctic ringed seals. Their distribution is virtually continuous and there are few geographical barriers that would prevent their dispersion. Indeed, individual tagged ringed seals have been shown to move very long distances on occasion (Kapel et al. 1998, Ridoux et al. 1998, Teilmann et al. 1999). Lately seals tagged in Resolute Bay migrate even longer distance long distances: four travelled 2,500 kilometres to southeast Baffin Island, and another covered 3,000 kilometres, swimming to Frobisher Bay via Greenland (Polar Blog, Canadian Geographic, July 2014).

On the basis of geographical isolation, ringed seals are divided into five subspecies : Pusa hispida hispida of the Arctic Ocean (the Arctic ringed seal), P. hispida ochotensis of the Sea of Okhotsk and northern Japan, P. hispida botnica of the Baltic Sea and the two last living in fresh water lakes, P. hispida ladogensis of Lake Ladoga in Russia, P. hispida saimensis of Lake Saimaa in Finland. The latter four subspecies are well supported; genetic structuring within the Arctic subspecies, however, has yet to be thoroughly investigated, and it may prove to be composed of multiple distinct populations (Kelly et al. 2010b). Ringed seal cannot create breathing holes in the thick multi-year ice found in large parts of the Arctic Ocean and in the Canadian Archipelago north of Baffin Island. This type of ice therefore operates as a natural barrier for ringed seals and, since they prefer to stay in the vicinity of ice, long stretches of open waters will also contain few ringed seals; the Arctic ringed seals therefore consist of several populations, between which there is little interchange (Rosing-Asvid 2010).

rs-dist-no-borders-webOn a North Atlantic scale, the NAMMCO Scientific Committee (NAMMCO 1997a) recognised 3 stock areas (see map below), based primarily on the low likelihood of mixing between the areas. While there is presently no genetic or other evidence to support such stock divisions, they are useful in determining the status of North Atlantic ringed seals.

ringed seal management areas

Delimitation of areas of ringed seal distribution as used by NAMMCO (1997a,b) in assessing abundance and exploitation.

Area 1 is centred on Baffin Bay and includes northeastern Canada and West Greenland. It is separated from Area 2, which includes East Greenland and the Greenland Sea east to Svalbard, by the Greenlandic land mass. Area 3 includes the Barents and Kara Seas east to the Severnaya Zemlya, where it was considered that ice conditions and low productivity would limit the movements of ringed seals.

Current Abundance and Trends

Ringed seals are the most abundant high arctic seal and although no accurate global estimate is available, the species is thought to number at least a few million animals (Reeves 1998).

Counting ringed seals

Ringed seals are difficult to count. Other ice breeding seals, such as harp (Phoca groenlandica) and hooded (Cystophora cristata) seals, birth and rear their pups on the surface of the ice. Aerial surveys for these species are conducted to count the pups during breeding season, and pup counts are then converted to total population estimates. Ringed seals give birth in lairs under the snow that are practically invisible from the ice surface. While they commonly haul out on the ice during the moulting period in late spring, it is unlikely that the entire population would be on the ice surface at any given time. Aerial, ground- or ship-based surveys can detect only those seals that are on the ice or at the surface of the water, and this proportion is usually unknown. Therefore, estimates of ringed seal abundance are simply not available for most areas.

Despite these difficulties, aerial surveys of fast-ice areas during the spring have been and are the most widely used method of assessing the abundance of ringed seals, although it is widely recognized that such counts are underestimates (reviewed by Reeves 1998, and more recently e.g. Frost et al. 2004, Moulton et al. 2005, Bengtson et al. 2005, Krafft et al. 2006a). Surveys must be timed to coincide with peak haul-out season and correction factors are still required to account for the number of animals that are not visible at the time of the survey because they are either in the water, or in some cases still in their snow lairs. A variety of methods have been employed to attempt to correct counts to population estimates (Reeves 1998 for review, Bengtson et al. 2005, Kelly et al. 2006, Krafft et al. 2006a) but calibration issues remain (Carlens et al. 2006, Krafft et al. 2006a). Most if not all abundance surveys to date should probably be considered indices of abundance (Kovacs and Lydersen 2006, Kovacs 2014).

A dog sniffing out a ringed seal lair during counts of ringed seals in Alaska. © University of Southeast Alaska

Counts of breathing holes and/or birth lairs using trained dogs have also proven effective in some areas (Hammill and Smith 1990, Lydersen 1998). Some estimates of abundance have been derived by calculating the number of ringed seals required to support the predation of polar bears and humans in the area. The abundance of polar bears is usually more accurately known than the abundance of ringed seals. For example, Kingsley (1998) used a population estimate for polar bears in Baffin Bay, estimates of their food requirements, and the human harvest by Canada and West Greenland to estimate that there must be at least 1.2 million ringed seals in the area to support this level of predation. Kingsley (1990) used a similar approach to calculate that there must be at least 4 million seals in the Canadian Arctic.

The remoteness and dynamic nature of ringed seal sea‐ice habitat, time spent below the surface, along with their broad distribution and seasonal movements makes surveying ringed seals expensive and logistically challenging, and therefore it is difficult to assess their population size and trend (Kelly et al. 2010b).

The NAMMCO Scientific Committee (NAMMCO 1997a) derived a rough estimate of the abundance of ringed seals in NAMMCO Area 1 (Northeastern Canada – Baffin Bay – West Greenland, see ‘Distribution‘) of approximately 1.3 million seals, based on extending existing estimates to areas of similar habitat. This estimate has a large contribution from pack ice areas, where knowledge of ringed seal density is particularly poor. Nevertheless it is similar to the estimate by Kingsley (1998) for roughly the same area.

ABUNDANCE AND TRENDS

Because of the difficulties in deriving estimates of abundance, there is little information on trends in abundance for most areas. Short-term fluctuations in the numbers of young seals produced have been documented (eg. Kingsley and Byers 1998) and are likely related to annual variations in ice conditions. Seasonal reductions in abundance in the vicinity of hunting communities have also been noted (Reeves 1998). The only areas where population reductions that can definitely be related to over-harvesting have been noted are in the Okotsk Sea and the Baltic Sea. Both these areas were subjected to large-scale commercial harvesting in the past. This harvesting has since been reduced (Okotsk Sea) or has ceased (Baltic Sea), and ringed seal populations are now thought to be recovering in these areas (Reeves 1998). Some small lake populations have also been affected by hunting (Sipilä and Hyvärinen 1998).

The table below gives the most recent abundance estimates for ringed seals in different areas, as well as the conservation status in these areas.

Ringed seal abundance table

Stock Status

Ringed seals are the most abundant high arctic seal and although no accurate global estimate is available, the species is thought to number at least a few million animals (Reeves 1998).

ARCTIC RINGED SEALS

Arctic ringed seals do not form large seasonal aggregations, as do some other seal species, and often occupy areas of pack ice that are extremely remote and inaccessible to hunters. These factors decrease their vulnerability to overexploitation. Harvests in Canada, Greenland and Russia have been sustained for hundreds or even thousands of years with little evidence of depletion. On the other hand reliable information on ringed seal numbers is lacking for most areas, so it is not possible to describe trends in the populations.

The NAMMCO Scientific Committee concluded in 1996 that harvests of arctic ringed seals in the Baffin Bay area (Area 1) were likely sustainable, but cautioned that more information was needed on ringed seal distribution and numbers, especially in pack ice areas (NAMMCO 1997). Harvests in other areas of the North Atlantic presently pose no threat to the populations.

However, the persistence of the Arctic ringed seal, and other subspecies, will be challenged by the impacts of climate change which are already apparent in the Arctic (e.g., Meier et al. 2004, Rosing-Asvid 2006, 2010, Kelly et al. 2010, Lydersen et al. 2007, 2010, 2014, Kovacs et al. 2008, 2012, Kovacs 2014). Habitat loss and deterioration caused by decreases in sea-ice and snow cover will for example lead to increases in pup mortality from premature weaning, hypothermia and predation. Other indirect impacts are also expected, including changes in the food web, increased predation and increased disturbance by human activities. See under ‘Other human impacts‘ for more detail.

Ringed seal tagged in Greenland. © A. Rosing-Asvid

It is predicted that, within the foreseeable future, the number of Arctic ringed seals will decline substantially, and they will no longer persist in substantial portion of their range (Kelly et al. 2010). Kovacs (2014) stresses the importance of developing and implementing an Arctic ringed seal monitoring program, given the ecological and subsistence importance of this species in the Arctic.

Both the international programs CAFF (Conservation of Arctic Flora and Fauna) and AMAP (Arctic Monitoring and Assessment Program) under the Arctic Council have specifically requested that all of the Arctic countries launch scientific monitoring pro­grams on ringed seal population structure, trends in abundance, vital rates and age structures because of this species value as an ‘indicator species’ for monitoring global climate change and contaminant patterns. Today only Norway has a national program for ringed seal monitoring.

OKHOTSK, BALTIC, LAGODA AND SAIMAA RINGED SEALS

Commercial harvests in the Sea of Okhotsk and predator‐control harvests in the Baltic Sea, Lake Ladoga, and Lake Saimaa caused dramatic population declines in the past but have since been restricted. Current harvest levels appear to be low and sustainable. Kovacs et al. (2008) and Kelly et al. (2010) provide status reviews for these four subspecies, which are summarized below.

No recent population data are available for the Sea of Okhotsk population and the current population trend is unknown, but thought to be stable. Climate change impacts are likely to have negative consequences, with decreases in sea-ice quality and extent. The range of the population is bounded by land to the North, and the opportunity to contract its range with the ice is limited.

The Baltic Sea population is presently depleted. However, some recovery in this population has been observed in recent years (Härkönen et al. 1998), with a positive population trend in the Gulf of Bothnia, the primary breeding area (Karlsson et al.2007). Climate change is likely to also have an effect on this subspecies, as current sea ice trends in the Baltic and projections for the next 30 years pose a major threat to all southern populations in the Baltic, with only the Gulf of Bothnia likely to retain fairly good winter sea-ice habitat for ringed seals (Meier et al. 2004).

The Lake Ladoga population is depleted and likely decreasing with mortality due by-catch in fishing gear accounting for 10-16% of the population annually (Verevkin et al. 2006), which is clearly unsustainable. Climate change will be likely lead to a decrease ice habitat and increased pup mortality. As it is a landlocked population, Ladoga ringed seal cannot disperse to new habitat.

The Lake Saimaa population is severely depleted and considered as endangered, with less than 300 seals remaining. Population growth rates vary across the different regions of the lake and are positive in some areas and negative in others. The overall population may increase, but seals may no longer be present in some region of the lake (Sipilä 2006). Bycatch is a significant source of mortality (e.g., Sipilä and Kokkonen 2008), which adds to the consequences of reproductive failure in recent years due to poor ice conditions. Continued degradation of ice and snow habitat will likely further threaten the survival of this population.

STATUS ACCORDING TO OTHER INTERNATIONAL ORGANIZATIONS

Ringed seals have no special conservation status under the Convention on International Trade in Endangered Species of Fauna and Flora (CITES)  and are not listed in any appendix.

On the IUCN “Red list”, ringed seal are listed as Least Concern in an assessment made in 2008. However this assessment stipulates that “However, given the risks posed by climate change to all Ringed Seal subspecies, including the Arctic Ringed Seals, this species should be reassessed within a decade” (Kovacs et al. 2008).

WWF not only sees the Greenlandic Inuit hunt of seals, including ringed seals, as an important component of Greenland culture and economy, but considers the Inuit sealing as sustainable and directly supports it. WWF (2013) calls for the EU to address the impacts of their import bans as well as to act in response by informing the European public about the Inuit exemption. It suggests that “with financial support from the EU, the existing certification label be considered expanded to guarantee e.g. sustainability of the hunt, full utilization of catches and animal welfare to meet increasing demands from conscious consumers in the EU as well as worldwide”.

In Canada, ringed seal has been listed as Not at Risk by COSEWIC/COSEPAC in 1989, and has not been reviewed since. Ringed seals are not listed in the Norwegian Redlist. It is listed as Least Concern in the Greenlandic RedList.

Management

Ringed seals inhabit the waters of two NAMMCO member states, Greenland and Norway. Only the Arctic ringed seal is present in these areas.

Humans have hunted ringed seals in the Arctic since the arrival of people to the region and they remain a fundamental subsistence resource for many northern coastal communities today (e.g., ACIA 2005, Hovelsrud et al. 2008, Kovacs et al. 2008, Kelly et al. 2008). Subsistence and commercial harvests of Arctic ringed seals have been large in the past, but there is no evidence that they have contributed to large‐scale population declines. Commercial harvests in the Sea of Okhotsk and predator‐control harvests in the Baltic Sea, Lake Ladoga, and Lake Saimaa caused population declines in the past but have since been restricted (Kelly et al. 2010).

No international governing body regulates the harvest of ringed seals. Advice on sustainable hunting and management of ringed seals is given by the North Atlantic Marine Mammal Commission (NAMMCO).

In most areas there are relatively few restrictions on the hunting of ringed seals. In Canada, Greenland, Norway and Russia, a licence is required, but there are almost no restrictions on season or the number of animals that can be taken (Belikov and Boltunov 1998, Reeves et al. 1998, Teilmann and Kapel 1998). In Alaska, there are no limitations on the subsistence take of ringed seal. TACs or total allowable catches are not set for ringed seals in Canada, but any commercial harvests are regulated by licenses and permits and wastage is specifically prohibited. In Norway, at Svalbard, licensed hunters can shoot ringed seals from 20 May – 20 March. They are protected during their breeding season, as well as throughout the year in Svalbard national parks and nature reserves. Sport hunting of ringed seals is permitted on the Norwegian mainland. Individual hunters must have a licence, and quotas on how many may be taken are set.

The general lack of catch quotas means that there has been no requirement for hunters to register their catch. While records of commercial trade in sealskins exist for some areas, these likely represent a variable and sometimes small proportion of the number of seals that are actually taken. Hence historical catch records for ringed seals are in many cases poor and incomplete. This situation is changing, however. Greenland has been collecting complete harvest statistics for all species since 1992 under the Piniarneq system (Teilmann and Kapel 1998), and harvest studies are a part of some native land claims in Arctic Canada (Reeves et al. 1998).

GREENLAND

There are no national restrictions in Greenland, but permits are used to control the harvest, and hunting of ringed seals is regulated in nature reserves and many municipalities (Goverment of Greenland 2012). Everyone engaged in hunting in Greenland must have a valid hunting license, either a full time license or a leisure license. Being a full time hunter requires that at least 50% of your income comes from hunting. Full time hunters can be licensed to hunt species like baleen whales and polar bears that leisure hunters are not allowed to hunt. Since 2009 only full time hunters qualify to sell sealskins to the tannery Great Greenland A/S (Government of Greenland 2012a). A hunter must submit a yearly catch report to the Ministry of Fisheries, Hunting and Agriculture. This makes it possible to monitor and evaluate the catch levels of the four different species of seals, both at local and national levels.

UTILISATION

Ringed seal skins © Fernando Ugarte


Drying sealskins in Greenland. © Fernando Ugarte

Drying sealskins in Greenland. © Fernando Ugarte

Ringed seals are the “daily bread” of many northern peoples. The Inuit of Greenland and Arctic Canada particularly are heavily dependent on ringed seals for food, and for skins for clothing and for sale. In some areas of the Arctic at least, the widespread and year-round existence of ringed seals made and make indeed human life possible.

Ringed seals, or “natseq”, can be hunted year-round, even during the dark months, and have therefore always been the most reliable source of daily necessities for the lives of northern peoples. Ringed seals have provided a stable supply of meat and blubber for food, heating and lightning, as well as skins for essential commodities such as “kamiks”, skin clothing, tent coverings, bladder floats (“avataqs”) and other equipment essential for the survival and success of Inuit hunting communities. Even the means of transportation to hunting grounds has been facilitated through the use of ringed seal products. Skins from ringed seals and bearded seals (Erignathus barbatus) is used to cover the fragile frames of the kayaks, and was also formerly used to cover the larger “umiaks” that were used for transportation of whole families, while seal meat is still the essential “fuel” for the dogs that pull the sleds (Heide-Jørgensen and Lydersen 1998). The seals also plays an immense role in Greenlandic mythology.

Ringed seals, particularly in North and East Greenland, remain very important as a source of food for both humans and sled dogs (Rosing-Asvid 2010).

A Falling Income

Ringed seals skins also have commercial value, although less today than at some times in the past (Reeves et al. 1998, Teilmann and Kapel 1998, Belikov and Boltunov 1998). The sale of the skins of young ringed seals continues to be an important source of cash income in Arctic Canada and Greenland (Rosing-Asvid 2010), although it has been drastically reduced in the last decades, because of the anti-sealing campaigns and the resulting 1983 and 2009 bans in the EU. Regardless of the sustainability of the Greenlandic seal hunting and the Inuit exemption, allowing Greenlandic sealskin and other products to be sold on the European market, the hunters and the sealskin business in Greenland are marked by the EU bans, although the Inuit exemption render possible to export of sealskins from Greenland to the EU and place them on the market if the skins are certified according to Regulation no 737/2010.

EU SEALSKIN BAN AND THE INUIT EXEMPTION

In 1983, the European Economic Community imposed an import ban on all whitecoat products (Kovacs 2015). The ban, which was initially for 2 years, has been extended since then and was expanded in 2009 to include juvenile (beater) pelts (Hammill et al. 2015).

Exceptions to the ban include products resulting from Inuit/indigenous harvests; products for the sole purpose of sustainable management of marine resources; and products for the personal use of travelers to the EU. As well, the ban does not apply to seal products trans-shipped through the EU to non-EU destinations (DFO 2016b).

In order for seal products to be exempted from the ban and placed on the market in the EU the Inuit or indigenous harvest must meet certain conditions. The hunt must:

  • be traditionally conducted by the community
  • contribute to the community’s subsistence in order to provide food and income and not be primarily conducted for commercial reasons
  • pay due care to animal welfare, while taking account of the community’s way of life and the subsistence purpose of the hunt (EUR-Lex 2016).

Other Human Impacts

Anthropogenic activities which may affect marine mammals generally and ringed seal specifically can be divided into two main categories: habitat degradation and oceanographic change due to climate change. Climate change denotes changes in major weather patterns over a long time-scale, and results from both natural variability and the influence of human activities. Climate change is by far the most serious threat to Arctic biodiversity and exacerbates all other threats (CAFF 2013).

CLIMATE AND OCEANOGRAPHIC CHANGES

A potential long-term and alarming threat to ringed seals is human-induced global warming. Both the observed and the projected effects of a warming global climate are most extreme in northern high‐latitude regions (e.g., ACIA 2005, CAFF 2013). It has become clear that climate change is occurring and that the Arctic has already undergone significant physical environmental change due to global warming (e.g. ACIA 2005, CAFF 2013, Kovacs 2014 for review). There has been a decrease in the extent, duration and area of Arctic sea ice since the 1970s (Johanessen et al. 1995, Jeffries et al. 2013). This has led to a decrease in the condition and survival of polar bears in Western Hudson Bay in Canada (Stirling et al. 1999), probably because of reduced access to their major prey, the ringed seal. The observed and projected changes with significant potential to affect the ringed seal’s range and habitat, both its physical and biological components, are changes in sea ice, snow cover, ocean temperature, ocean pH (acidity), and associated changes in ringed seal predator and prey species.

Ringed seals are the most ice-associated/adapted pinnipeds in the Arctic and are perhaps the most vulnerable of the high-arctic pinnipeds because they are reliant on sea ice as a platform for resting, whelping, nursing, and moulting, and they depend on snow cover to provide protection from cold and predators and successfully rear young. Ice and snow cover are changing and will continue to do so as the climate warms. Numerous authors have studied and/or warned against the possible impact that global warming will have on the ringed seal (e.g. Stirling et al. 1999, Stirling and Smith 2004, Meier et al. 2004, Ferguson et al. 2005, Stirling 2005, Rosing-Asvid 2006, 2010, Learmonth at al. 2006, Lydersen et al. 2007, 2010, 2014, Sipilä et al. 2007, Freitas et al. 2008b, Härkönen 2008, Kovacs and Lydersen 2008, Laidre et al. 2008, Moore and Huntington 2008, Kovacs et al. 2012).

The impacts of climate change on ringed seals and other Arctic species will be both direct and indirect (e.g. ACIA 2005, CAFF 2013) and are reviewed in Kelly et al. (2010b) and Kovacs (2014). The impacts of climate change and the potential resilience of species are complex, but it is necessary to assess them so that suitable conservation actions can be taken (Moore and Huntington 2008).

A reduction in the extent and duration of ice cover would directly reduce the habitat available to ringed seals. It might also lead to poor condition of pups and higher pup mortality due to the early destruction of birth lairs. In the southern Baltic Sea, a series of nearly ice-free winters from 1989-1995 led to very high pup mortalities (Härkönen et al. 1998). Insufficient snow cover to protect pups in lairs in the spring will also likely lead to higher mortality due to increased predation. In warm years, the ringed seal pups are more exposed to predation from polar bears due to a higher density of lairs on the smaller area of available sea ice and the fact that the lairs are weaker because there is less snow. The seals may also experience periods of thaw that can destroy their lairs and expose the pups (Hezel et al. 2012, Rosing-Asvid 2010). Ice is also needed by ringed seals for moulting, resting, and in some populations foraging, but the type of ice and its stability is not as important for the seals outside of the breeding season. Northern ringed seals still exhibit a clear preference for areas with considerable ice coverage (e.g. Freitas et al. 2008).

Beyond the direct changes to their habitat, climate change will pose risks to ringed seals by inducing indirect changes. These will include changes to their forage base (species and density shifts, and distributional shifts of prey species, etc.), increased competition from temperate species, increased predation rates from polar bears and arctic foxes (at least initially) as well as killer whales, increased disease and parasite risks, greater potential for exposure to increased pollution loads and impacts via increased human traffic and development in previously inaccessible, ice-covered areas (Kelly et al. 2010b, Kovacs 2014).

It is predicted that, within the foreseeable future, the number of Arctic ringed seals will decline substantially, and they will no longer persist in substantial portion of their range (Kelly et al. 2010). Kovacs (2014) stresses the importance of developing and implementing an Arctic ringed seal monitoring program, given the ecological and subsistence importance of this species in the Arctic. See under ‘Status and Outlook’ for more details.

Things are indeed happening in the Arctic: see for example the figures below taken from the The Arctic Report Card: update for 2013 – Sea Ice (Perovitch et al.2013) and Greenland Ice sheet (Tedesco et al. 2013) in Jeffries et al. (2013).

Time series of Arctic sea ice extent anomalies in March (the month of maximum ice extent, black symbols) and September (the month of minimum ice extent, red symbols)(Perovich et al. 2015).


Monthly changes in the total mass of the Greenland ice sheet (Tedesco et al. 2015)

Monthly changes in the total mass of the Greenland ice sheet (Tedesco et al. 2015)

A range of human activities has the potential to degrade habitat important to ringed seal survival:

  • changing water quality and pollution (e.g. runoff from industry and agriculture, oil spills)
  • habitat disturbance and acoustic pollution from low-frequency noise (vessels, seismic surveys, military activities)
  • entanglement (e.g. in marine debris, fishing gear, etc.)

CONTAMINANTS

In addition to their direct toxicity, anthropogenic contaminants may affect resilience and increase susceptibility to disease in marine mammals (Reijnders and de Ruiter-Dijkman 1995).

Contaminant loads in ringed seals have been investigated in most parts of the species’ range (although not in the Sea of Okhotsk), reflecting the ringed seal’s importance in the diets of coastal people and polar bears (e.g., Dietz et al. 1998, Hyvarinen et al. 1998, Muir et al. 1999, Bang et al. 2001, Fisk et al. 2002, 2005, Sonne et al. 2002, 2009, Rigét et al. 2005, 2006, Dietz 2008, Wolkers et al. 2008, Sonne et al. 2009, Routti et al. 2009, and Kelly et al. 2010b and Kovacs 2014 for review). The levels of persistent organic pollutants (POPs), mercury, and radionuclides are particularly high in communities that have traditional dietary habits and consume a lot of marine mammal meat and blubber (e.g. Polder et al.2003). The Arctic Monitoring and Assessment Programme (AMAP) was estab­lished in the 1990s to address the risks and trends in contaminants in the Arctic, and ringed seals were selected as a key monitoring species because of their broad circumpolar distribution, high abundance, high trophic status and their frequency in the diet of coastal peoples (Wilson et al. 1998).

Pollutants such as organochlorine (OC) compounds and heavy metals have been found in all ringed seal populations, with males tending to have higher toxic loads than females for many substances. Relatively high levels of chlorinated hydrocarbons have been found in the blubber of ringed seals in some areas, probably as a result of atmospheric transport to the Arctic (Reeves 1998) and OC contamination is greater in the European Arctic than in the Canadian or U.S. Arctic (Borgå et al. 2005). In addition, metals including cadmium, mercury, zinc and selenium accumulate in other tissues (Dietz et al. 1998).

Mercury contamination is a particular problem for some freshwater populations, and is thought to have contributed to elevated mortality of ringed seal pups in Lake Saimaa (Sipilä and Hyvärinen 1998, Kostamo et al. 2002). Environmental contaminants have also been implicated as a factor in the reduced fertility of Baltic Sea seals, which has inhibited the recovery of the population (Härkonen et al. 1998, Harding and Härkönen 1999). For most other areas, however, there is little evidence that contaminants are an immediate threat to ringed seals (Kovacs 2014) and following restrictions on the use and release of POPs into the environment, levels of these substances are dropping rapidly in the Baltic and in the Arctic (e.g. Kostamo et al. 2002, Wolkers et al. 2008).

A suite of new-use chemicals previously unreported in the Arctic has recently been documented in arctic biota including ringed seals, however little information exists for these compounds in terms of spatial patterns, food web dynamics, or species differences in levels (Kovacs 2014). Kovacs underlines that although levels of these compounds are currently low, there is concern because some are increasing rapidly in concentration in some areas (e.g., polybrominated diphenyl ethers, Riget et al.2006) and some have unique toxicological properties. Some of these compounds were presumed to have low potential for long-range transport, and so were not expected to make their way into arctic biota. Kovacs also stresses that a better understanding of the effects of contaminants exposure is needed, especially given the risks of climate change stresses.

HABITAT DISTURBANCE AND ACOUSTIC POLLUTION

Reduction in sea ice cover due to global warming (see above) will likely lead to increased human activity in the Arctic in the form of shipping and resource extraction industries, with associated increased threats of marine accidents, pollution discharge and human created noise.

Increased oil exploration, exploitation and possible oil spills, drilling and shipping are potential threats to ringed seals in some areas. Ice breakers may directly disrupt the ice habitat of ringed seals, although this affects only a small area in relation to the total habitat available. Noise from shipping and industrial activities may disturb ringed seals and disrupt their activities, possibly leading to the abandonment of prime habitat (Reeves 1998). To date, the rather isolated and inaccessible habitat of ringed seals had provided them some protection from these threats.

Habitat disturbance, through manipulation of water levels, recreational snow machine operation, boating, tourism, shoreline construction, wind farms, etc., have been highlighted as specific threats for the Lakes Ladoga and Saimaa ringed seals (e.g., Sipilä and Hyvärinen 1998, Agafonova et al. 2007). Routine day-tourism seems to have caused the desertion of at least two previously used haulout sites at Lake Ladoga (Agafonova et al. 2007, Verevkin et al. 2006). As many as 2,000 wind generators are planned to be erected in Bothnian Bay, the main breeding area for Baltic ringed seals, but the impacts on ringed seals of the disturbance associated with the construction and operation of wind farms are unknown.

BY-CATCH AND COMPETITION WITH FISHERIES

Artic ringed seals have little interaction with commercial fisheries, both because they do not consume commercial fish species to any great extent, and because their distribution does not coincide with intensive fisheries in most areas. They are therefore seldom caught in fishing gear. However, capture in fishing gear and other negative impacts associated with fisheries is a major problem for the ringed seals in Lakes Saimaa and Ladoga (e.g., Sipilä and Hyvärinen 1998, Agafonova et al. 2007, Kovacs et al. 2012) and in the Baltic Sea (Härkonen et al. 1998). Young seals seem particularly susceptible to capture in nets. Bycatch alone accounts for 10-16% of the annual mortality of the Lake Ladoga population (Verevkin et al. 2006).

© C. Lockyer

GREENLAND

Research on ringed seal populations in Greenland has been ongoing for many years, and has been increasing since the early 1970s. Early research focused on monitoring the harvest (catch statistics, life history parameters, diet, contaminants), and then expanded to studying ringed seal movements, both using conventional tagging and satellite tracking. Later on distribution and abundance surveys were also conducted. Prominent in these research efforts has been the Greenland Institute of Natural Resources (GINR) in collaboration with the Danish National Environmental Research Institute, now the Danish Center for Environment and Energy (DCE) from Aarhus Universitet.

Scientists A. Rosing-Asvid (GINR) and D. Holland (NYU), inspecting equipment; the (green) seal capture/release net can be seen on the lower right. © D. Holland

Scientists A. Rosing-Asvid (GINR) and D. Holland (NYU), inspecting equipment; the (green) seal capture/release net can be seen on the lower right. © D. Holland

A tagging programme of ringed seals was initiated in September 2010 by the GINR in collaboration with DCE and hunters as part of a series of environmental studies in advance of possible hydrocarbon development. One ringed seal was instrumented in September 2010 at Cape Farewell and 12 ringed seal were instrumented in 2011 in Melville Bay, Northwest Greenland.

Tagging studies have provided information on ringed seal behaviour, which can differ significantly in different areas. Some places hold a high concentration of local stationary seals, whereas other areas have many migratory seals that swim long distances. It is a large and expensive task to identify the movement patterns of ringed seals throughout their distribution area. Fortunately for this research, oceanographers have become aware that satellite transmitters on seals can also be used to gather data on water temperature and salinity down through the water column when the seal dives (temperature and salinity profiles). The ringed seal is particularly useful because many ringed seals live in ice-filled waters where it can be impossible or very expensive and difficult to get around by boat. A new tagging programme was therefore initiated in 2010 for obtaining oceanographic data in the vicinity of outlet glaciers along the cost of Greenland (the Icefjord in Ilulissat in west Greenland, Cape Farewell in South Greenland and Helheim in East Greenland). The project is a collaboration between physical oceanographers from New York University (NYU) and biological oceanographers from GINR and the Sea Mammal Research Unit (UK). The specific purposes of the project are to further the understanding of the hydrographic conditions of the waters near the outlet glaciers along the coast of Greenland, and the behaviour of ringed seals that in habitat the fjords in such areas. From 2010 to 2013, 13 seals were instrumented with satellite relay data loggers (SRDLs) which can measure Conductivity/Temperature/Depth (CTD). The project continued in 2014 and is funded for at least 4 more years.

The collection of stomach samples and other tissues from the seal harvest in Aappilattoq, Cape Farewell, was initiated in the fall of 2009 and continued throughout 2010. The project’s aim was to identify the diet of seals in these areas and to look into ecological interactions. The location was chosen partly because all five species of seals common in Greenland are harvested there. All the practical aspects of this project were run by local people. Studies of contaminants in seals in West Greenland are carried out by DCE.

NORWAY

Ringed seals in Svalbard have been the subject of research efforts in a wide variety of subject areas, intermittently since the early 1980s. Prominent in these research efforts has been the Norwegian Polar Institute (NPI), which has been looking at population parameters, diet, habitat use, reproductive and general ecology, reproductive energetics, abundance at different fjords, diving behavior and physiology, and contaminant burdens. This body of research provides the basis for a meaningful data time series that will permit assessment of population and ecological trends.

In 2002 NPI began a dedicated monitoring programme for ringed seals as part of MOSJ (Monitoring of Svalbard and Jan Mayen), designed to explore important aspects of ringed seal population biology and ecology and provide the first comparative data in a time series for the population (Kovacs and Lydersen 2006). It focuses on density and abundance of ringed seals in selected fjords, trends in population parameters (age structure and vital rates), diet, genetics, condition and ‘health status’ (blubber-reserves, serum chemistry, parasite infestations), and contaminant burdens (POPs, heavy metals, toxaphenes).

The project ICE Ecosystems is a research programme that focuses on Arctic species that are dependent on ice in some part of their life cycles and are threatened by future climate change: ice fauna, zooplankton, polar cod, polar bears, ringed seals and ivory gulls. As part of the ICE ringed seal programme from 2010 to 2012, 38 ringed seals off Svalbard were instrumented with advanced satellite tags to get information on the life of the seals and their use of the sea ice outside the breeding and moulting periods. The satellite tags used in this research programme provide the standard information on where the seals are, how deep they are diving and for how long, but in addition they provide hydrographic data (salinity and temperature) as well as information that gives insight into primary production (chlorophyll levels) in the regions where the seals swim and dive. The field reports for the field season 2012 can be accessed here and here. Samples have also been collected in Kongsfjorden, for various ecotoxicological studies.

In 2013 tagging continued using various combinations of satellite tags and sensors that were deployed on males and females of different age classes. Data collection ended and analysis is underway. Sea ice has continued to decline markedly within the archipelago in recent years, with no sea ice formation at all taking place in most of Svalbard’s fjords in the winter of 2011 and spring of 2012. Instrumented animals tracked via ARGOs and GPS systems will document their responses to these unique conditions, which are likely precursors of what ringed seals will experience elsewhere in the decades to come (Lydersen and Kovacs, in Kovacs 2014).

Fitting a satellite tag to a ringed seal back at Svalbard. Scientists K. M. Kovacs and C. Hamilton (NPI) sitting over a ringed seal while gluing a satellite tag to its fur (left) prior to its release (right). © K.M. Kovacs and C. Lydersen, Norwegian Polar Institute, from ICE Ringed seals - 2nd field report.

Fitting a satellite tag to a ringed seal back at Svalbard. Scientists K. M. Kovacs and C. Hamilton (NPI) sitting over a ringed seal while gluing a satellite tag to its fur (left) prior to its release (right). © K.M. Kovacs and C. Lydersen, Norwegian Polar Institute, from ICE Ringed seals – 2nd field report.

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