Seals in the Arctic

Published by the Norwegian Polar Institute Lag rapport Les på norsk

Six different seal species are found around Svalbard and Jan Mayen – harp seal, hooded seal, common seal, ringed seal, bearded seal and walrus. Climate change is creating problems for several of them, because the sea temperature is rising with global warming and reducing sea and fjord ice cover in the Arctic.

Disappearing ice a problem for several species

In January 2013 and 2014 there was little sea ice around Svalbard. There was also limited ice cover and not much snow on the ice in a number of the fjords along the west coast of Spitsbergen these years. One of these fjords is Kongsfjorden, which has received a great deal of research attention in recent years. Measurements show that since 2006, higher water temperatures here have been preventing the formation of fjord ice.

Ringed seals and hooded seals in trouble

Ringed seals give birth to their pups in snow lairs on the fjord ice, and can only dig proper lairs if the ice is thick enough and there is sufficient snow cover. Pups on the ice surface are easy prey for polar bears, Arctic foxes and seabirds and are unlikely to survive the critical early weeks of life.

Ringed seals often return to their own birthplace to give birth. Changes in ice and snow conditions may therefore be a serious threat to the species.

Declining sea ice cover also causes problems for hooded seals during the whelping season at the end of March. Hooded seals are gregarious, and females congregate for the brief whelping season. They are dependent on large expanses of ice. The pups too face problems if the ice floes are too small, since they cannot leave the ice for the first few weeks after birth. Polar bears have been observed in the whelping areas in recent years, and predation may be another factor behind lower pup survival rates.

Large harp seal population in the Barents Sea

The harp seal population is the most abundant seal species in the region. One stock whelps near Jan Mayen (the West Ice) and the other in Russia, in the White Sea (the East Ice).

In 2012, it was estimated that there were about 631 000 adult seals in the West Ice and about 1.3 million in the East Ice. There were performed counts of the White sea population in 2013, but the results are not yet analyzed and published.

A large harvest was taken from the East Ice stock in the years after the Second World War, but strict regulation by quotas was introduced from 1965. Seal numbers rose rapidly after this, and catches of pups and adults were later increased again. However, numbers have declined considerably once more since 2000, and the catches have also been greatly reduced. Lower seal numbers are explained by a reduction in the area of drift ice and in ice thickness in the White Sea since 2000.

Northeast Atlantic hooded seals endangered

All hooded seals in the Northeast Atlantic are considered to belong to the same stock, which whelps in the West Ice. On the basis of aerial surveys, it was estimated that there were about 82 000 individuals in 2013. This corresponds to a decline of 80–90 per cent since the 1950s, and Norway therefore gave the stock protected status in 2007. It was also classified as endangered  in the 2010 Norwegian Red List. Projections of a continued decline in sea ice extent make the future of the species uncertain.

Moderate catches and lower pollution levels

Harp seals are still harvested in the West Ice, but in much smaller numbers than before. Norway discontinued  hooded seal catches after the 2006 season because of uncertainty about the stock trend.

Norway also permits catches of both ringed seals and bearded seals. Only small numbers are taken, and the Governor of Svalbard keeps hunting statistics for these species. Less is known about their population status, but there are indications that recruitment to the ringed seal population has been poor in the Svalbard area in recent years because of ice conditions.

Seals are carnivores, and are top predators in food chains. They are therefore vulnerable to accumulation of pollutants such as persistent organic pollutants (POPs) that contaminate their food. Levels of certain substances in Arctic seals have declined in recent decades, partly because of strict rules under the Stockholm Convention, which regulates the production and use of POPs.

Protection and harvesting within safe biological limits

The International Council for the Exploration of the Sea (ICES) publishes recommendations on catches of harp seals every five years. The stock is assessed at regular intervals on the basis of catch data, registration of pups and capture-mark-recapture surveys. The current harvest levels for harp seal, ringed seal and bearded seal appear to be within safe biological limits.

The common seal and walrus are protected species in Svalbard.