The ecosystems and landscapes have been incessantly shifting around the world owing to climate change induced by human activities. This shift is rather dramatic at the poles — specifically the North Pole. Rising temperature in the Arctic region has been increasingly losing sea ice and snow; this has triggered a series of changes in its ecosystem which is leading to a loss of habitats for many plants and animal species. The ice-adapted species inhabiting the Arctic and sub-Arctic regions such as Ringed seals have been under a lot of stress as global warming threatens their crucial life cycles including breeding, protection of their pups, moulting and resting. Further, with the receding sea ice and snow, their exposure to humans and their activities has also increased.
Ringed seals (Pusa hispida), the smallest among all the seals, with their distinguished lighter grey rings on their dark pelts, are primarily found in the Arctic and sub-Arctic regions and are the most abundant of all seals. Mostly surviving on zooplankton and Arctic cods and herrings, they can dive as deep as 300 ft into the ocean and can remain submerged for 45 minutes. Listed as ‘Least Concern’ by the International Union for Conservation of Nature, some of the subspecies of ringed seals have been considered to be threatened or endangered. These ringed seals rely heavily on sea ice and snow for their reproduction and survival as a whole. However, they have been struggling to keep their pups alive because of the warming of the Arctic region due to climate change and subsequent changes in the albedo activity of sea ice and snow with their increased rate of melting.
They spend most of their time underwater hunting the schools of fish and depend on sea ice and snow for the birth and protection of their pups. Using their sharp claws on front flippers, they dug out breathing holes in the ice which serves a dual function of keeping them safe from their predators — the Polar bears — and helping them in getting oxygen. They require snow to build birth lairs — kind of snow caves or dens — which the female ringed seals construct on ice and snowdrift which provides shelter to their pups and protect them from harsh temperature and predators. It is during this time in lairs, mothers nurse their pups and pups begin to accumulate fat feeding on the rich milk of their mother. However, the rising temperature has impacted the snowfall, ice pack, snow depth in the region. In recent years, the springs have been warmer which has been resulting in early break up of ice. This, along with spring rain, puts the lairs at risk of collapsing and making the underdeveloped pups exposed and vulnerable to predators and cold temperature.
Scientists are not certain how climate change will impact the population of ringed seals. However, with the sea ice and snow getting lesser, the Arctic food web is bound to have an ambiguous fate and a cascading effect on the entire ecosystem. Without the accessibility to ringed seals, the Polar bears’ population will continue to decline as the ringed seals make their primary prey. Further, with seas opening more, the region is expected to see a rise in shipping and tourism development, fishing and oil exploration activities, which will increase the presence of humans in their icy habitat leading to its degradation and reduced food sources. To adapt to the ongoing and future threats which climate change and anthropogenic activities present to these ringed seals, they may have to look for suitable ice conditions and shift their territories!
