Please note: It is rare to see ringed seals on our Churchill polar bear adventures, except potentially by helicopter. A scenic helicopter flight is included on our Ultimate Churchill Adventure and Churchill Arctic Family Adventure, and available as an optional excursion on all other polar bear adventures.
Reaching population levels near 6 or 7 million, the ringed seal is the most plentiful, pervasive and common seal of the Arctic. It is the most significant seal supporting the diet of indigenous peoples who inhabit the Northwest Territories. Living in the Northern Hemisphere’s circumpolar regions, the ringed seal gravitates to habitats comprised of pressure ridges, leads
and polynyas in the Arctic Ocean’s land-fast ice, which is sea ice that forms in shallow water off the coast.
Compared to other seals, ringed seals are small. Males typically weigh between 145 and 200 pounds and measure slightly more than 4 feet long, while females average 100 to 110 pounds. Rigid guard hairs comprise their light gray coats, which can display varied patterns, but always have black spots surrounded by lighter ring markings (giving them their name). Spots on their backsides often merge with each other so they appear like a stripe instead of a spot. Their undercoat is lighter and their bellies are usually clear, silvery-white to creamy yellow, and scattered with black spots.
Using their well-honed sense of smell, hearing
and vision, curious ringed seals often investigate unknown sounds and sights. Lounging seals continuously alternate between lying flat and lifting their heads skyward for a few moments. They utilize a variety of vocalizations including moans, whines, and growls, and they frequently heed cautions sent by other seals.
Though they periodically group up at haul-out areas or move in groups that are loosely organized, ringed seals are chiefly solitary beings. During winter, they separate according to age; adults stay in preferred breeding habitats, under stable ice in bays and fjords, while non-breeders remain at the edge of the floe where they move based on availability
of food and population pressures.
In the water, seals utilize holes within the ice for breathing; they keep these holes open by using their fore flippers to claw the ice. Cone-shaped and covered with an ice dome perforated by a tiny vent, seals can hollow out the breathing hole if snow blows over it. Prior to surfacing, seals may blow bubbles through the hole to check for predators.
Seals have a number of physiological adaptions that allow them to dive deep into the icy ocean. They possess a high number of red blood cells, control the quantity of blood flowing to vital organs, and decrease their heart rate from 80-90 beats per minute to as low as 10–20. Average dives for food last approximately 3 minutes, interspersed with 1.5-minute intervals for breathing at the surface. Ringed seals can dive to depths of 295 feet for up to 45 minutes.
A ringed seal’s diet consists of a wide array of fish and crustaceans, including shrimp, arctic cod, crab and herring. They fast while molting, basking and mating.
At 5 to 10 years of age, ringed seals reach sexual maturity. After 10 years old, females have a high annual rate of pregnancy. Males who mate will become territorial and possess a musky, potent odor. April is peak breeding season. After mating, the embryo remains undeveloped for 81 days, after which gestation lasts nine months.
Pregnant females will find a snow cave, or dig a birthing den out of a snowdrift above a breathing hole. Seal pups are usually born between mid-March and early April, averaging 2 feet long and 10 pounds at birth. Pups have fine, soft white hair, called “lanugo,” which sheds by 8 weeks old. This keeps them warm until they gain the layer of blubber needed for insulation. Molted pups have a silvery coat of hair on their belly and a dark gray back. They are known as “silver jars.”
Mothers give birth to a single pup, nursing them for five to eight weeks in the sheltered warmth of the protected den. Males play no part in caring for their pups. Females leave their young when the ice begins to break up, usually in late June or early July. At 1 year old, young are about 70 percent of their mature size.
The ringed seal’s many predators include polar bears, arctic fox, walruses, wolves, dogs, wolverine, sharks, gulls, and humans—more than 25 percent of the pups in their dens are eaten by arctic foxes. Ringed seals are the main prey of polar bears, which will catch one seal about every five and a half days.
By Shawn Dahle, NOAA, Polar Ecosystems Program research cruise (NOAA) [Public domain], via Wikimedia Commons