Ringed seals (Pusa hispida) are the most common and smallest seal species across the Arctic and sub-Arctic, with an estimated global population exceeding two million. These seals play a dual role in the Arctic food web, consuming fish and invertebrates while also serving as a primary food source for many other animals. This makes them a central component of the Arctic ecosystem.
The Primary Hunters
Polar bears (Ursus maritimus) are the primary predators of ringed seals, relying on them as a main food source. These large carnivores use diverse hunting techniques. They often wait patiently at seal breathing holes, a method known as “still-hunting,” detecting openings from nearly a mile away with their acute sense of smell. Polar bears also stalk seals basking on ice or ambush them in snow-covered birthing lairs. A single polar bear can consume a ringed seal every two to six days, primarily eating the energy-rich blubber.
Killer whales (Orcinus orca) prey on ringed seals more opportunistically or regionally. These intelligent marine mammals use coordinated hunting strategies in open water, often working in groups. One notable tactic is “wave-washing,” where several killer whales swim in unison to create large waves that dislodge seals from ice floes, making them vulnerable. They may also ram or bludgeon their prey.
Less Common Predators
Arctic foxes (Vulpes lagopus) often target ringed seal pups, particularly those born in snow lairs. They tunnel into these lairs to reach vulnerable pups, and their predation can account for significant pup mortality in some areas. Arctic foxes also opportunistically scavenge on seal remains left by larger predators.
Greenland sharks (Somniosus microcephalus) consume ringed seals, primarily as scavengers but also as opportunistic predators. These slow-moving sharks may target sick, old, or young seals, especially those resting near ice edges or in shallow waters. Larger Greenland sharks can prey on agile seals, often by surprising them.
Walruses (Odobenus rosmarus), though primarily feeding on mollusks, occasionally prey on seals. This behavior is more common among larger male walruses, who may use their tusks to subdue young or injured seals. While not their primary diet, seal consumption can become more prevalent when typical food sources are scarce or ice conditions limit access to preferred prey.
Why Ringed Seals Are Targeted
Ringed seals are susceptible to predation due to characteristics that make them an accessible food source. Their sheer abundance, with millions across the Arctic, ensures a consistent prey supply. Their relatively small size, averaging 1.5 meters (5 feet) and weighing 50 to 70 kilograms (110 to 150 pounds), makes them manageable for various predators.
The seals’ reliance on sea ice for critical life stages also exposes them to predators. They depend on sea ice for breeding, resting, and molting, maintaining breathing holes through thick ice that hunters can exploit. Ringed seals construct snow lairs on the ice for pupping, making them vulnerable to terrestrial predators like polar bears and arctic foxes. Their thick blubber layer, rich in fat and calories, offers a high-energy reward, providing essential sustenance in the nutrient-scarce Arctic.