Polar bears mostly go after high-fat seals for energy, but when seals get hard to find, they’ll eat other animals, plants, or even carcasses.
They hunt seals from the sea ice and really depend on seal fat to stay warm and make it through long stretches without food.
You’ll see how their main diet shapes the way they hunt, how mothers feed their cubs, and how melting ice pushes bears to try new foods.
Let’s dig into what seals, carcasses, birds, and even garbage reveal about a changing Arctic—and what all that means for these massive, hungry predators.
Polar Bear Diet: Core Foods and Feeding Habits
Polar bears mostly eat high-fat marine prey and use sea ice as their hunting ground.
They get most of their calories from seal blubber, but when they can’t find seals, they’ll take other marine mammals, carcasses, or even land foods.
Seals as Primary Prey
Seals really make up the backbone of a polar bear’s diet.
Ringed seals and bearded seals are especially important because they live and breathe through holes in the sea ice, right where polar bears wait.
Polar bears use their sharp sense of smell and a lot of patience to catch seals at breathing holes or on top of the ice.
Seal pups born in spring give polar bears a chance to put on weight fast.
During that time, bears eat the blubber-rich parts first, which helps them bulk up.
That blubber is packed with calories, keeping bears warm and fueling reproduction.
Other seals—like harp, hooded, and ribbon seals—sometimes end up on the menu if they’re around.
But honestly, ringed and bearded seals pack the most energy, so they matter most for healthy polar bear populations.
Marine Mammals and Carcasses
Polar bears also scavenge bigger marine mammals and carcasses along the coast.
When a beluga whale, bowhead whale, or walrus washes up, a polar bear will feast on the blubber and skin.
These big meals can last a bear for days when seal hunting doesn’t work out.
Walruses are tough and risky to hunt alive, but a young or weakened walrus—or a beached whale—offers a huge energy boost.
Other Arctic animals, like foxes and gulls, hang around to pick at what’s left.
Sharing these resources helps several species get through lean times.
Seasonal and Opportunistic Foods
Polar bears change up their diet depending on the season and what’s around.
In spring and early summer, they focus on seals.
When the ice melts in late summer, they might eat bird eggs, geese, seaweed, or small land mammals.
These foods help them survive short term, but they don’t have enough fat for long-term health.
Sometimes bears raid bird colonies for eggs or grab shorebirds when they can.
Scientists have noticed that in some places, bears eat more coastal foods as the ice shrinks.
But those foods just can’t compete with seals in terms of calories or nutrition.
Role of Fat Reserves in Survival
Fat reserves really decide how well polar bears survive.
Seal blubber under the skin and in the belly acts as both insulation and fuel.
Bears pile on thick layers of fat during good hunting to make it through fasting when the ice melts.
A well-fed polar bear can eat a ton of blubber in one sitting, storing up energy for months.
That fat keeps them warm, helps with pregnancy, and powers long swims between ice floes.
When hunting time gets shorter and fasting gets longer, bears lose weight, struggle to reproduce, and more of them die—especially cubs and older bears.
Blubber-rich prey is still the key to keeping polar bears healthy.
Diet Adaptations: Hunting Strategies, Cubs, and Environmental Changes
Polar bears depend on fatty seals for most of their calories, but they’ve learned to switch things up and try new tactics when ice or seals disappear.
You’ll see how they hunt, what cubs eat, which land foods they try, and how everything is shifting as the sea ice melts.
Hunting Techniques and Still-Hunting
Still-hunting is a classic move out on the sea ice.
A bear sniffs out a seal’s breathing hole, waits quietly nearby, and then lunges when the seal pops up.
This can take hours—or even days—so patience and a strong nose are a must.
Bears also sneak up on seals resting on the ice.
They crawl slowly, freeze if the seal looks up, then suddenly sprint to pounce.
When seals are hard to find, bears might follow whale carcasses or scavenge for big, calorie-rich meals.
You probably won’t see them bother with fish like salmon.
Fish just don’t have enough fat to be worth the effort.
What Do Polar Bear Cubs Eat
Cubs start out drinking their mother’s milk, which is super high in fat and helps them grow fast and stay warm.
Moms nurse their cubs in dens for about three months.
After that, mothers teach cubs to hunt and share the seals they catch.
Cubs mostly eat seal blubber and skin when their mom makes a kill.
They might nibble on bird eggs or small land animals, but those foods don’t provide enough fat.
Cubs really depend on their mom’s hunting skills and access to sea ice—if she can’t find seals, the cubs are in trouble.
Land-Based and Alternative Foods
When the ice melts back, you might spot bears eating more land foods.
They raid bird colonies for eggs, eat geese and seabirds, and scavenge whale or walrus carcasses that wash up.
Sometimes they eat berries, kelp, or the occasional small mammal like a lemming or leftover Arctic fox.
These foods help in a pinch, but they’re low in fat compared to seal blubber.
You’ll often see ravens and foxes tagging along to grab leftovers.
In places like Hudson Bay, bears spend longer on land and eat more alternative foods, but those still don’t replace the high-fat seal diet they need to build up fat.
Impact of Climate Change on Diet
As sea ice keeps shrinking with climate change, you’ll notice longer stretches without ice and much shorter hunting windows.
Bears end up fasting more or trekking farther just to find the last bits of ice. That means they get less time to build up the fat they need for survival and reproduction.
Some bears try to adapt by eating more land-based foods, but honestly, those just don’t have enough calories. When prey like ringed and bearded seals become harder to find, bears have to change up their behavior.
After a while, you’ll probably see bears with lower body weight. Fewer cubs survive, and there are more run-ins with people as hungry bears wander the coast searching for food.
If you want to dig deeper into how much polar bears rely on seals and sea ice, check out Polar Bears International’s page on diet and prey.
