You might think nothing eats polar bears, right? But here’s the real deal: adult polar bears have almost no natural predators. Cubs, though, can fall prey to other bears, wolves, killer whales, and—most of all—humans. That reality shapes how polar bears survive on Arctic ice and should make you think twice about their safety and future.
Let’s get into what actually eats polar bears at different ages. Why do adults stay at the top of the food chain? What do polar bears themselves hunt to make it through Arctic seasons? I’ll talk about cannibalism, pack hunters, and how changing sea ice brings new dangers for young bears—and, honestly, why humans matter a lot more than you might expect.
What Eats Polar Bears?
Polar bears usually rule their environment, but some animals and people still manage to kill or eat them. Adult bears rarely face danger from wildlife, but cubs and weak bears? They’re vulnerable to other bears, wolves, marine predators, and, of course, humans.
Cannibalism Among Polar Bears
Sometimes, adult male polar bears kill and eat cubs. In rare cases, they’ll even attack adult females.
This usually happens when food runs low or if a male stumbles on a female with young. Males are much bigger than females, so they can overpower them on the ice.
Females do their best to protect cubs by hiding in snow dens or sticking close on the ice. You might see males go after cubs that wander too far or when their mother’s exhausted from fasting.
When sea ice thins and seals get harder to catch, cannibalism becomes more common because bears get desperate for calories. Still, don’t assume cannibalism is the main reason cubs die—starvation and cold claim plenty of young lives, too.
Cannibalism, though, is a real part of polar bear life and can impact how many cubs survive in a given year.
Human Predators of Polar Bears
People have hunted polar bears for centuries—for meat, fur, and cultural traditions. Indigenous communities still harvest bears, following strict quotas in many places.
Beyond that, commercial hunting in the past and illegal hunting today have hurt some polar bear populations. When sea ice disappears and prey gets scarce, polar bears sometimes wander near settlements, which can lead to conflict.
Wildlife managers may have to remove or kill bears that threaten people. Humans also hurt polar bears indirectly by causing climate change, which shrinks sea ice and makes it harder for bears to find food.
If you ever head to polar bear country, please pay attention to local rules, carry deterrents, and don’t attract bears with food or garbage. The safety of both people and bears really depends on smart choices.
Wolves Preying on Polar Bear Cubs
Wolves sometimes take polar bear cubs, especially when cubs come ashore in the summer. Wolves hunt in packs and use teamwork to separate cubs from their mothers.
This risk grows as sea ice retreats and bears spend more time on land. A pack might distract an adult female while others grab a cub.
Cubs under a year old are especially at risk—they just can’t outrun or fight off several wolves. Healthy adult bears don’t attract much wolf attention; wolves focus on the small and isolated.
Some areas have seen more wolf attacks on cubs lately. It’s likely tied to shifting food webs and climate changes, which push wolves and bears into closer contact during certain times of year.
Killer Whales as Threats
Killer whales (orcas) have killed and eaten polar bears, but it doesn’t happen often. Orcas hunt in the water and might attack a bear that’s swimming or stuck on a floating ice chunk.
Melting ice forces bears to swim longer distances, which raises the risk. Most reports involve young bears or adults separated from solid ice near open water.
Orcas usually prefer seals, whales, and fish, so they don’t target polar bears regularly. Still, killer whales remain part of the Arctic food chain and can take advantage of a vulnerable bear.
If sea ice keeps shrinking, you might see more encounters between bears and orcas along the water’s edge.
Walruses and Rare Predatory Encounters
Walruses don’t normally hunt polar bears, but fights can turn deadly for a bear. Walruses defend themselves and their calves with huge tusks and sheer size.
If a bear gets too close to a walrus herd, it can end badly. Bears sometimes scavenge walrus carcasses or go after sick or young walruses, but these hunts can backfire if the walrus fights back.
Usually, the bear gives up and retreats. These incidents aren’t common, but they do happen, especially late in the ice season when bears get desperate for food.
Greenland Shark Scavenging
Greenland sharks don’t hunt polar bears, but they’ll scavenge bear carcasses in deep, cold water. These sharks live in Arctic and sub-Arctic oceans and eat all kinds of marine remains.
If a bear drowns or a carcass drifts out to sea, Greenland sharks might eat what’s left. This isn’t really predation—it’s just part of the scavenger clean-up crew in the Arctic.
You won’t find many cases of sharks attacking healthy bears on ice or in shallow water. Still, they help recycle nutrients after a bear dies.
Vulnerability of Polar Bear Cubs
Polar bear cubs face the most danger from both predators and the harsh environment. The first year is especially rough—cubs are tiny compared to adults and can’t travel far on thin ice or swim for long.
Adult males, wolf packs, and sometimes killer whales all pose threats. Cubs also die from starvation, cold, or if their mother can’t find enough seals.
If a den collapses or gets disturbed, cubs become easy targets for predators and the weather. Moms protect cubs by staying close and keeping to solid ice whenever possible.
If you’re in polar bear country, keeping your distance, not leaving attractants, and reporting sightings can help protect these vulnerable young bears.
What Do Polar Bears Eat?
Polar bears mostly eat high-fat marine animals. That’s how they build up fat reserves for the coldest months.
They hunt from sea ice, using a sharp sense of smell and a mix of stalking and ambush tactics to catch calorie-rich prey.
Seal Species as Main Prey
Ringed seals make up most of a polar bear’s diet. Bears wait at breathing holes or sneak up on seal haul-outs to grab seals with thick blubber.
Bearded seals are bigger, so one kill gives a bear a lot of meat and fat. Bears often go after them when ice edges and shallow areas make it easier.
Ribbon seals and harp seals show up in the diet in some areas, depending on where bears roam. Polar bears focus on the blubber and skin first—it’s the highest-calorie part.
Hunting depends on sea ice as a platform and the bear’s sense of smell to find seals from far away.
Marine Mammal Carcasses
Polar bears scavenge whale and seal carcasses when they find them. A washed-up beluga or dead walrus can feed a bear for days.
Sometimes, bears eat leftovers from human hunters near Arctic communities. Scavenging cuts down on hunting effort and risk, so it’s a big help when sea ice melts and seals get hard to catch.
Carcasses show up unpredictably, but they can make a big difference for a bear’s survival.
Land-Based Food Sources
When sea ice melts, bears turn to land foods—reindeer, muskox, small rodents, bird eggs, berries, and plants. These foods don’t have nearly as many calories as seal blubber, so they can’t really sustain adult bears for long.
In some places, bears chase down reindeer or muskox calves. You’ll also spot them raiding bird nests for eggs and chicks in the summer.
Land foods help bears last through longer ice-free periods, but they come at a cost. Hunting and traveling on land burns more energy than hunting on ice.
Seasonal Changes in Diet
Diet shifts with the seasons and whatever’s happening with the sea ice. In spring, hunting really ramps up on stable ice. Seal pups and moulting adults are around, so bears can finally pack on most of their yearly fat.
Summer’s a different story. The long stretches without ice force bears to scavenge more and look for food on land. Sometimes, they’re stuck fasting for ages.
Autumn brings a bit of hope as new ice forms and hunting chances return. But climate change keeps stretching those ice‑free periods. Bears end up fasting even longer and have to settle for lower‑calorie foods.
That means their fat stores drop, and it can mess with their ability to reproduce. The timing and reach of Arctic sea ice make or break a bear’s chances to eat well.
