Just a look at a seal’s skull gives you a hint as to what makes up its diet. If you didn’t know better, you’d think it was the skull of a wolf, with its fangs and carnassial teeth meant for grabbing and shearing meat. Indeed, seals are carnivores. They’re not only carnivores but are quite skilled and persistent hunters. The difference is that wolves hunt on the land while seals hunt in the ocean. To help them do this, nature has not only equipped them with fangs but flippers, torpedo-shaped bodies, and layers of blubber if they make their living in the colder seas.
Seals are members of the Pinnipedia order, which is divided into three families and about 34 species. Two include the true seals, the fur seals, and sea lions. The 10 foot long, one-ton walrus with its famous tusks make up a family of its own. Read on to learn what makes up the seal’s diet and how it gets its food.
What Foods Do Seals Eat?
As carnivores, seals eat aquatic animals, mostly fish. However, some seals have a surprisingly varied diet. The endangered New Zealand sea lion, for example, eats not only fish but squid and octopus and crustaceans such as shrimp. It will even eat other seals and has been known to catch and eat insects and seabirds.
The walrus appears to be an invertebrate specialist. It takes mollusks, marine worms, sea cucumbers, sea squirts, and other tunicates and soft coral. It hunts along the bottom of the sea and can find prey through its sensitive whiskers. It uses its flippers and blows jets of water into the seabed to clear it. When a walrus finds prey, it grips it with its lips and sucks the meat out of the shell. The walrus rarely eats seabirds and bits of other seals and might scavenge if it finds a dead whale.
The Antarctic fur seal’s diet is mostly krill, but they’ve been known to eat penguins. Harbor seals have been known to eat ducks, and gray seals have been known to eat harbor porpoises. These porpoises can grow to over six feet long and weigh 168 pounds, but grown gray seal bulls are larger. They can be over seven feet long and weigh 680 pounds.
How Do Seals Hunt Prey?
Some seals, such as the California sea lion, hunt cooperatively with dolphins who can corral great schools of fish. Many seals range far and wide and dive deeply to hunt for prey. The Weddell seal can dive as deep as 1968.5 feet and stay submerged for an hour looking for prawns and other bottom feeders. Harbor seals can swim as far as 31 miles from their resting areas and stay out there for days looking for food.
Northern elephant seals swim as much as 13,000 miles through the ocean in search of food and don’t return to land until it’s time to reproduce and molt. Not only this, but they can dive to over 5000 feet and hold their breath for close to two hours. They also have several physical adaptations that allow them to conserve energy and oxygen while they’re diving.
The leopard seal has a good repertoire of hunting strategies. It stalks penguins along the edges of the ice where the bird lives. When the penguin comes into the water, the seal grabs its feet and shakes and bashes it to death. It then rips the animal into manageable pieces. Like the walrus, the leopard seal uses suction to eat small fish. When it hunts for krill, the leopard seal uses filter feeding. Its back teeth come together in a way that lets it strain krill from the ocean. This is also true of the crabeater seal. The crabeater seal, by the way, doesn’t eat crabs so much but specializes in krill.
The ribbon seal of the North Pacific Ocean have weaker fangs than some other seals, and they hunt their prey by piercing them with their teeth and swallowing them whole as opposed to tearing them to pieces.
Monk seals forage on the bottom of the sea and have been seen flipping over rocks to look for prey. Still, as fast swimmers they can pursue prey in open water.
A study of harbor seals revealed they participate in cooperative hunting, as do many other types of seals. Anywhere from 2-8 seals may hunt together. Findings were unable to prove that this style was more successful than individual hunting, however.
Some seals have different strategies depending on the time of day. The Baikal seal uses its eyes to search for fish during the day, while at night it uses touch to find crustaceans.
What Animals Eat Seals?
Seals only look cute. They are large and aggressive animals and don’t have too many predators, though humans have done a number on their numbers. Most seals are taken as pups or if they are sick or weakened. Animals that eat seals include:
- Humans
- Great White Sharks
- Other seals
- Killer whales
- Mako sharks
- Polar bears
- Arctic foxes
- Tiger sharks
- Galapagos shark
Up Next…
Intrigued? Let’s seal the deal with more pinniped facts!
- 10 Incredible Sea Lion Facts True socialites, sea lions are fascinating creatures who will talk your ear off!
- 10 Incredible Leopard Seal Facts Wait to you hear how these seals hunt penguins!
- 10 Incredible Elephant Seal Facts Find out why they are called “elephant” seals!
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