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Photos: See the World's Cutest Sea Creatures

Walrus

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(Image credit: NOAA/Captain Budd Christman)

What is it about the plaintive dark eyes of a harbor seal, or the adorable whiskers of an otter? Even seahorses have a charm of their own. Here are some of the cutest sea animals out there.These huge mammals have distinctive flippers and long curved tusks. Males use these elongated teeth to fight for dominance; they're also helpful for digging in ice.

Harbor seal

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(Image credit: New England Aquarium)

These pinnipeds live along the coasts of North America, Europe and Asia. They use their distinctive whiskers to sense the movement of prey, including fish, shrimp and squid. This Harbor seal is named Amelia, and lives at the New England Aquarium in Boston.

Octopus

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(Image credit: Marc Tule/Scripps)

Though these slimy, slinky eight-armed mollusks are a bit creepy they have no skeleton so can morph their body to squeeze through tight spaces they can be quite endearing. For one thing, they're probably the most intelligent of all invertebrates (they're very good at getting out of tanks when kept as pets) and their staring eyes have a soulful look about them.

Harp seal

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(Image credit: NOAA)

While they are greyish when grown, harp seals are fuzzy and white as babies. Their plaintive black eyes stare out from their light faces heart-meltingly.

Green turtle

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(Image credit: Courtesy U.S. National Oceanic and Atmospheric Administration (NOAA))

These reptiles are sea turtles that swim great distances between where they feed and where they hatch eggs. Due to hunting and egg scavenging, as well as run-ins with fishing boats and nets, this species is endangered. Additionally, light pollution can disorient newly-hatched baby turtles, and sea pollution and habitat loss is a problem.

Sea otter

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(Image credit: Dreamstime)

These furry mammals swim around on their backs and balance snacks on their bellies while they chew away. They are native to the North Pacific Ocean. Sea otters used to be hunted for their fur, and consequently experienced a precipitous decline in population. Conservation efforts, including an international hunting ban, have helped those numbers climb, though the species is still considered endangered.

Lionfish

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(Image credit: Scripps)

These striped fish have a morose, Eeyore-like expression that give them a rather pathetic-yet-lovable look. But don't let that face fool you: Their spikes are actually venomous, and they use them to defend themselves against predators. Luckily, they are not aggressive toward humans. They are found in the Indian Pacific Ocean but this one was on display at the Birch Aquarium at Scripps Institution of Oceanography at the University of California-San Diego.

Beluga whale

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(Image credit: Georgia Aquarium)

These pale whales with their dark eyes and big heads have a very distinctive and winning look. They are found only in the frigid waters of the Arctic, and are highly sociable. They travel in pods, and mothers stay with their babies for at least two years.

Starry smooth-hound shark

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(Image credit: Edward Farrell)

Even sharks, stereotyped as the meanies of the sea, have a softer side. While adults of this species can grow to over 3 feet (1 meter) long, the babies are cute itsy bitsy sharklings. They're not particularly fierce, either: they mostly feed on bottom-dwelling shellfish. Once abundant in the Mediterranean Sea and southern European waters, years of overfishing have vastly diminished their populations.

Chinstrap penguin

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(Image credit: Courtesy U.S. National Oceanic and Atmospheric Administration (NOAA))

These penguins are found on the islands and icebergs around Antarctica. Here, penguins waddle on Seal Island, Antarctica. Penguins are flightless birds who spend much of their time in water.

Bottlenose dolphin

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(Image credit: NOAA Beaufort Lab)

Perhaps the most iconic and beloved of all cute sea creatures, the bottlenose dolphin has a smile built into its snout. These social animals live in pods, and are quite intelligence. Their brains make them not only great for show tricks at aquariums; they've also been trained to locate sea mines.

Clara Moskowitz
Clara has a bachelor's degree in astronomy and physics from Wesleyan University, and a graduate certificate in science writing from the University of California, Santa Cruz. She has written for both Space.com and Live Science.