Instead, they have evolved into the most efficient swimmers and divers of all birds. Penguin wings are stiff, short flippers to propel them underwater — they literally fly through the sea. Their legs are set far back in the body, and together with the tail form an underwater rudder to their perfectly streamlined bodies. Their cruising speed in water is about 10km per hour. To catch their breath and to save energy while swimming, they leap clear of the water every few metres.
They are excellent divers, descending to depths of over metres, though most of their dives will be in the top 10 metres. Unlike flying birds, their bones are dense to make diving easier. Underwater they are every bit as fearsome to their prey as lions are to theirs! However, penguins are rarely seen underwater, so our main impression of them is confined to how they appear on land.
With their legs set far back for efficient movement underwater, the penguins walk awkwardly in a very upright position. This is possibly the reason for their extraordinary appeal — they look like funny little people. Even on land, penguins are surprisingly agile. Some penguins are able to hop up great heights compared to their size.
To penguins, swimming in warm seas is like walking around in winter clothes in the height of summer! The warm waters of the equator are a barrier to penguins. Even the penguins living close to the equator stick to the cooler water coming from the south.
If penguins could travel to the Arctic, they would find their niche already taken by another bird — the puffin. Puffins are also black and white birds with colourful beaks.
However, puffins need to be able to fly to escape land-based predators. Penguins cope well in the cold — some breed in the coldest conditions in the world. Their short outer feathers overlap, like tiles on a roof, to form a thick waterproof layer, and underneath are fluffier feathers for warmth.
Like seals and whales, a thick layer of fat under the skin provides insulation and extra reserves for when food is scarce. Read about penguin mega-colonies discovered in Antarctica. In the ocean, though, penguins most contend with leopard seals , formidable hunters that specialize in warm-blooded prey. Dubbed the unicorn of the sea due to their long, spiraled tooth, narwhals are a beloved Arctic animal that, like other porpoise species, can be spotted swimming in groups of dozens or even hundreds of animals.
The narwhal is a year-round Arctic resident, summering in ice-free coastal waters. When faced with impenetrable coastal ice, these marine mammals move offshore, into deeper waters, to feed under shifting pack ice. They use cracks and openings in the ice to breathe. Read more about the mystery of the sea unicorn. The predators, which have a life expectancy of at least years , eat whatever they catch or scavenge, from unwary fish or seals to carcasses of polar bears or caribou.
The icefish species Chaenocephalus acteratus are also notable as the only vertebrates with no red blood cells; their white blood gives them a ghostly appearance. Read about a new species of see-through fish discovered in Antarctica. Orcas , or killer whales, live in many oceans worldwide, including those around Arctic and Antarctica.
About 70, orcas live in southern waters, where they specialize in different foods. Eisert has observed Type C orcas swimming at least a mile under a sheet of ice—a risky behavior for air-breathers.
See exclusive footage of rarely seen Type D orcas. Its black tail gives it a tuxedo-like appearance. Travel with us to Antarctica to see these animals and more.
In the Arctic, on the other hand, seals are aware of their place on the food chain—a notch below terrestrial predators like polar bears, foxes, wolves, and humans.
In the Arctic, you can't walk closer than about feet to a ringed seal before it flees. Weddells also birth their pups right on the ice, while ringed seals hide them in a snow-covered lair. The Arctic tern has the longest commute in the world: About 44, miles each year on a roundtrip migration between Greenland, where it breeds, to Antarctica.
Dolittle, Naveen has been going to Antarctica for more than 30 years — what amounts to more than six years in real time, and counting penguins for the past 20 years. Why bother? Counting penguins in Antarctica, he says, is one of the best ways to track the impact of climate change and ocean health in the world's most pristine scientific laboratory.
The Antarctic Peninsula, the part of the continent that sticks out toward South America where many penguin species live, has warmed a whopping 5 degrees in the past 60 years, one of the most dramatic increases anywhere on Earth. The news wasn't all bad. Penguins are flightless birds that are highly adapted for the marine environment. They are excellent swimmers and can dive to great depths.
Emperor penguins can dive to over m. Their shape makes them extremely agile underwater. They use their feet and tail as a rudder, and propel themselves with their flippers. Penguins have a waterproof coat of short, overlapping feathers.
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