Emperor penguins (Aptenodytes forsteri) are the largest of all penguins, standing up to 4 feet tall and weighing in at a whopping 85 pounds. Like other penguins, they sport a black back and white chest markings, however bright yellow feathers around the neck are unique to the emperor species. Emperor penguins inhabit the open ice and small islands around the South Pole and nowhere else. Uniquely adapted to their harsh environment, emperor penguins spend most of their time hunting in the freezing water.
Existing only in the Antarctic, roughly 270,000 to 350,000 emperor penguins live in large colonies of up to a few thousand birds each. They are the only animal that can survive the extreme temperatures of the Antarctic winters, when wind-chill temperatures can plummet to minus 76 degrees Fahrenheit. To stay warm, emperor penguins huddle together and take turns moving from the outside of the crowd to the inside to warm up.
Unlike most other animals, which tend to mate in the spring, emperor penguins reproduce in the coldest part of winter. This timing allows the chicks to develop sufficiently so they're able to take to the water once the ice melts in the summer. The female lays a lone egg, then the male takes over and keeps the egg warm and protected until it hatches. While the males stand guard, huddling together in their enormous colonies to stay warm, the females leave for the open water to hunt for food. Unable to eat during the two months they're incubating eggs, the males must live off their fat stores. Once the females return, they assume the role of nurturing the chicks while the males return to the ocean to hunt for food.
Diet and Diving
Emperor penguins spend most of their time hunting for fish, squid and crustaceans in the open water. Unable to fly, they get around on land by foot. The penguins' wings, however, serve them well underwater, transforming the ungainly birds into graceful and astonishingly fast predators that can accelerate to speeds of 16 feet per second. Emperor penguins can dive deeper than any other bird, up to 1,800 feet, and a single dive can last up to 22 minutes, allowing them to reach prey other predators can't. The penguins power through the water, using their wings like other birds would in flight. However, unlike other birds that use only the downstroke of their wings to propel themselves, emperors are able to move forward by flapping both up and down.
Emperor penguins have evolved into efficient deep-sea hunters. They are equipped with powerful jaws and specialized barbed tongues, in which the spines point toward the back of the mouth. These adaptations prevent the prey from escaping before it can be swallowed whole underwater. Unlike birds that fly, emperor penguins have solid bones with very little airspaces; this gives the penguins less buoyancy, allowing them to dive deeper. Researchers believe emperor penguins are capable of cutting off the blood supply to nonessential parts of the body while diving, thus conserving energy and oxygen.
- Penguins-World.com: Emperor Penguin
- Animals -- Explore, Discover, Connect: Penguins
- A-Z Animals: Emperor Penguin
- National Geographic Animals: Emperor Penguin
- National Geographic News; "Penguin Ranch" Reveals Hunting, Swimming Secrets; James Owen; Jan. 30, 2004
- National Geographic News: Emperor Penguins: Uniquely Armed for Antarctica: Jennifer Hile; March 29, 2004
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