Penguins are the most common birds in Antarctic, and are specially adapted for its cold environment. Penguin feathers are very stiff, short and densely packed in order to help the birds conserve heat and swim. Penguins have very strong wing muscles and can paddle up to 25 mph. Many penguins also have thick layers of fat for insulation (just like whales!). Penguins will breed at the same time and form colonies on land when they do. One penguin will typically guard the young, while the other heads out to forage for food. Penguins survive by eating fish, krill and some crustaceans, but they have to be careful whenever they search for food because a leopard seal or killer whale could munch on them!
A baby Gentoo Penguin on Peterman Island
Whales are the largest creatures in the Southern Ocean. Many of them undergo long migrations, feeding in rich Antarctic waters during the austral summer, and breeding in the winter at lower latitudes. In the 19th and early 20th centuries commercial whaling decimated whale populations in the Southern Ocean which led to a worldwide ban on whaling. However, whales are still in danger as Japanese and Norwegian fisherman continue to circumvent the ban.
Many of the Southern Whales, including the blue whale, earth's largest animal, feed on krill by filtering them through baleen plates in their mouth. In the Ocean, the largest creatures feed off some of the smallest!
The Antarctic continent is a harsh environment for life. The temperature on most of the mainland never rises above freezing and the continent is covered in ice. Only some hardy lichens are able to survive inland. However, the Southern Ocean surrounding Antarctica is one of the most amazing ecosystems on earth and is home to a variety of incredible creatures.
Antarctic organisms in this marine ecosystem include:
Only in Antarctica
Many of these species are found only in Antarctica(species found in only one area are called endemic). Since Antarctica was only discovered 180 years ago, these native species are not used to seeing people, which leads to one of the most exciting traits of Antarctic wildlife. They are just as curious about you as you are about them! For visitors in Antarctica this means that most organisms can be approached without them running away, and for researchers this means that certain animals (including birds) can be easily picked up and measured. Be warned though, Antarctic treaties forbid touching any of the animals!
Well not as big or as glamorous as the penguins or whales, the krill are vastly more important as they provide food for both creatures. Krill are shrimp like creatures about 6 cm long and typically live for 5 years(if not eaten first!) They usually travel in dense swarms that can range in size from just a few meters to several miles. The swarms can contain more than 10,000 krill in just one cubic meter of water, and when whales find them exciting feeding frenzies often result!
Small, freefloating and microscopic, phytoplankton are responsible for providing all the food for the marine ecosystem as well as the air we breath! Phytoplankton is the general name given to single celled plants that are able to turn the suns light into food energy through photosynthesis(a side product of this reaction is oxygen, and without phytoplankton there wouldn't be any of it for us to breath). There are a wide variety of organisms that fall into the phytoplankton category, and together they form the basis of the antarctic food pyramid. Phytoplankton are eaten by larger nonsynthetic zooplankton, which in turn are eaten by krill, whales and larger organisms. Because Phytoplankton are such important producers, a major goal of oceanographic research is to determine what controls their population size and distribution throughout the Antarctic.
A common sea-ice diatom, Nitzschia stellata
Image: Fiona Scott
© Australian Antarctic Division 2002
Kingston Tasmania 7050
The infamous Antarctic Leopard Seal
6 types of seals inhabit Antarctica, including Crabeater, Weddell, Ross, Fur, Southern Elephant and Leopard. All the Antarctic seals, except the fur, are true seals (meaning they have no ears). Seals can navigate using sonar and can easily stay underwater for 30 minutes. Many seals feed off krill, including the Leopard seal, which is also famous for eating foraging penguins and younger seals. Leopard seals are so vicious that Antarctic divers immediately get out of the water when they approach, as they have already taken one human live.
Birds, not including penguins, are the most common visitor to a ship in Antarctic waters. Antarctic Birds include a large variety of Albatross, Petrels, Prions and Terns. These birds are truly incredible creatures. The Wandering Albatross has a wing span over 3 meters and can spend months flying at sea without ever stopping. Although they normally travel around 15 mph, they have been recorded travelling as fast as 50! Albatross are currently threatened because thousands die every year when they get caught on fishlines. Skuas are other large Antarctic birds that will dive bomb penguins to eat them!