ANTARCTICA WILDLIFE

Antarctic Birds
The most obvious and commonly seen animals of Antarctica are the birds. The species diversity is very low, for reasons already explained. Only 43 species of birds occur south of the Antarctic Convergence, nearly all of them seabirds. Many ornithologists believe that Wilson's Storm-petrel, which breeds by the millions in Antarctica, may be the most numerous bird in the world.

Penguins
These birds epitomize the Antarctic. Although the 17 species of penguins are all found in the southern hemisphere, most of them live north of the Antarctic Convergence; the Galapagos penguin actually lives at the equator. Of all the penguins, only the Emperor and Adélie are restricted to Antarctic habitats. All penguins are flightless and adapted for life in cold water, so even those found in the low latitudes are dependent upon cold water currents for their livelihood. Penguins are the most aquatic of the seabirds, and they spend most of their lives at sea, except when moulting or rearing young.

Their ancestors were flying birds, as shown by the similarities in their pectoral girdle to that of modern flying species. The main reasons why birds fly are to search for food, evade predators, and migrate; penguins fly underwater.

The wings of penguins are reduced in size, stiff and flat. They are adapted to propel the birds through the heavy medium of water. Unlike most birds, penguins swim by flapping their wings underwater rather than paddling with their feet.

Penguins are quite similar in appearance and behavior to the flightless great auk of the northern hemisphere (which became extinct in 1844). That bird had long been known by the name "penguin" in English, so when the first British sailors arrived in the southern oceans they transferred the name to the newly discovered flightless birds, simply because they looked like the familiar great auk.

Birds which can fly have lightweight or even hollow bones, and air sacs within the body to help reduce body weight and decrease the wing loading. Penguins, however, have dense, solid bones and no air sacs, in order to counteract buoyancy, and dive to great depths. Their bodies are very streamlined, but even so, when they stop moving their wings they slow down very quickly. To avoid coming to a halt each time they break the surface to breathe, penguins have developed a method of swimming termed porpoising.

This allows them to swim rapidly just below the surface and when necessary propel themselves out of the water in a low arc, take a quick breath, and continue on their way. This may also be useful in escaping from an underwater predator, such as a leopard seal. Most penguins can submerge for 5-7 minutes, but the largest species (the emperor penguin) can submerge for up to 18 minutes. The Emperor Penguin dives to 630 meters (2,070 feet). Most other species do not normally go deeper than about 100 meters (330 feet). Penguins' maximum swimming speed is probably about 24 kph (15 mph), but because of their small size they often seem to be traveling faster.

Penguins generally feed on prey captured near the surface, either close to shore or near the edge of pack ice. In Antarctica, the larger species feed primarily on squid, while the smaller species feed mostly on krill, with some fish and squid. During the summer months, however, krill is the main food item for all - as is evident from their typically pink-colored excrement. Virtually all penguins are social and nest in colonies.

In Antarctica, most species use open nests lined mainly with pebbles, but also other debris such as bones and feathers. The pebbles are collected from the beach or stolen from other nests. Both sexes share in incubating the eggs and feeding the young. The two largest species, the emperor and king penguins, make no nest at all, and since they require more time to raise their young, they lay their eggs in winter so that chicks can be fledged by the end of summer.

Emperor Penguin colonies are on the sea ice, unlike those of other penguins, which nest on land. The male Emperor incubates a single egg by balancing it on top of his feet and covering it with a special brood pouch (the same method is used by the king penguin). He must stand upright and shuffle around with the egg for about two months, while his mate is out at sea feeding. If the egg hatches before the female returns to relieve him, the male can feed the new-born chick with small quantities of crop secretions containing fat and protein.

In some penguin species the young form groups, or creches, which can then be guarded by just a few adults; this allows most of the adult penguins to spend longer at sea feeding. There is always a lot of activity at penguin colonies, and the sights, sounds, and smells are unforgettable. Incubation usually lasts 5 to 6 weeks.

The fledging period varies quite widely, with Adélies and Chinstraps leaving the colony at about seven weeks, while for gentoos the time is 14 weeks. The young are fed by regurgitation, and take the food from inside the mouths of the adults.

Penguins typically have very strong feet with large, well developed claws with which to climb slippery rocks or ice. Feathers account for about 80 percent of the penguins' insulative properties, while fat provides the other 20 percent. Penguins have a very high internal body temperature (about 38ºC or 101ºF) as well as a high metabolic rate. They have no problem surviving - indeed, thriving - in the cold, harsh climate of Antarctica.

Fauna

Mammals:
Antarctic fur seal - Arctocephalus gazella
Leopard seal - Hydrurga leptonix
Wedell seal - Leptonychotes weddellii
Crabeater seal - Lobodon carcinophagus
Southern elephant seal - Mirounga leonina
Humpback whale - Megaptera novaeangliae
Southern right whale -Eubalaena australis
Blue whale - Balaenoptera musculus
Fin whale - Balaenoptera physalus
Minkee whale - Balaenoptera bonaerensis
Southern bottlenose whale - Hyperoodon planifrons
Sperm whale - Physeter macrocephalus
Orca - Orcinus orca
Dusky dolphin- Lagenorhynchus obscurus
Commerson´s dolphin -Cephalorhynchus commersonii

Birds:
Emperor penguin - Aptenodytes forsteri
King penguin -Aptenodytes patagonicus
Adelie penguin - Pygoscelis adeliae
Chinstrap penguin- Pygoscelis Antarctica
Gentoo penguin -Pygoscelys papua
Macaroni penguin -Eudyptes chrysolophus
Rockhopper penguin -Eudyptes chrysocome
Wandering albatross -Diomedea exulans
Royal albatross -Diomedea epomophora
Black browed albatross -Thalassarche melanophrys
Gray headed albatross -Thalassarche chrysostoma
White capped albatross -Thalassarche cauta
Sooty albatross- Phoebetria fusca
Light mantled albatross -Phoebetria palpebrata
Northern giant petrel -Macronectes halli
Southern giant petrel -Macronectes giganteus
Souther fulmar - Fulmarus glacialoides
Antarctic petrel -Thalassoica antarctica
Cape petrel -Daption capense
Snow petrel -Pagodroma nivea
Kerguelen petrel -Pterodroma brevirostris
Great winged petrel -Pterodroma macroptera
Mottled petrel -Pterodroma inexpectata
Soft plumage petrel -Pterodroma mollis
White headed petrel -Pterodroma lessoni
Grey petrel -Procellaria cinerea
White chinned petrel -Procellaria aequinoctialis
Westland petrel -Procellaria westlandica
Blue petrel -Halobaena caerulea
Greater shearwater -Puffinus gravis
Little shearwater -Puffinus assimilis
Antarctic prion Pachyptila desolata
Thin billed prion -Pachyptila belcheri
Wilson´s storm petrel -Oceanites oceanicus
Grey backed storm petrel -Garrodia nereis
Black bellied storm petrel -Fregetta tropica
South Georgia diving petrel- Pelecanoides georgicus
Common diving petrel -Pelecanoides urinatrix
Kelp gull -Larus dominicanus
Antarctic -skua Catharacta Antarctica
South polar -skua Catharacta maccormicki
Snowy sheatbill -Chionis alba
Blue eyed shag -Phalacrocorax bransfieldensis
Antarctic tern -Sterna vittata
Arctic tern -Sterna paradisaea
South american tern -Sterna hirundinacea

Flora

Algae: Prasiola crispa (Lettuce like alga), Desmarestia (brown alga), Cystosphaera jacquinotii (brown alga with floats)
Mosses
Lichens
Hair grass Deschampsia antarctica
Pearlwort Colobanthus quitensis