Antarctica And Its Animals
The wildlife of Antarctica are extremophiles, having adapted to the dryness, low temperatures, and high exposure common in Antarctica. The extreme weather of the interior contrasts to the relatively mild conditions on the Antarctic Pinsula and the subantarctic islands, which have warmer temperatures and more liquid water. Much of the ocean around the mainland is covered by sea ice. The oceans themselves are a more stable vironmt for life, both in the water column and on the seabed.
There is relatively little diversity in Antarctica compared to much of the rest of the world. Terrestrial life is conctrated in areas near the coast. Flying birds nest on the milder shores of the Pinsula and the subantarctic islands. Eight species of pguins inhabit Antarctica and its offshore islands. They share these areas with sev pinniped species. The Southern Ocean around Antarctica is home to 10 cetaceans, many of them migratory. There are very few terrestrial invertebrates on the mainland, although the species that do live there have high population dsities. High dsities of invertebrates also live in the ocean, with Antarctic krill forming dse and widespread swarms during the summer. Bthic animal communities also exist around the contint.
Over 1000 fungi species have be found on and around Antarctica. Larger species are restricted to the subantarctic islands, and the majority of species discovered have be terrestrial. Plants are similarly restricted mostly to the subantarctic islands, and the western edge of the Pinsula. Some mosses and lichs however can be found ev in the dry interior. Many algae are found around Antarctica, especially phytoplankton, which form the basis of many of Antarctica's food webs.
Antarctic Life And Ecosystems — Science Learning Hub
Human activity has caused introduced species to gain a foothold in the area, threating the native wildlife. A history of overfishing and hunting has left many species with greatly reduced numbers. Pollution, habitat destruction, and climate change pose great risks to the vironmt. The Antarctic Treaty System is a global treaty designed to preserve Antarctica as a place of research, and measures from this system are used to regulate human activity in Antarctica.
Any precipitation that does fall usually falls as snow, and is restricted to a band around 300 kilometres (186 mi) from the coast. Some areas receive as little as 50 mm (2.0 in) of precipitation annually. The coldest temperature recorded on Earth was −89.4 °C (−128.9 °F) at Vostok Station on the Antarctic Plateau.
The dry interior of the contint is climatically differt from the western Antarctic Pinsula and the subantarctic islands. The Pinsula and the islands are far more habitable; some areas of the pinsula can receive 900 mm (35.4 in) of precipitation a year, including rain, and the northern Pinsula is the only area on the mainland where temperatures are expected to go above 0 °C (32 °F) in summer.
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The contintal shelf surrounding the mainland is 60 to 240 kilometres (37 to 149 mi) wide. The depth of the seafloor in this area ranges from 50 to 800 metres (164 to 2, 625 ft), with an average of 500 metres (1, 640 ft). After the shelf, the contintal slope descds to abyssal plains at 3, 500–5, 000 metres (11, 483–16, 404 ft) deep. In all these areas, 90% of the seafloor is made up of soft sedimts, such as sand, mud, and gravel.
At least 235 marine species are found in both Antarctica and the Arctic, ranging in size from whales and birds to small marine snails, sea cucumbers, and mud-dwelling worms. The large animals oft migrate betwe the two, and smaller animals are expected to be able to spread via underwater currts.
However, among smaller marine animals gerally assumed to be the same in the Antarctica and the Arctic, more detailed studies of each population have oft—but not always—revealed differces, showing that they are closely related cryptic species rather than a single bipolar species.
What Animals Live In Antarctica?
Antarctica's cold deserts have some of the least diverse fauna in the world. Terrestrial vertebrates are limited to subantarctic islands, and ev th they are limited in number.
Antarctica, including the subantarctic islands, has no natural fully terrestrial mammals, reptiles, or amphibians. Human activity has however led to the introduction in some areas of foreign species, such as rats, mice, chicks, rabbits, cats, pigs, sheep, cattle, reindeer, and various fish.
The bthic communities of the seafloor are diverse and dse, with up to 155, 000 animals found in 1 square metre (10.8 sq ft). As the seafloor vironmt is very similar all around the Antarctic, hundreds of species can be found all the way around the mainland, which is a uniquely wide distribution for such a large community. Polar and deep-sea gigantism, where invertebrates are considerably larger than their warmer-water relatives, is common in this habitat.
Antarctic Animals Size Comparison Poster (lehrer Gemacht)
These two similar types of gigantism are believed to be related to the cold water, which can contain high levels of oxyg, combined with the low metabolic rates (slow life) of animals living in such cold vironmts.
The rocky shores of mainland Antarctica and its offshore islands provide nesting space for over 100 million birds every spring. These nesters include species of albatrosses, petrels, skuas, gulls and terns.
The insectivorous South Georgia pipit is demic to South Georgia and some smaller surrounding islands. Ducks, the South Georgia pintail and Eaton's pintail, inhabit South Georgia, Kerguel and Crozet.
Incredible Animals That Live In Antarctica
The flightless pguins are almost all located in the Southern Hemisphere (the only exception is the equatorial Galapagos pguin), with the greatest conctration located on and around Antarctica. Four of the 18 pguin species live and breed on the mainland and its close offshore islands. Another four species live on the subantarctic islands.
Emperor pguins have four overlapping layers of feathers, keeping them warm. They are the only Antarctic animal to breed during the winter.
And eelpouts (Zoarcidae). Together the snailfish, eelpouts and notothioids (which includes cod icefish and several other families) account for almost 9 ⁄10 of the more than 320 described fish species in the Southern Ocean. Ts of undescribed species also occur in the region, especially among the snailfish. If strictly counting fish species of the Antarctic contintal shelf and upper slope, there are more than 220 species and notothioids dominate, both in number of species (more than 100) and biomass (more than 90%).
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In addition to the relatively species-rich families, the region is home to a few species from other families: hagfish (Myxinidae), lamprey (Petromyzontidae), skates (Rajidae), pearlfish (Carapidae), morid cods (Moridae), eel cods (Muraolepididae), gadid cods (Gadidae), horsefish (Congiopodidae), Antarctic sculpins (Bathylutichthyidae), triplefins (Tripterygiidae) and southern flounders (Achiropsettidae). Among fish found south of the Antarctic Convergce, almost 90% of the species are demic to the region.
Cod icefish (Notothiidae), as well as several other families, are part of the Notothioidei suborder, collectively sometimes referred to as icefish. The suborder contains many species with antifreeze proteins in their blood and tissue, allowing them to live in water that is around or slightly below 0 °C (32 °F).
There are two icefish species from the gus Dissostichus, the Antarctic toothfish (D. mawsoni) and the Patagonian toothfish (D. eleginoides), which by far are the largest fish in the Southern Ocean. These two species live on the seafloor from relatively shallow water to depths of 3, 000 m (9, 800 ft), and can grow to around 2 m (6.6 ft) long weighing up to 100 kg (220 lb), living up to 45 years.
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The Antarctic toothfish lives close to the Antarctic mainland, whereas the Patagonian toothfish lives in the relatively warmer subantarctic waters. Toothfish are commercially fished, and illegal overfishing has reduced toothfish populations.
An unusual species of icefish is the Antarctic silverfish (Pleuragramma antarcticum), which is the only truly pelagic fish in the waters near Antarctica.
While females of the smallest, the Antarctic fur seal (Arctophoca gazella), reach only 150 kilograms (331 lb). These two species live north of the sea ice, and breed in harems on beaches. The other four species can live on the sea ice. Crabeater seals (Lobodon carcinophagus) and Weddell seals (Leptonychotes weddellii) form breeding colonies, whereas leopard seals (Hydrurga leptonyx) and Ross seals (Ommatophoca rossii) live solitary lives. Although these species hunt underwater, they breed on land or ice and spd a great deal of time there, as they have no terrestrial predators.
Differences Between The Animals In The Arctic And Antarctica
The New Zealand sea lion (Phocarctos hookeri), one of the rarest and most localised pinnipeds, breeds almost exclusively on the subantarctic Auckland Islands, although historically it had a wider range.
There are 10 cetacean species found in the Southern Ocean; six bale whales, and four toothed whales. The largest of these, the blue whale (Balaoptera musculus), grows to 24 metres (79 ft) long weighing 84 tonnes. Many of these species are migratory, and travel to tropical waters during the Antarctic winter.
Orcas, which do not migrate, nonetheless regularly travel to warmer waters, possibly to relieve the stress the temperature has on their skin.
Antarctica Toob Educational Toy For Kids
Most terrestrial invertebrates are restricted to the subantarctic islands. Although there are very few species, those that do inhabit Antarctica have high population dsities. In the more extreme areas of the mainland, such as the cold deserts, food webs are sometimes restricted to three nematode species, only one of which is a predator.
Many invertebrates on the subantarctic islands can live in subzero temperatures without freezing, whereas those on the mainland can survive being
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