Wildlife of Antarctica

The wildlife of Antarctica are special animals and plants that have learned to live in one of the harshest places on Earth. They have adapted to the dryness, cold temperatures, and strong winds found in Antarctica. While the interior is extremely cold, the Antarctic Peninsula and the subantarctic islands are a bit warmer and have more water, making them easier places for life to survive.

The ocean around Antarctica is home to many amazing creatures. Eight species of penguins live here, along with several types of seals known as pinnipeds. The Southern Ocean also has many whales, including ten different kinds of cetaceans, many of which travel long distances to reach these waters. Tiny creatures called Antarctic krill form huge groups in the summer, providing food for many larger animals.

Though there are not many land animals in Antarctica, the ocean and nearby islands support a rich variety of life. Over 1,000 types of fungi have been found, mostly around the coast and islands. Plants are also mostly found on the subantarctic islands and parts of the Peninsula, with some mosses and lichens surviving even in the dry interior. Algae, including tiny plants called phytoplankton, are common in the surrounding waters and form the base of many food chains.

Unfortunately, human actions have brought new challenges for Antarctica's wildlife. Some outside species have arrived and threaten the native animals. In the past, overfishing and hunting have reduced the numbers of many animals. Today, pollution, habitat destruction, and changes in the climate are big worries. The Antarctic Treaty System works to protect this special place for science and to control how people use the land and sea around Antarctica.

Environmental conditions

See also: Antarctic realm and Climate of Antarctica

Most of Antarctica is covered in thick ice, making it one of the driest and coldest places on Earth. The interior has very low temperatures, lots of sunlight, and almost no rain or snow except near the coast. The coldest temperature ever recorded was very cold indeed!

The western part of the Antarctic Peninsula and the nearby subantarctic islands are warmer and wetter than the rest of the continent. Some parts of the peninsula can even get above freezing in the summer. These areas are friendlier for plants and animals because they have more water and milder temperatures.

The ocean around Antarctica stays pretty cold, between 1 °C and 2 °C all year. In the summer, a huge amount of sea ice covers the water. The seafloor near the coast is shallow, but it drops off quickly into very deep ocean areas. Most of the seafloor is made of soft materials like sand, mud, and gravel.

Animals

Many sea creatures live in Antarctica and the Arctic, ranging from whales and birds to tiny snails and worms. Big animals often travel between these areas, while smaller ones may spread through ocean currents. Even animals thought to be the same in both places often have small differences that make them unique to each region. Antarctic animals have special ways to stay warm, like thick coats and layers of fat in some mammals.

Antarctica's cold, dry lands have fewer animals than warmer places. Only a few birds and some introduced animals like rats and mice live on land there. The ocean around Antarctica is full of life, with up to 155,000 animals in just one square meter of seafloor. Many sea animals grow larger in the cold, oxygen-rich waters.

Birds

See also: List of birds of Antarctica

The rocky shores of Antarctica and nearby islands are home to over 100 million birds each spring. These include albatrosses, petrels, skuas, gulls, and terns. Penguins, especially emperor penguins, are most common in Antarctica. They have special feathers and body systems to stay warm and are the only penguins that breed during the winter.

Fish

There are not many fish species in the Southern Ocean, but some families, like snailfish and icefish, are very common. Icefish have special proteins in their blood that let them live in very cold water. The Antarctic toothfish and Patagonian toothfish are two of the largest fish there. Some icefish, like the Antarctic silverfish, live far from the shore.

Mammals

See also: List of mammals of Antarctica

Several seal species live in Antarctica, with the southern elephant seal being the largest. These seals breed on beaches or sea ice. Whales, including the huge blue whale, also visit Antarctic waters, though many travel to warmer areas in winter. Orcas stay in Antarctic waters year-round.

Land invertebrates

Most land animals in Antarctica are tiny insects and other small creatures, mostly found on nearby islands. The mainland has very few, like a small wingless midge. These animals can survive freezing temperatures in different ways.

Marine invertebrates

Arthropods

Five kinds of krill live in the Southern Ocean. Antarctic krill are extremely numerous, and many bigger animals depend on them for food. Some large sea creatures, like certain crabs and sea spiders, also live there.

Mollusks

Many sea creatures with shells live in Antarctic waters. These include different types of clams and squids, like the very large colossal squid.

Other marine invertebrates

Antarctic waters have many other sea animals, like sea urchins, brittle stars, and sea worms. Some of these, like certain sponges, can live for thousands of years. Jellyfish are also found there, including some very large ones.

Fungi

Fungal diversity in Antarctica is lower than in other parts of the world. About 1150 fungi species have been identified, including 400 lichens and 750 non-lichenized fungi. Only about 20 of these fungi are large enough to see without a microscope.

Lichens in Antarctica are plants and fungi that live together. There are around 400 different kinds of lichens, and they come in three main types: crusty lichens that form thin layers, leaf-like lichens, and shrub-like lichens. These lichens are very tough and can survive in harsh conditions, growing slowly—sometimes only a centimeter every hundred years.

Plants

Main article: Antarctic flora

Plants in Antarctica are mostly found on the western edge of the Antarctic Peninsula, where conditions are a bit warmer. Some coastal areas can have green, foamy plant blooms that cover large spaces. Mosses and lichens grow on rocks all over the continent. The islands near Antarctica are better places for plants to grow than the mainland itself. Human activities, like old whaling and sealing, have brought new plant types to these islands.

Some special places where steam and heat come out of the ground, called fumaroles, give plants a warmer spot to live. These spots melt snow and ice, creating tiny pools of water. Two big mountains in Antarctica, Mount Erebus and Mount Melbourne, each have such warm spots. There are also warm spots on some nearby islands.

Antarctica has about 100 kinds of mosses and around 25 kinds of liverworts. These plants can survive being frozen and dried out for many months, then come back to life when the sun shines. They usually grow without flowers or seeds, making new plants in other ways. Only two kinds of flowering plants live in Antarctica: Antarctic hair grass and Antarctic pearlwort. These tiny plants grow only on the western edge of the Antarctic Peninsula and a few close islands. On other islands near Antarctica, taller plants like tussock grass can grow.

Mosses

The moss species Campylopus pyriformis is found only where the ground is warm from heat deep inside the earth.

Moss species identified in recent research:

• Anomobryum subrotundifolium
• Bryoerythrophyllum recurvirostre
• Bryum anomobryum
• Bryum pseudotriquetrum
• Campylopus pyriformis
• Cephaloziella varians
• Ceratodon purpureus
• Didymodon brachyphyllus
• Grimmia plagiopodia
• Hennediella heimii
• Pohlia nutans
• Sarconeurum glaciale
• Schistidium antarctici (form. Grimmia antarctici)
• Syntrichia princeps

Others

See also: Antarctic microorganism

Bacteria have been brought back to life from Antarctic snow that is hundreds of years old. They have also been found deep under the ice in Lake Whillans, part of a group of subglacial lakes that never see sunlight.

Many types of algae live in Antarctica, often forming the start of food chains. About 400 kinds of tiny plants called phytoplankton float in the water of the Southern Ocean. These tiny plants grow a lot each year in spring and summer when days get longer and the ice melts, then shrink back in winter.

Algae also live on or under the sea ice, or on the seabed in shallow areas. Over 700 types of seaweed have been found, and many grow only in Antarctica. On land, algae can be found in fresh water and even in soil. Some snow algae can make snow look red, green, orange, or gray in summer, with up to about 10⁶ cells in every drop of water. The most common snow algae belong to a group called chlamydomonas, a type of green algae.

The biggest seaweeds are kelp species, like bull kelp (Durvillaea antarctica), which can grow longer than 20 metres (66 feet). As many as 47 kelp plants can live in just one square metre (10.8 square feet), growing up to 60 centimetres (24 inches) in a single day. When kelp breaks off, it becomes food for many animals and helps them travel across the Southern Ocean by floating.

Conservation

See also: Agreed Measures for the Conservation of Antarctic Fauna and Flora, Antarctic Specially Protected Area, and Antarctic Specially Managed Area

People can harm animals in Antarctica in many ways, such as making their homes dirty or taking away their food. Changes in the weather also make life harder for these animals.

Some animals that are not from Antarctica have come to live there, and they can hurt the animals that already live there. Some fish, like krill and toothfish, are caught too often, which can make it hard for them to survive. There are rules to help protect these animals and their homes. Countries that care for nearby islands have their own rules to keep these places safe, and some of these islands are very important and protected by special groups. The Antarctic Treaty helps make sure that everyone treats Antarctica like a special place for science and nature.