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In contrast to the sparsely vegetated, barren, and ice-covered continent, the oceans surrounding Antarctica support a wealth of plant and invertebrate animal life.

The Southern Ocean's very cold water allows more oxygen to dissolve in the sea, which is advantageous for marine life.

Aquatic Fauna

The Patagonian Toothfish

The Patagonian Toothfish is a fish that roams the

islands of sub antartica. This fish is very high in mercury and is on the "Eco-Worst" list. One website I found recommended eating farm stripped bass or sablefish

insted of the Patafonian toothfish. The site also suggested on ly eating 1 meal of the patagonian toothfish per month. You would think that if this fish is so bad for your heath, then people found stop catching this type of fish. WRONG. The Patagonian Toothfish is still threatend by illegal pirate fishing spurred on by inernational demand

The Blue Whale

The Blue Whale is one of the many animals in the Antarctic that are in danger. The most recent surveys

(midpoint 1998) provided an estimate o of 2,280 blue whales in the Antarctic. The Blue Whale is still threatened by whalers,

even thought whaling was

banned in 1966 by the

International Whaling

Commission. As shown in the

graph above, before whaling

began the were 275,000 blue whales. Now there are only around 15,000 blue whales today. On a scale of 1 to 7 (7 being least concern, 1 being extinct),the blue whale is 4. Aside from hunting, bluse whales also have another enemy. Boats. After slamming into a boat or being caught in a fishing net, Blue Whales might die of their injuries. Since Blue Whales are massive, they din’t have any predators. This means there is only one species we can blame…us.

Aquatic Flora

WORDLE TIME-BY GWEN

http://www.wordle.net/show/wrdl/3456104/A

There are more diverse plants in the ocean than there are on land. (More aquatic then terrestial.) Most of plant biomass is found in marine habitats.

Kelps are the largest of the marine plants occurring in Antarctic and sub-Antarctic waters. Although kelps are important contributors to some Antarctic bottom communities, it is in subantarctic latitudes that they dominate.

Two main species occur at Macquarie Island, the leathery Bull Kelp Durvillaea antarctica which occupies the bottom of the rocky shore, and the Giant Kelp Macrocystis pyrifera which forms dense forests at depths greater than 6 m. Both species can reach lengths of over 20 m. At Heard Island, which lies below the Antarctic Convergence, and thus experiences much lower water temperatures, only Bull Kelp is present. In the kelp zone at Heard Island, one square metre of rocky shore may support up to 47 kelp plants, and over 200 kg of plant tissue. The Bull Kelp Durvillaea antarctica is thought to be the strongest kelp in the world and is able to withstand the massive seas that are characteristic of the Southern Ocean.

Kelp has one of the fastest growth rates of any of the marine plants (up to 60 cm per day or 3 kg of dry weight per square metre of habitat per day recorded for the Giant Kelp) and this makes it an important primary producer supplying food into nearshore and intertidal marine habitats.

Studies of the kelp holdfast communities at Macquarie Island and Heard Island have revealed that they support a higher diversity than any other shore habitat with over 90 species of invertebrate finding shelter in the tunnels and chambers that riddle their large masses.

Amphipod- a creture living in Bull Kelp

Algae are an extremely diverse group of aquatic plants. They range in size from single cells around a micrometre (1/1000 millimetre) in diameter to seaweeds the size of trees. Like other plants, they use the energy of sunlight to convert carbon dioxide and water into sugars and oxygen. Algae occur widely in Antarctica.

By far the most important are the marine phytoplankton - microscopic floating single cells. The 350 or so different species identified from Antarctic waters exhibit a huge diversity of size, shape, lifestyle, and food value to grazers. In addition to being the base of the food web on which essentially all other marine organisms depend, phytoplankton play a significant role in influencing global climate.

The Southern Ocean absorbs atmospheric carbon dioxide, the principal greenhouse gas. This is largely due to the uptake of carbon dioxide by phytoplankton. In addition, some produce sulphur-containing compounds which when released to the atmosphere form aerosol particles that promote the formation of clouds. Clouds are important in climate control because they reflect much of the Sun's energy back into space. Thus phytoplankton can influence regional climate.

As well as the phytoplankton, the sea-ice around Antarctica often has rich growths of algae, often on the underside. Some 700 seaweeds have been reported from the Southern Ocean of which some 35% are found no where else. In addition to seaweeds, the sea floor in shallow waters is covered with single-celled algae which provide food for bottom-dwelling animals.

On the Antarctic continent and subantarctic islands, algae live in lakes and streams, on moist soil and in snow banks. Some algae also live in the spaces between the grains of porous sandstone rocks and underneath translucent quartz rocks where moisture and light are available for their growth. Soil algae, together with their associated bacteria, are ecologically important as they contribute to the organic material and help bind the soil particles together with the mucilage and slime they secrete.

There are currently some 700 recorded species of terrestrial and aquatic algae in Antarctica. They have been collected from as far south as 86° 29'.

Microscopic algae are also found in snow and ice on land in the coastal regions. In summer the algae accumulate in sufficient numbers to colour the snow banks red, green, orange and even grey. Snow algae are generally single-celled organisms, although some multicellular and filamentous forms exist.

Snow algae grow in semi-permanent to permanent snow or ice in the alpine or polar regions of the world. These algae have successfully adapted to their harsh environment through the development of a number of features which include pigments, polyols (sugar alcohols, e.g. glycerine), sugars and lipids (oils), mucilage sheaths, motile stages and spore formation.

Snow algae, in adapting to an extreme environment, may have developed compounds (such as sunscreens and low temperature enzymes) and genes of commercial value.

The buoyancy of Bull Kelp is such that it can carry boulders weighing as much as 75 kg from the lower to the upper shore

Snow Algae/Sea Algae

Examples of Antarctic phytoplankton. Each cell is less than 0.2mm in size

Microscopic Image Of Snow Algae

RESOURCES

http://www.edf.org/page.cfm?tagID=15725

http://www.coolantarctica.com/Antarcticafactfile/endangered_antarctic_animals.htm\

http://en.wikipedia.org/wiki/Blue_whale - Threats_other_than_hunting

http://www.buzzle.com/articles/why-are-blue-whales-endangered.html

http://en.wikipedia.org/wiki/Chilean_sea_bass

http://www.antarcticconnection.com/antarctic/science/marinelife.shtml

http://www.antarctica.gov.au/about-antarctica/fact-files/plants

Gwen Mila Emily

Aquatic Flora and Fauna

This, along with the up- welling of currents which bring nutrients from the seabed to feed microscopic algae at the surface, is the key factor of all life in the Southern Ocean.

In this marine food chain, the microscopic algae (or plankton) provide food for krill, which in turn are eaten by fish, whales, seals and birds.

The food web in the Southern Ocean remains remarkably simple when compared with other oceans.

The cold waters are about four times as productive, acre for acre, as the other oceans of the world. The first link in this immense food chain is the microscopic algae which drift in the ocean and are eaten by zooplankton, of which krill is the most prominent, as well as being the principal food supply for whales.

Snow algae grow in semi-permanent to permanent snow or ice in the alpine or polar regions of the world. Their optimum growth temperatures are generally below 10° C. These algae have successfully adapted to their harsh environment through the development of a number of features which include pigments, polyols (sugar alcohols, e.g. glycerine), sugars and lipids (oils), mucilage sheaths, motile stages and spore formation. Large blooms in the summer months can reach cell concentrations of 105 to 106 cells per mL. and colour whole snowbanks red, orange, green or grey depending on the species and habitat conditions.

The snow algal flora is thought to be dominated by chlamydomonads, a group of green algae characterised by single cells with two flagella at their anterior ends. However, species from other algal groups are also important and the dominant alga in many of the glaciers around the world is a saccoderm desmid Mesotaenium berggrenii, an alga that colours the snow grey.

Many of the snow algal species go through a complicated life cycle involving vegetative and or motile cells which are usually green in colour and immotile spores or cysts which may be red, orange or yellow green in colour. The green vegetative cells give rise to green snow and the red and orange snow are generally caused by the spore stages of the snow algae although some snow algae may be red-pigmented in their vegetative state. These pigments protect the cells from high light and UV radiation damage during the summer months. The pigments may take the form of iron tannin compounds, as in M. berggrenii, or orange to red-pigmented lipids as in the majority of the snow algae.

The spores usually have thick walls and large amounts of lipid reserves, polyols and sugars. These spores are able to withstand sub-zero temperatures in winter and also high soil temperatures and desiccation in summer which would kill normal vegetative cells.

The motile stages enable them to re-colonise the snow from germinating spores left behind on the soil as well as to position themselves at the optimum depth for photosynthesis in the snow/ice column.

The cells of some species also secrete copious amounts of mucilage which enable them to adhere to one another and to snow crystals and prevent the cellls from being washed away by meltwater. The mucilage also forms a protective coat and delays desiccation. It may have an additional function as an UV shield.

Snow algae were probably derived from species of soil or aquatic algae. Their distribution is governed by factors such as nutrients, pH, salinity, aspect and sunlight.

Snow algae, in adapting to an extreme environment, may have developed compounds (such as sunscreens and low temperature enzymes) and genes of commercial value.

A few species are common worldwide, but others are restricted to either the Northern or Southern Hemispheres.

Kelps are the largest of the marine plants occurring in Antarctic and sub-Antarctic waters. Although kelps are important contributors to some Antarctic bottom communities, it is in subantarctic latitudes that they dominate.

Two main species occur at Macquarie Island, the leathery Bull Kelp Durvillaea antarctica which occupies the bottom of the rocky shore, and the Giant Kelp Macrocystis pyrifera which forms dense forests at depths greater than 6 m. Both species can reach lengths of over 20 m. At Heard Island, which lies below the Antarctic Convergence, and thus experiences much lower water temperatures, only Bull Kelp is present. In the kelp zone at Heard Island, one square metre of rocky shore may support up to 47 kelp plants, and over 200 kg of plant tissue. The Bull Kelp Durvillaea antarctica is thought to be the strongest kelp in the world and is able to withstand the massive seas that are characteristic of the Southern Ocean.

Kelp has one of the fastest growth rates of any of the marine plants (up to 60 cm per day or 3 kg of dry weight per square metre of habitat per day recorded for the Giant Kelp) and this makes it an important primary producer supplying food into nearshore and intertidal marine habitats. Some animals, such as sea-urchins, shells and small crustaceans, feed directly on kelp. However, it is through the breakdown of detached pieces of kelp and whole plants that most consumers benefit. Although kelp plants have a strong "root" system, known as a holdfast, that attaches them to the substrate, wave strength in the Southern Ocean is such that plants are often torn from the bottom and flung onto adjacent beaches. Smaller pieces of kelp also break off during heavy seas and these may strand on local beaches or sink into deeper waters. Wherever they end up, detached kelp becomes a food source for scavenging animals such as amphipods (beach hoppers) and are gradually broken down liberating nutrients back into coastal waters. As well as providing an important supply of food to local marine communities, kelp provides a refuge from the harsh physical environment for many organisms. The long fronds of Bull Kelp, that are often packed tightly around the lower shore, absorb much of the energy from the waves crashing on the coast, creating a lower energy environment where marine life abounds. Small plants and animals can be found living between the large holdfasts of kelp and many animals also live within the holdfast itself.

Despite the fact that the holdfast of the Bull Kelp is a solid hemisphere of tough tissue, a species of small isopod crustacean (Limnoria) makes its living consuming this tissue. In the process, the holdfast becomes riddled with tunnels and chambers which are used as living space by other small invertebrates. Different species of Limnoria are the primary space providers at Macquarie Island (L. stephenseni) and Heard Island (L. antarctica).

Studies of the kelp holdfast communities at Macquarie Island and Heard Island have revealed that they support a higher diversity than any other shore habitat with over 90 species of invertebrate finding shelter in the tunnels and chambers that riddle their large masses. A typical holdfast community includes worms of many varieties, molluscs, mites, sea-stars, sea-cucumbers and a large variety of crustaceans.

The diversity of organisms inhabiting the holdfast makes this habitat a valuable tool for monitoring changes in shore communities under the influence of both natural, and human induced impacts. Indeed, the holdfast community of Bull Kelp was the most sensitive indicator of the effects of, and subsequent recovery from, a small oil spill at Macquarie Island in 1987.

Both Bull Kelp and Giant Kelp have very buoyant fronds that are capable of supporting whole plants at sea for considerable periods of time. Bull Kelp, in particular, is exceptionally buoyant and has been documented to carry boulders weighing up to 75 kg from the lower to upper shore at Macquarie Island. It has been hypothesised that animals associated with floating kelp (kelp rafts) can be transported between the far-flung islands across the subantarctic. This potentially explains the observation that many kelp-associated species are found throughout the islands of the subantarctic.

There are plenty of rafts available to animals in the Southern Ocean with recent surveys estimating that, between the latitudes of 46-53°S, over 70 million plants are afloat at any one time. In addition, some recent studies have indicated that animals can live attached to floating kelp for long periods of time. This idea of invertebrate transport by kelp is the subject of continuing research.

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