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The blue whale is the largest of all whales and is said to be the largest animal in Earths history. The average length of an adult blue whale is 79 to 88 feet and the average weight is 130 to 150 tons. Blue whales are blue to blue-gray and may sometimes appear to have a faint yellow skin color because of the many microorganisms that accumulate on their bodies as they travel through colder waters. Blue whales prefer cold waters and open seas and prefer not to venture near coastal areas. However,
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  The blue whale is the largest of all whales and is said to be the largest animal in Earths history. Theaverage length of an adult blue whale is 79 to 88 feet and the average weight is 130 to 150 tons. Bluewhales are blue to blue-gray and may sometimes appear to have a faint yellow skin color because of themany microorganisms that accumulate on their bodies as they travel through colder waters. Blue whalesprefer cold waters and open seas and prefer not to venture near coastal areas. However, some whaleshave been seen off the coast of Peru.The blue whale eats mostly krill (small shrimp-like crustaceans) by using its baleen plates lining its mouthto sieve krill from the water. It can consume several tons of krill daily. Researchers have believed that theblue whale only eats in the summer, seldom eating during the rest of the year. But recent research hassuggested that some blue whales of the north may eat year-round and that blue whales found travelingwith empty stomachs may stop eating during migration and resume feeding at wintering areas. Bluewhales only mate in warmer waters and the gestation period lasts 10 to 11 months. The females givebirth to only one calf in the spring which gives the calf the entire summer to grow a layer of blubberneeded to protect it when traveling through colder waters. The calves nurse for around seven months.There are three subspecies of blue whales. The blue whales of the northern and southern hemispheresgenerally come together for mating, but they are considered two separate subspecies, Balaenoptera musculus musculus  and Balaenoptera musculus intermedia  . The third subspecies, the pygmy blue whale( Balaenoptera musculus brevicauda  ), is smaller than the others, and it is found in the sub-Antarcticwaters of the Indian Ocean and the southeast Atlantic Ocean. Over 350,000 whales have been huntedand killed, and by the 1960s, blue whales were on the edge of extinction. There are probably only around2500 blue whales left in the oceans and they are now legally protected despite opposition by the whalingindustry. Area(s) Where Listed As Endangered:  Central America, North America (including United States), Oceanic, South AmericaThe rainbow parrotfish is a large fish found in the western Atlantic ocean, from Florida, Bermuda and theBahamas to Argentina. Males grow up to 3.94 feet long. As their name suggests, rainbow parrotfish areattractively colored with deep green bodies, orange fins, and streaks of green extending outward towardthe back and tail. Males are more brightly colored than females but only when fully grown. Because oftheir unusual mouthparts, they are called parrotfish. The teeth are fused, forming a tough parrot-like beak.The beak is used to scrape algae and other organic matter from the surface of coral.Rainbow parrotfish can be found on coral reefs as deep as 25 meters, and at night they hide in crevices.They are very social and have been observed in schools of around 40 individuals. The schools graze overthe reef much like a herd of cattle over a grassy field. Large amount of calcareous materials areconsumed by the schools, and in just one year, one parrotfish can convert a ton of coral into sand. Oneadult male (called the supermale ) often leads these schools. Parrotfish are able to change sex. That isfemales if needed may become males in order to reproduce. The supermales are typically sex-reversedfemales and are strongly territorial, habitually driving other males from their areas. Juveniles have beenobserved in mangroves adjacent to the reef. These mangroves act as important nursery areas and alsoprovide food-rich, predator free safe-havens for the growing young.This creature is considered vulnerable due to loss of its mangrove nursery habitat. Since the young  parrotfish depend on the nurseries, removal of the mangroves has resulted in decline. Other threatsinclude pollution, over-fishing, and coastal development. To preserve the species, a number of reef havebeen established as reserves (where fishing and other human pressures are prevented) Pollution Everyone has heard of the ozone layer and the ozone hole  that allowstoo much harmful ultra violet light to get through the earth's atmosphereover the south pole during the Austral spring. This is caused by thepumping into the atmosphere of chlorofluorocarbons (CFCs) by theindustrialized world over a long time period.   The ozone hole is the best known example of pollutants that are producedin one place, but have their effects in another. As Antarctica is one of thecleanest, least polluted places on earth it is an ideal location for measuring the spread of globalpollutants. Minute traces of man-made chemicals used in other parts of the world can be detected in thesnow that falls over the region. They become concentrated in the bodies of local wildlife such as sealsand penguins.   More mundane, but equally great threats to Antarctica are the effects of casual pollution that goes alongwith every day life and activities. In a cold and slowly changing environment the effects of simple eventscan be there for years. Organic material for instance can take decades to decay where it would be gonein months even in the temperate parts of the world. The outline of footprints on a moss-bank can still beseen years later for instance.   Oil spills Oil spills are an increasing form of pollution in Antarctica as a result of increasing shipping activity in theregion. While ships often have facilities to contain waste oil and separate oil from water which is thentaken out of Antarctica for disposal, an ever greater presence is bound to lead to more accidents whichdo happen. In recent years there have been a number of groundings of tourist ships in shallow, poorlychartered waters and also accidents involving fishing boats in pursuit of the Patagonian toothfish.   Flotsam    Fur seals entangled in discarded rubbish Use of pictures by permission Rodrigo Hucke-Gaete, Instituto de Ecologie y Evolucion,Universidad Austral de Chile   An increasing problem in Antarctic waters (and in the rest of the world too) is flotsam and debris lostoverboard from ships, particularly fishing ships. Bits of fishing net, fishing line, boxes, strapping bandsetc. might sound harmless if unsightly, but they can have a deadly effect on wildlife.   Birds and seals get tangled up up lines and net. Fur seals can suffer the most as the youngsters inparticular are very playful and what starts off as a game with a plastic band can soon turn nasty as it getsstuck over the seals head. Unable to remove the band it begins to cut into the flesh causing physicalinjury, infection and ultimately a long and slow death.  
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