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The Clownfish, or Anemonefish, are the subfamily Amphiprioninae of the family Pomacentridae. There are currently 27 species, of which one is in the genus premnas and the rest are in the subfamily's type genus Amphiprion. The other pomacentrids are called damselfish.

Clownfish are native to wide ranges of the warm waters of the Pacific; some species ranges overlap others. Clownfish are not found in the Atlantic Ocean. Clownfish live in a mutual relationship with sea anemones, or in some case settle in some varieties of soft corals, or large polyp stony corals. Once an anemone or coral has been adopted, the clownfish will defend it vigorously.

However, clownfish in an aquarium environment can exist very well without an anemone (this may be advisable as most anemones are extremely difficult to keep alive even for experienced aquarists). The anemone is required in nature because reef life is dangerous for small, brightly coloured fish with very poor swimming abilities; in an aquarium lacking predators it is not needed. For this reason, clownfish never stray far from their host. In an aquarium, where they don't have to forage for food, it is very common for clownfish to remain within 6–12 inches of their host for an entire lifetime.

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The Emperor Penguin (Aptenodytes forsteri), at 1.3 metres (3 ft 9 in) tall and 32 kilograms in mass, is the tallest and heaviest of all penguins. It is the only penguin that breeds during the winter in Antarctica. Emperor Penguins eat mainly crustaceans (such as krill) but also occasionally indulge in small fish and squid. In the wild, Emperor Penguins typically live for 20 years, but some records indicate a maximum lifespan of around 40 years. The Emperor Penguin should not be confused with the King Penguin or the Royal Penguin.

Adults average about 1.3 metres (3 ft 9 in) and weigh 30 kilograms (75 lb) or more. The head and wings are black, the abdomen white, back bluish grey, and the bill is purplish pink. On the sides of the neck, there are two golden circular stripes.

Like the King Penguin counterpart, a male Emperor Penguin has an abdominal fold, the "brood pouch", between its legs and lower abdomen.

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Giant squid, once believed to be mythical creatures, are squid of the Architeuthidae family, represented by as many as eight species of the genus Architeuthis. They are deep-ocean dwelling animals that can grow to a tremendous size: recent estimates put the maximum size at 10 meters (34 ft) for males and 13 meters (44 ft) for females from caudal fin to the tip of the two long tentacles (second only to the Colossal Squid at an estimated 14 meters (46 ft), one of the largest living organisms).

The mantle length, though, is only about 2 meters (7 ft) in length (more for females, less for males), and the length of the squid excluding its tentacles is about 5 meters (16 ft). There were reported claims of specimens of up to 20 meters (66 ft), but none had been scientifically documented.

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The Antarctic krill, Euphausia superba, is a species of krill found in the Antarctic waters of the Southern Ocean. Antarctic krill are shrimp-like invertebrates that live in large schools, called swarms, sometimes reaching densities of 10,000 - 30,000 individual animals per cubic meter. They feed directly on minute phytoplankton, thereby using the primary production energy that the phytoplankton originally derived from the sun in order to sustain their pelagic (open ocean) life cycle. They grow to a length of 6 cm, weigh up to 2 grams, and can live for up to six years. They are a key species in the Antarctic ecosystem and are, in terms of biomass, likely the most successful animal species on the planet (approximately 500 million tonnes).

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Albatrosses, of the biological family Diomedeidae, are large seabirds allied to the procellariids, storm-petrels and diving-petrels in the order Procellariiformes (the tubenoses). They range widely in the Southern Ocean and the North Pacific. They are absent from the North Atlantic, although fossil remains show they once occurred there too. Albatrosses are amongst the largest of flying birds, and the great albatrosses (genus Diomedea) have the largest wingspans of any extant birds. The albatrosses are usually regarded as falling into four genera, but there is disagreement over the number of species.

Albatrosses are highly efficient in the air, using dynamic soaring and slope soaring to cover great distances with little exertion. They feed on squid, fish and krill by either scavenging, surface seizing or diving. Albatrosses are colonial, nesting for the most part on remote oceanic islands, often with several species nesting together. Pair bonds between males and females form over several years, with the use of ritualised dances, and will last for the life of the pair. A breeding season can take over a year from laying to fledging, with a single egg laid in each breeding attempt.

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Carcinus maenas is a common littoral crab, and an important invasive species. It is listed among the 100 "world's worst invasive alien species".

C. maenas is known by different names around the world. In the British Isles, it is generally referred to simply as the shore crab. In North America and South Africa, it bears the name green crab or European green crab. In Australia and New Zealand, it is referred to as either the European green crab or European shore crab.

C. maenas has a carapace up to 60 mm long and 90 mm wide, with five short teeth along the rim behind each eye, and three undulations between the eyes. The undulations, which do not protrude beyond the eyes are the simplest means of distinguishing C. maenas from the closely-related C. aestuarii, which can also be an invasive species. In C. aestuarii, the carapace lacks any bumps and extends forward beyond the eyes. The other character for distinguishing the two species is the form of the first and second pleopods (collectively the gonopods), which are straight and parallel in C. aestuarii, but curve outwards in C. maenas .

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A shrimp farm is an aquaculture business for the cultivation of marine shrimp or prawns for human consumption. Commercial shrimp farming began in the 1970s, and production grew steeply, particularly to match the market demands of the USA, Japan and Western Europe. The total global production of farmed shrimp reached more than 1.6 million tonnes in 2003, representing a value of nearly 9,000 million U.S. dollars. About 75% of farmed shrimp is produced in Asia, in particular in China and Thailand. The other 25% is produced mainly in Latin America, where Brazil is the largest producer. The largest exporting nation is Thailand.

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The oceanic whitetip shark, Carcharhinus longimanus, is a large pelagic shark of tropical and warm temperate seas. It is a stocky shark, most notable for its long, white tipped rounded fins.

This aggressive but slow-moving fish dominates feeding frenzies, and has attacked more humans than all other shark species combined — it is a notable danger to survivors of oceanic ship wrecks and downed aircraft. Recent studies have shown that its numbers are in steep decline — its large fins are highly valued as the chief ingredient of shark-fin soup and, as with other shark species, the oceanic whitetip faces mounting pressure from fishing throughout its range.

The oceanic whitetip shark was first described by naturalist Rene Primevere Lesson in his account of observations made during Louis Duperrey's 1822–1825 circumnavigation of the world on the corvette Coquille. Lesson described two specimens found in the Tuamotu Archipelago in French Polynesia, and named the shark Squalus maou after a Polynesian word for "shark". However, Lesson's description and name were forgotten.

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