Wild fisheries of the world

^[2]

Celebes Sea

The Celebes Sea has warm clear waters and harbors about 580 of the world's 793 species of reef-building corals, which grow as some of the most bio-diverse coral reefs in the world, and an impressive array of marine life, including whales and dolphins, sea turtles, manta rays, eagle rays, barracuda, marlin and other reef and pelagic species. Tuna and yellow fin tuna are also abundant. The sea also yields other aquatic products like sea tang.

A map of the Coral Sea Islands.

The Coral Sea is an ecologically important source of coral.^[12]

The East China Sea.

The Philippine Sea

The Philippine Sea.

The Sea of Japan. Like the Mediterranean Sea, it has almost no tides due to its nearly complete enclosure.^[13] It has an area of 978,000 square kilometre, a mean depth of 1,753 meters, and a maximum depth of 3,742 meters.

The areas in the north and the southeast are rich fishing grounds. The importance of the fishery in the sea is well illustrated by the dispute between South Korea and Japan over Liancourt Rocks.

The South China Sea is the repository of large sediment volumes delivered by the Mekong River, Red River and Pearl River. Within the sea, there are over 200 identified islands and reefs, including a 100 km wide seamount with a depth of 20 m and an area of 8,866 km². According to studies made by the Department of Environment and Natural Resources, Philippines, this body of water holds one third of the all world's marine biodiversity, thereby making it a very important area for the ecosystem.

The Sulu Sea.

Map of the Tasman Sea

The Tasman Sea features a number of coastal islands and mid-sea island groups.

The Yellow Sea

The Andaman Sea is a body of water to the southeast of the Bay of Bengal, south of Myanmar, west of Thailand and east of the Andaman Islands; it is part of the Indian Ocean. It is roughly 1,200 kilometres (750 mi) long (north-south) and 650 kilometres (400 mi) wide (east-west), with an area of 797,700 square kilometres (308,000 sq mi). Its average depth is 870 metres (2,854 ft), and the maximum depth is 3,777 metres (12,392 ft).

The Arabian Sea is a region of the Indian Ocean bounded on the east by India, on the north by Pakistan and Iran, on the west by Arabian Peninsula, on the south, approximately, by a line between Cape Guardafui, the north-east point of Somalia, Socotra and Kanyakumari (Cape Comorin) in India.

The maximum width of the Arabian Sea is approximately 2,400 km (1,490 mi), and its maximum depth is 4,652 metres (15,262 ft),

The Bay of Bengal occupies an area of 2,172,000 km². A number of large rivers – Ganges, Brahmaputra, Ayeyarwady, Godavari, Mahanadi, Krishna and Kaveri – flow into the Bay of Bengal. The islands in the bay are very numerous, including the Andaman, Nicobar and Mergui groups.

The Bay of Bengal is full of biological diversity, diverging amongst coral reefs, estuaries, fish spawning and nursery areas, and mangroves. The Bay of Bengal is one of the World's 64 largest marine ecosystems.

Kerilia jerdonii is a sea snake of the Bay of Bengal. Glory of Bengal Cone (Conus bengalensis) is just one of the seashells which can be photographed along beaches of the Bay of Bengal.^[25]

An endangered species, the Olive Ridley sea turtle can survive because of the nesting grounds made available at the Gahirmatha Marine Wildlife Sanctuary, Gahirmatha Beach, Orissa, India.

Bryde's Whale which can be seen in the Bay of Bengal is the 10th heaviest animal of the world, weighing in at 22,000 kg (48,000 lb).

Marlin, barracuda, skipjack tuna, (Katsuwonus pelamis), yellowfin tuna, Indo-Pacific humpbacked dolphin (Sousa chinensis) , and Bryde's whale (Balaenoptera edeni) are a few of the marine animals. Bay of Bengal Hogfish (Bodianus neilli) is a type of Wrass which live in turbid lagoon reefs or shallow coastal reefs. Schools of dolphins can be seen, whether they are the bottle nose dolphin (Tursiops truncatus), Pantropical spotted dolphin (Stenella attenuata) or the spinner dolphin (stenella longirostris) . Tuna and dolphins are usually residing in the same waters. In shallower and warmer coastal waters the Irrawaddy Dolphins (Orcaella brevirostris) can be found.^[26][27]

The Great Australian Bight is a large bight, or open bay located off the central and western portions of the southern coastline of mainland Australia.

The coast line of the Great Australian Bight is characterised by stunning cliff faces (up to 60 m high), surfing beaches and rock platforms, ideal for whale-watching. The waters of the Great Australian Bight, despite being relatively shallow, are not fertile. While most continental shelves are rich in sea life and make popular fishing areas, the barren deserts north of the bight have very little rainfall, and what there is mostly flows inland, to dissipate underground or in salt lakes. In consequence, the Great Australian Bight receives very little of the runoff that fertilises most continental shelves and is essentially a marine desert. It is probably best noted for the large number of sharks that frequent its coastal waters, as well as the increasing numbers of Southern Right Whales that migrate within the region.

Economically, the Bight has been exploited over many years as part of the fishing, whaling and shellfish industries. Bluefin tuna have been a favoured target of fishing in the Bight.

The Gulf of Aden. The temperature of the gulf varies between 15 °C (59 °F) and 28 °C (82 °F), depending on the season and the appearance of monsoons. The salinity of the Gulf at 10 metres (33 ft) depth varies from 35.3 ‰ along the eastern Somali coast to as high as 37.3 ‰ in the Gulf's center,^[28] while the oxygen content in the Gulf of Aden at the same depth is typically between 4.0 and 5.0 mL/L.^[29]

A geologically young body of water, the Gulf of Aden has a unique biodiversity that contains many varieties of fish, coral, seabirds, and invertebrates. This rich ecological diversity has benefitted from the relative lack of pollution during the history of human habitation around the Gulf, but environmental groups fear that the lack of a coordinated effort to control pollution may jeopardize the Gulf's ecosphere.^[30]

The Gulf of Aden is an area known for acts of piracy,^[31]|-

The Gulf of Oman is a gulf that connects the Arabian Sea with the Strait of Hormuz which then runs to the Persian Gulf.

The Mozambique Channel is a portion of the Indian Ocean between the island of Madagascar and southeast Africa, namely Mozambique. The channel is approximately 460 kilometers across at its narrowest point between Angoche, Mozambique, and Tambohorano, Madagascar. It reaches a depth of 3,292 meters about 230 kilometers off the coast of Mozambique. A warm current flows in a southward direction in the channel, leading into the Agulhas Current off the east coast of South Africa. It is 1600 kilometers long and its width varies from 400 to 950 kilometers.

The Persian Gulf is an extension of the Indian Ocean located between Iran and the Arabian Peninsula. The natural environment of the Persian Gulf is very rich with good fishing grounds, extensive coral reefs, and abundant pearl oysters, but its ecology has become increasingly under pressure from the heavy industrialisation and in particular the repeated major petroleum spillages associated with recent wars fought in the region.

The Red Sea occupies a part of the Great Rift Valley, and has a surface area of 438,000 km². It is 2250 km long and, at its widest point, 355 km wide. It has a maximum depth of 2211 m in the central median trench and an average depth of 490 m (1,608 feet ), but there are also extensive shallow shelves, noted for their marine life and corals. The sea is the habitat of over 1,000 invertebrate species and 200 soft and hard corals and is the world's most northern tropical sea.

The Red Sea is a rich and diverse ecosystem. More than 1100 species of fish^[32] have been recorded in the Red Sea, and around 10% of these are found nowhere else.^[33] This also includes around 75 species of deepwater fish.^[32] The rich diversity is in part due to the 2,000 km (1,240 mi) of coral reef extending along its coastline; these fringing reefs are 5000-7000 years old and are largely formed of stony acropora and porites corals. The reefs form platforms and sometimes lagoons along the coast and occasional other features such as cylinders (such as the blue hole at Dahab). These coastal reefs are also visited by pelagic species of red sea fish, including some of the 44 species of shark.

Approximately 40% of the Red Sea is quite shallow (under 100 m/330 ft), and about 25% is under 50 m (164 ft) deep. About 15% of the Red Sea is over 1,000 m (3,300 ft) depth that forms the deep axial trough. Shelf breaks are marked by coral reefs Continental slope has an irregular profile (series of steps down to ~500 m/1,640 ft)

The Amundsen Sea is an arm of the Southern Ocean off Marie Byrd Land in western Antarctica. It is mostly ice-covered, averaging about 3 km (2 miles) in thickness and roughly the size of Texas.

The Bellingshausen Sea is an area along the west side of the Antarctic Peninsula between Alexander Island and Thurston Island.

The Ross Sea is a deep bay of the Southern Ocean in Antarctica between Victoria Land and Marie Byrd Land. The southern part is covered by the Ross Ice Shelf. In the west of the Ross sea, McMurdo Sound is a port which is usually free of ice during the summer.

A 10 metre (32.8 feet) long colossal squid weighing 495 kilograms (1,091 lb) was captured in the Ross Sea on 22 February 2007.

The Ross Sea toothfish fishery

There are two main species of toothfish: the Patagonian toothfish, Dissostichus eleginoides, which occurs mainly in Subantarctic waters, and the [[Antarctic toothfish]], D. mawsoni, which is found only in Antarctic waters. The Antarctic toothfish is caught from the Polar Convergence (at about 60° S) south to the Antarctic continent, whereas the Patagonian toothfish is mainly caught north of 65° S. The Ross Sea region is unusual because between these latitudes both species are abundant and show considerable overlap in their distribution. Indeed, over 90% of the longlines set in the fishery in this area have both species on the same line. Both species are found down to depths of over 2000 m

The Ross Sea toothfish fishery is the southernmost fishery in the world. The extreme cold and ice conditions can make fishing both difficult and dangerous. During most of the year the Ross Sea itself is covered by ice. However, during January and February, areas of open water (called polynas) allow access to the continental shelf and slope. Longline vessels (predominantly from New Zealand, but also from South Africa, Russia, and Uruguay) have taken advantage of this to develop an exploratory fishery. They start working in the deep south, and as the season progresses they move north to stay ahead of the freezing sea ice, and by May are restricted to the northernmost fishing grounds. CCAMLR agrees on annual precautionary catch limits. Since 1998, the catch has steadily increased from about 40 t to over 1350 t in 2002 (all of these catches are well within the CCAMLR limits). Because it is a high latitude fishery, Antarctic toothfish has formed over 95% of the catch. Up to three New Zealand vessels have been involved in the fishery in any year. However, in the 2003 season up to six New Zealand vessels are fishing in these waters.^[34]

An aerial view of Antarctica. Weddell Sea is the 'bay' in the top left corner.

The Weddell Sea land boundaries are defined by the bay formed from the coasts of Coats Land and the Antarctic Peninsula. Much of the southern part of the sea, up to Elephant Island, is permanent ice, the Filchner-Ronne Ice Shelf. At its widest the sea is around 2,000 km across, in area it is around 2.8 million km². The ice shelves which used to extend roughly 3900 square miles (10,000 km²) over the Weddell Sea have completely disappeared by 2002.

Famous coral reefs and reef areas of the world include:

• The Great Barrier Reef - largest coral reef system in the world, Queensland, Australia;
• The Belize Barrier Reef - second largest in the world, stretching from southern Quintana Roo, Mexico and all along the coast of Belize down to the Bay Islands of Honduras.
• The Red Sea Coral Reef - located off the coast of Egypt and Saudi Arabia.
• Pulley Ridge - deepest photosynthetic coral reef, Florida
• Many of the numerous reefs found scattered over the Maldives
• The New Caledonia Barrier Reef - second longest double barrier reef in the world, with a length of about 1500km.

Coral reefs support an extraordinary biodiversity; although they are located in nutrient-poor tropical waters. The process of nutrient cycling between corals, zooxanthellae, and other reef organisms provides an explanation for why coral reefs flourish in these waters: recycling ensures that fewer nutrients are needed overall to support the community.

Coral reefs are home to a variety of tropical or reef fish, such as the colorful parrotfish, angelfish, damselfish and butterflyfish. Other fish groups found on coral reefs include groupers, snappers, grunts and wrasses. Over 4,000 species of fish inhabit coral reefs.^[39] It has been suggested that the high number of fish species that inhabit coral reefs are able to coexist in such high numbers because any free living space is rapidly inhabited by the first planktonic fish larvae that occupy it. These fish then inhabit the space for the rest of their life. The species that inhabit the free space is random and has therefore been termed 'a lottery for living space'.^[41]

Reefs are also home to a large variety of other organisms, including sponges, Cnidarians (which includes some types of corals and jellyfish), worms, crustaceans (including shrimp, spiny lobsters and crabs), molluscs (including cephalopods), echinoderms (including starfish, sea urchins and sea cucumbers), sea squirts, sea turtles and sea snakes.^[42][39]

Bioerosion (coral damage) such as this may be caused by coral bleaching.^[43]

Human activity may represent the greatest threat to coral reefs living in Earth's oceans. In particular, pollution and over-fishing are the most serious threats to these ecosystems. Physical destruction of reefs due to boat and shipping traffic is also a problem. The live food fish trade has been implicated as a driver of decline due to the use of cyanide and disaster for peoples living in the tropics. Hughes, et al, (2003), writes that "with increased human population and improved storage and transport systems, the scale of human impacts on reefs has grown exponentially. For example, markets for fishes and other natural resources have become global, supplying demand for reef resources far removed from their tropical sources."^[44]

Currently researchers are working to determine the degree various factors impact the reef systems. The list of factors is long but includes the oceans acting as a carbon dioxide sink, changes in Earth's atmosphere, ultraviolet light, ocean acidification, biological virus, impacts of dust storms carrying agents to far flung reef systems, various pollutants, impacts of algal blooms and others. Reefs are threatened well beyond coastal areas and so the problem is broader than factors from land development and pollution though those are too causing considerable damage.

Southeast Asian coral reefs are at risk from damaging fishing practices (such as cyanide and blast fishing), overfishing, sedimentation, pollution and bleaching. A variety of activities, including education, regulation, and the establishment of marine protected areas are under way to protect these reefs. Indonesia, for example has nearly 33,000 square miles (85,000 km²) of coral reefs. Its waters are home to a third of the world’s total corals and a quarter of its fish species. Indonesia's coral reefs are located in the heart of the Coral Triangle and have been victim to destructive fishing, unregulated tourism, and bleaching due to climatic changes. Data from 414 reef monitoring stations throughout Indonesia in 2000 found that only 6% of Indonesia’s coral reefs are in excellent condition, while 24% are in good condition, and approximately 70% are in poor to fair condition (2003 The Johns Hopkins University).

General estimates show approximately 10% of the coral reefs around the world are already dead.^[45][46]Problems range from environmental effects of fishing techniques, described above, to ocean acidification.^[47] Coral bleaching is another manifestation of the problem and is showing up in reefs across the planet.

NInhabitants of Ahus Island, Manus Province, Papua New Guinea, have followed a generations-old practice of restricting fishing in six areas of their reef lagoon. While line fishing is permitted, net and spear fishing are restricted based on cultural traditions. The result is that both the biomass and individual fish sizes are significantly larger in these areas than in places where fishing is completely unrestricted.^[48][49] It is estimated that about 60% of the world’s reefs are at risk due to destructive, human-related activities. The threat to the health of reefs is particularly strong in Southeast Asia, where an enormous 80% of reefs are considered endangered.

Organisations as Coral Cay, Counterpart ^[50] and the Foundation of the peoples of the South Pacific are currently undertaking coral reef/atoll restoration projects. They are doing so using simple methods of plant propagation. Other organisations as Practical Action have released informational documents on how to set-up coral reef restoration to the public.^[51]

In addition to simply providing physical presence in this zone, the seamount itself may deflect deep currents and create upwelling. This process can bring nutrients into the photosynthetic zone, producing an area of activity in an otherwise desert-like open ocean. Seamounts may thus be vital stopping points for some migratory animals such as whales. Some recent research indicates whales may use such features as navigational aids throughout their migration. Due to the larger populations of fish in these areas overexpoitation by the fishing industry has caused some seamount fauna populations to decrease considerably.

The primary productivity of the epipelagic waters above the submerged peak can often be enhanced by the hydrographic conditions of the seamount.^[53] This increases the densities of the zooplankton and leads to the high concentrations of fish in these areas. Another theory for this is that the fish are sustained on the diurnal migration of zooplankton being interrupted by the presence of the seamount, and causing the zooplankton to stay in the area. It is also possible that the high densities of fishes has more to do with the fish life histories and interaction with the benthic fauna of the seamount.^[54]

The benthic fauna of the seamounts is dominated by suspension feeders, including sponges and true corals. For some seamounts that peaks at 200-300 metres below the surface benthic macroalgae is common. The sedimentary infauna is dominated by polychaete worms.

For a long time it has been surmised that many pelagic animals visit seamounts to gather food, but proof this of this aggregating effect has been lacking. The first demonstration of this conjecture has recently been published ^[55]

During the 1960s, Russia, Australia and New Zealand started to look for new stocks of fish and began to trawl the seamounts. The majority of the invertebrates brought up are corals, and are mainly used for the jewelry trade. The two major fish species were the orange roughy (Hoplostethus atlanticus) and pelagic armourhead (Pseudopentaceros wheeleri), which were quickly overexploited due to lack of knowledge of the longevity of the fish, late maturity, low fecundity, small geographic range and recuitment to the fishery. As well as the fishes being overexploited the benthic communities were destroyed by the trawling gear.

• CenSeam, Census of Marine Life project CenSeam: a global census of marine life on seamounts