Wild fisheries of the world

	Email		Print
	Bookmark		Link

Wild fisheries of the world

A fishery

Fishery

Generally, a fishery is a unit, engaged in raising and/or harvesting fish, which is determined by an authority or other entity to be a fishery....
is an area with an associated fish

Fish

A fish is any marine biology vertebrate animal that is typically ectothermic , covered with scale , and equipped with two sets of paired fins and several unpaired fins....
or aquatic

Aquatic animal

An aquatic animal is an animal, either vertebrate or invertebrate, which lives in water for most or all of its life.Natural environments and the animals that live in them can be categorized as aquatic or terrestrial ecoregion ....
population which is harvested for its commercial value. Fisheries can be marine

Marine

Marine or Marines may refer to:*Marine , a general term for things relating to the sea or ocean*Marine , a member of the military in an infantry or amphibious force under the authority of a navy, or in several cases, of an independent amphibious forces ...
(saltwater) or freshwater

Freshwater

Freshwater is a word that refers to bodies of water such as ponds, lakes, rivers and streams containing low concentrations of dissolved salts and other total dissolved solids....
. They can also be wild or farmed. This article is an overview of the habitats occupied by the worlds' wild fisheries, and the human impacts on those habitats.

Wild fisheries are sometimes called capture fisheries. The aquatic life they support is not controlled and needs to be "captured" or fished

Fishing

Fishing is the activity of catching fish. Fishing techniques include Fish net, Fish trap, Spearfishing, angling and Gathering seafood by hand. The term fishing may be applied to catching other aquatic animals such as different types of shellfish, squid, octopus, turtles, Edible frog and some edible marine invertebrates....
.

Discussion

Ask a question about 'Wild fisheries of the world'

Start a new discussion about 'Wild fisheries of the world'

Answer questions from other users

Full Discussion Forum

Encyclopedia

A fishery

Fishery

Generally, a fishery is a unit, engaged in raising and/or harvesting fish, which is determined by an authority or other entity to be a fishery....
is an area with an associated fish

Fish

A fish is any marine biology vertebrate animal that is typically ectothermic , covered with scale , and equipped with two sets of paired fins and several unpaired fins....
or aquatic

Aquatic animal

Marine

Freshwater

Fishing

Coast

The coast is defined as that part of the land adjoining or near the ocean or its saltwater arms. A precise line that can be called a coastline cannot be determined due to the process of tides....
s and continental shelves. They also exist in lake

Lake

A lake is a terrain feature , a body of liquid on the surface of a world that is localized to the bottom of basin and moves slowly if it moves at all....
s and river

River

A river is a natural stream of water, usually freshwater, flowing toward an ocean, a lake, or another stream. In some cases a river flows into the ground or dries up completely before reaching another body of water....
s. Issues with wild fisheries are overfishing

Overfishing

Overfishing occurs when fishing activities reduce fish stocks below an acceptable level. This can occur in any body of water from a pond to the oceans....
and pollution

Marine pollution

Marine pollution occurs when harmful effects, or potentially harmful effects, can result from the entry into the ocean of chemicals, particle , industrial, agricultural and residential waste, or the spread of invasive organisms....
. Significant wild fisheries have collapsed or are in danger of collapsing, due to overfishing and pollution. Overall, production from the world's wild fisheries has levelled out, and may be starting to decline.

As a contrast to wild fisheries, farmed fisheries can operate in sheltered coastal waters, in rivers, lakes and pond

Pond

A pond is a body of water smaller than a lake, both being examples of terrain feature. Although the term pond is universally used to describe waterbodies that are smaller than lakes, an internationally recognised size cutoff has not yet been agreed, with values ranging from 2 hectares to 8 hectares used to distinguish the smaller from...
s, or in enclosed bodies of water such as tanks. Farmed fisheries are technological in nature, and revolve around developments in aquaculture

Aquaculture

Aquaculture is the farming of freshwater and saltwater organisms including molluscs, crustaceans and aquatic plants. Unlike fishing, aquaculture, also known as aquafarming, implies the cultivation of aquatic populations under controlled conditions....
. Farmed fisheries are expanding, and Chinese

China

China is a Culture of China, an ancient civilization, and, depending on perspective, a national or multinational entity extending over a large area in East Asia....
aquaculture in particular is making many advances.

Marine fisheries

Topography

The productivity of marine fisheries is largely determined by marine topography Topography Topography is the study of Earth's surface shape and features or those ofplanets, Natural satellite, and asteroids. It is also the description of such surface shapes and features .... , including its interaction with ocean current Ocean current An ocean current is continuous, directed movement of ocean water. The currents are generated from the forces acting upon the water like the Earth's rotation, the wind, the temperature, salinity differences and the tide.... s and the diminishment of sunlight with depth. Marine topography is defined by various coastal and oceanic landforms List of landforms Landforms are categorised by characteristic physical attributes such as elevation, slope, orientation, stratification, rock exposure, and soil type.... , ranging from coastal estuaries Estuary An estuary is a semi-enclosed coastal body of water with one or more rivers or streams flowing into it, and with a free connection to the open sea.... and shorelines; to continental shelves Continental shelf The continental shelf is the extended perimeter of each continent and associated coastal plain, and was part of the continent during the glacial periods, but is undersea during Ice age such as the current epoch by relatively shallow seas and Bay.... and coral reef Coral reef Coral reefs are aragonite structures produced by living organisms. In most reefs the predominant organisms are colonial cnidarian that secrete an exoskeleton of calcium carbonate.... s; to underwater and deep sea Deep sea File:Nur04506.jpgThe deep sea, or deep layer, is the lowest layer in the ocean, existing below the thermocline, at a depth of 1000 fathoms or more.... features such as ocean rises and seamount Seamount A seamount is a mountain rising from the ocean seafloor that does not reach to the water's surface , and thus is not an island. These are typically formed from extinct volcanoes, that rise abruptly and are usually found rising from a seafloor of 1,000?4,000 meters depth.... s.

Ocean currents

An ocean current Ocean current An ocean current is continuous, directed movement of ocean water. The currents are generated from the forces acting upon the water like the Earth's rotation, the wind, the temperature, salinity differences and the tide.... is continuous, directed movement of ocean water. Ocean currents are rivers of relatively warm or cold water within the ocean. The currents are generated from the forces acting upon the water like the planet rotation, the wind, the temperature Temperature In physics, temperature is a physical property of a Physical system that underlies the common notions of hot and cold; something that feels hotter generally has the greater temperature.... and salinity Salinity Salinity is the saltiness or dissolved salt content of a body of water. Salinity in Australian English and North American English may also refer to the salt in soil .... (hence isopycnal Isopycnal An isopycnal is a surface of constant potential density of water. In the ocean, as the depth increases, so too does the density. Varying degrees of salinity and temperature act to modify the density of water, and the denser water always lies below the less dense water.... ) differences and the gravitation of the moon Tide Tides are the rising of Earth's ocean surface caused by the tidal forces of the Moon and the Sun acting on the oceans. Tides cause changes in the depth of the marine and estuary water bodies and produce oscillating currents known as tidal streams, making prediction of tides important for coastal navigation .... . The depth contours, the shore Shore A shore or shoreline is the fringe of land at the edge of a large body of water, such as an ocean, sea, or lake.Shores are influenced by the topography of the surrounding landscape, as well as by water induced erosion, such as ocean surface wave.... line and other currents influence the current's direction and strength.

More on currents
circulation]] Ocean currents can flow for thousands of kilometers. Surface ocean currents are generally wind driven and develop their typical clockwise spirals in the northern hemisphere and counter-clockwise rotation in the southern hemisphere because of the imposed wind stresses. In wind driven currents, the Ekman spiral Ekman spiral The Ekman spiral refers to a structure of currents or winds near a horizontal boundary in which the flow direction rotates as one moves away from the boundary.... effect results in the currents flowing at an angle to the driving winds. The areas of surface ocean currents move somewhat with the season Season A season is one of the major divisions of the year, generally based on yearly periodic changes in weather.Seasons result from the yearly revolution of the Earth around the Sun and the Axial tilt.... s; this is most notable in equatorial currents. Deep ocean currents are driven by density and temperature gradients. Thermohaline circulation Thermohaline circulation The term thermohaline circulation refers to the part of the large-scale ocean circulation that is driven by global Density gradient created by surface heat and freshwater Flux.... , also known as the ocean's conveyor belt, refers to the deep ocean density-driven ocean basin currents. These currents, which flow under the surface of the ocean and are thus hidden from immediate detection, are called submarine rivers. Upwelling Upwelling An Upwelling is an physical oceanography phenomenon that involves wind-driven motion of dense, cooler, and usually nutrient-rich water towards the ocean surface, replacing the warmer, usually nutrient-depleted surface water.... and downwelling Downwelling Downwelling is the process of accumulation and sinking of higher density material beneath lower density material, such as cold or saline water beneath warmer or fresher water or cold air beneath warm air.... areas in the oceans are areas where significant vertical movement of ocean water is observed. Surface currents make up about 10% of all the water in the ocean. Surface currents are generally restricted to the upper 400 meters of the ocean. The movement of deep water in the ocean basins is by density driven forces and gravity. The density difference is a function of different temperatures and salinity. Deep waters sink into the deep ocean basins at high latitudes where the temperatures are cold enough to cause the density to increase. The main causes of currents are: solar heating, winds and gravity. Ocean currents are also very important in the dispersal of many life forms. A dramatic example is the life-cycle of the eel. Currents also determine the disposition of marine debris Marine debris Marine debris, also known as marine litter, is human-created waste that has deliberately or accidentally become afloat in a lake, sea, ocean or waterway.... .

Gyres and upwelling

Oceanic gyres are large-scale ocean currents caused by the Coriolis effect Coriolis effect In physics, the Coriolis effect is an apparent deflection of moving objects when they are viewed from a rotating reference frame.Newton's laws of motion govern the motion of an object in an inertial frame of reference.... . Wind-driven surface currents interact with these gyres and the underwater topography, such as seamounts and the edge of continental shelves, to produce downwellings and upwelling Upwelling An Upwelling is an physical oceanography phenomenon that involves wind-driven motion of dense, cooler, and usually nutrient-rich water towards the ocean surface, replacing the warmer, usually nutrient-depleted surface water.... s. These can transport nutrients and produce productive fishing grounds. Coastal upwelling supports some of the most productive fisheries in the world, like small pelagics (sardines, anchovies, etc.). Regions of upwelling include coastal Peru Peru Peru , officially the Republic of Peru , is a country in western South America. It is bordered on the north by Ecuador and Colombia, on the east by Brazil, on the southeast by Bolivia, on the south by Chile, and on the west by the Pacific Ocean.... , Chile Chile Chile, officially the Republic of Chile , is a country in South America occupying a long and narrow coastal strip wedged between the Andes mountains and the Pacific Ocean.... , Arabian Sea Arabian Sea 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, Kanyakumari in India, and the western coast of Sri Lanka.... , western South Africa South Africa The Republic of South Africa, also known by Official names of South Africa, is a country located at the southern tip of the continent of Africa.... , eastern New Zealand New Zealand New Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses , and numerous Islands of New Zealand, most notably Stewart Island/Rakiura and the Chatham Islands.... and the California California California is a U.S. state on the West Coast of the United States of the United States, along the Pacific Ocean. It is bordered by Oregon to the north, Nevada to the east, Arizona to the southeast, and to the south the Mexico state of Baja California.... coast.

Prominent gyres
* The Humboldt Current Humboldt Current The Humboldt Current is a cold, low-salinity ocean current that flows north-westward along the west coast of South America from the southern tip of Chile to northern Peru.... . This gyre produces a cold, low-salinity Salinity Salinity is the saltiness or dissolved salt content of a body of water. Salinity in Australian English and North American English may also refer to the salt in soil .... ocean current that flows north-westward along the west coast of South America from the southern tip of Chile Chile Chile, officially the Republic of Chile , is a country in South America occupying a long and narrow coastal strip wedged between the Andes mountains and the Pacific Ocean.... to northern Peru Peru Peru , officially the Republic of Peru , is a country in western South America. It is bordered on the north by Ecuador and Colombia, on the east by Brazil, on the southeast by Bolivia, on the south by Chile, and on the west by the Pacific Ocean.... . This results in the most prominent upwelling Upwelling An Upwelling is an physical oceanography phenomenon that involves wind-driven motion of dense, cooler, and usually nutrient-rich water towards the ocean surface, replacing the warmer, usually nutrient-depleted surface water.... system in the world, supporting an extraordinary abundance of marine life. Upwelling occurs off Peru year-round and off Chile during the spring and summer. Approximately 18-20% of the world’s fish catch comes from the Humboldt Current LME. The species are mostly pelagic: sardine Sardine Sardines, or pilchards, are a group of several types of small, oily fish related to herrings, family Clupeidae. Sardines were named after the island of Sardinia, where they were once in abundance.... s, anchovie Anchovy The anchovies are a Family of small, common salt-water fish. There are about 140 species in 16 genera, found in the Atlantic, Indian, and Pacific Oceans.... s and jack mackerel. The LME’s high primary and secondary productivity supports other important fishery resources as well as marine mammals. The California Current California Current The California Current is a Pacific Ocean ocean current that moves south along the western coast of North America, beginning off southern British Columbia, and ending off southern Baja California.... .This is a Pacific Ocean Pacific Ocean The Pacific Ocean is the largest of the Earth's oceanic divisions. Its name is derived from the Latin name Mare Pacificum, "peaceful sea", bestowed upon it by the Portugal explorer Ferdinand Magellan.... current Ocean current An ocean current is continuous, directed movement of ocean water. The currents are generated from the forces acting upon the water like the Earth's rotation, the wind, the temperature, salinity differences and the tide.... that moves south along the western coast of North America North America North America is the northern continent of the Americas, situated in the Earth's northern hemisphere and almost totally in the western hemisphere.... , beginning off southern British Columbia British Columbia British Columbia is the westernmost of Canada's Provinces and territories of Canada and is famed for its natural beauty, as reflected in its Latin motto, Splendor sine occasu .... , and ending off southern Baja California Baja California Baja California is the northernmost States of Mexico of Mexico. Before becoming a state in 1953, the area was known as the North Territory of Baja California.... . The movement of northern waters southward makes the coast Coast The coast is defined as that part of the land adjoining or near the ocean or its saltwater arms. A precise line that can be called a coastline cannot be determined due to the process of tides.... al waters cooler than coastal areas of comparable latitude Latitude Latitude, usually denoted symbolically by the Greek letter phi gives the location of a place on Earth north or south of the equator. Lines of Latitude are the horizontal lines shown running east-to-west on maps .... on the east coast of the United States United States The United States of America is a Federal government constitutional republic comprising U.S. state and a federal district. The country is situated mostly in central North America, where its Contiguous United States and Washington, D.C., the Capital districts and territories, lie between the Pacific Ocean and Atlantic Oceans, Borders of the U... . Extensive upwelling Upwelling An Upwelling is an physical oceanography phenomenon that involves wind-driven motion of dense, cooler, and usually nutrient-rich water towards the ocean surface, replacing the warmer, usually nutrient-depleted surface water.... of colder sub-surface waters occurs, caused by the prevailing northwesterly winds acting through the Ekman Effect. The winds drive surface water to the right of the wind flow, that is offshore, which draws water up from below to replace it. The upwelling further cools the already cool California Current. The cold water is highly productive due to the upwelling, which brings to the surface nutrient-rich sediments, supporting large populations of whale Whale Whales are marine mammals of order Cetacea which are neither dolphinsmembers, in other words, of the families Oceanic dolphin or River dolphinnor porpoises.... s, seabird Seabird Seabirds are birds that have adaptation to life within the marine environment. While seabirds vary greatly in lifestyle, behavior and physiology, they often exhibit striking convergent evolution, as the same environmental problems and feeding ecological niche have resulted in similar adaptations.... s and important fisheries. During El Niño events, the California Current is disrupted, leading to declines in phytoplankton Phytoplankton Phytoplankton are the autotrophic component of the plankton community. The name comes from the Greek language words phyton, or "plant", and p?a??t?? , meaning "wanderer" or "drifter".... , resulting in cascading effects up the food chain, such as declines in fisheries, seabird breeding failures and marine mammal mortality. In 2005, a failure in the otherwise predictable upwelling events, unassociated with El Niño, caused a collapse in krill Krill Krill are a type of shrimp-like marine invertebrate animal. These small crustaceans are important organisms of the zooplankton, particularly as food for baleen whales, manta rays, whale sharks, crabeater seals, and other pinniped, and a few seabird species that feed almost exclusively on them.... in the current, leading to similar effects.

Biomass

In the ocean, the food chain Food chain Food chains, also called, food networks and/or trophic social networks, describe the eating relationships between species within an ecosystem.... typically follows the course: Phytoplankton ? zooplankton ? predatory zooplankton ? filter feeder Filter feeder Filter feeders are animals that feed by straining suspended matter and food particles from water, typically by passing the water over a specialized filtering structure.... s ? predatory fish Phytoplankton Phytoplankton Phytoplankton are the autotrophic component of the plankton community. The name comes from the Greek language words phyton, or "plant", and p?a??t?? , meaning "wanderer" or "drifter".... is usually the primary producer (the first level in the food chain or the first trophic level Trophic level In ecology, trophic dynamics is the system of trophic levels , which describe the position that an organism occupies in a food chain — what an organism eats, and what eats the organism.... ). Phytoplankton converts inorganic carbon into protoplasm Protoplasm Protoplasm is the living contents of a cell that are surrounded by a plasma membrane. This term is not commonly used in modern cell biology. Protoplasm is composed of a mixture of small molecules such as ions, amino acids, monosaccharides and water, and macromolecules such as nucleic acids, proteins, lipids and polysaccharides.... . Phytoplankton is consumed by microscopic animals called zooplankton Zooplankton Zooplankton are the heterotrophic type of plankton. Plankton are organisms drifting in the Pelagic zone of oceans, seas, and bodies of fresh water.... . Tthese are the second level in the food chain, and include krill Krill Krill are a type of shrimp-like marine invertebrate animal. These small crustaceans are important organisms of the zooplankton, particularly as food for baleen whales, manta rays, whale sharks, crabeater seals, and other pinniped, and a few seabird species that feed almost exclusively on them.... , the larva Larva A larva is a young form of animal with indirect developmental biology, going through or undergoing metamorphosis .The larva can look completely different from the adult form, for example, a caterpillar differs from a butterfly.... of fish, squid, lobsters and crabs - as well as the small crustacean Crustacean Crustaceans are a large group of arthropods, comprising almost 52,000 described species , and are usually treated as a subphylum . They include various familiar animals, such as crabs, lobsters, crayfish, shrimp, krill and barnacles.... s called copepod Copepod Copepods are a group of small crustaceans found in the sea and nearly every fresh water habitat . Many species are planktonic , but more are benthos , and some continental species may live in limno-terrestrial habitats and other wet terrestrial places, such as swamps, under leaf fall in wet forests, bogs, springs, ephemeral ponds and puddle... s, and many other types. Zooplankton is consumed both by other, larger predatory zooplankters and by fish (the third level in the food chain). Fish that eat zooplankton could constitute the fourth trophic level, while seals consuming the fish are the fifth. Alternatively, for example, whales may consume zooplankton directly - leading to an environment with one less trophic level.

Primary biomass
Global primary production can be estimated from satellite Satellite In the context of spaceflight, a satellite is an Physical body which has been placed into orbit by human endeavor. Such objects are sometimes called artificial satellites to distinguish them from natural satellites such as the Moon.... observations. Satellites scan the normalised difference vegetation index (NDVI) over terrestrial habitats, and scan sea-surface chlorophyll Chlorophyll Chlorophyll is a green pigment found in most plants, algae, and cyanobacteria. Its name is derived from Greek language: ?????? and f????? .... levels over oceans. This results in 56.4 billion tonne Tonne A tonne or metric ton , also referred to as a *metric tonne, is a measurement of mass equal to 1,000 kilograms, or 2204.6226 pounds.... s C/yr (53.8%), for terrestrial primary production, and 48.5 billion tonnes C/yr for oceanic primary production.. Thus, the total photoautotrophic primary production for the Earth is about 104.9 billion tonnes C/yr. This translates to about 426 gC/m²/yr for land production (excluding areas with permanent ice cover), and 140 gC/m²/yr for the oceans. However, there is a much more significant difference in standing stocks Population density Population density* is a measurement of population per unit area or unit volume. It is frequently applied to living organisms, and particularly to humans.... - while accounting for almost half of total annual production, oceanic autotroph Autotroph An autotroph is an organism that produces complex organic compounds from simple inorganic molecules using energy from light or inorganic chemical reactions.... s account for only about 0.2% of the total biomass. The most successful animal Animal Animals are a major group of multicellular, eukaryotic organisms of the Kingdom Animalia or Metazoa. Their body plan eventually becomes fixed as they develop, although some undergo a process of metamorphosis later on in their life.... species, in terms of biomass, is probably the Antarctic krill Antarctic krill Antarctic krill is a species of krill found in the Antarctica waters of the Southern Ocean. Antarctic krill are shrimp-like invertebrates or crustaceans that live in large schools, called swarms, sometimes reaching densities of 10,000?30,000 individual animals per cubic meter.... , Euphausia superba, with a biomass of about 500 million tonne Tonne A tonne or metric ton , also referred to as a *metric tonne, is a measurement of mass equal to 1,000 kilograms, or 2204.6226 pounds.... s. However, as a group, the small aquatic crustacean Crustacean Crustaceans* are a large group of arthropods, comprising almost 52,000 described species , and are usually treated as a subphylum . They include various familiar animals, such as crabs, lobsters, crayfish, shrimp, krill and barnacles.... s called copepod Copepod Copepods are a group of small crustaceans found in the sea and nearly every fresh water habitat . Many species are planktonic , but more are benthos , and some continental species may live in limno-terrestrial habitats and other wet terrestrial places, such as swamps, under leaf fall in wet forests, bogs, springs, ephemeral ponds and puddle... s form the largest animal biomass on earth.
Biome Biome Biomes are Climateally and geographically defined areas of ecologically similar climatic conditions such as Community of plants, animals, and Soil biology, and are often referred to as ecosystems.... Ecosystem Ecosystem An ecosystem is a natural unit consisting of all plants, animals and micro-organisms in an area functioning together with all of the non-living physical factors of the environment.... Type	Area	Mean Net Primary Production	World Primary Production	Mean biomass	World biomass	Minimum replacement rate
	(million km²)	(gram dryC / m² / year)	(billion tonnes / year)	(kg dryC / m²)	(billion tonnes)	(years)
Open ocean	332.00	125.00	41.50	0.003	1.00	0.02
Upwelling Upwelling An Upwelling is an physical oceanography phenomenon that involves wind-driven motion of dense, cooler, and usually nutrient-rich water towards the ocean surface, replacing the warmer, usually nutrient-depleted surface water.... zones	0.40	500.00	0.20	0.02	0.01	0.04
Continental shelf Continental shelf The continental shelf is the extended perimeter of each continent and associated coastal plain, and was part of the continent during the glacial periods, but is undersea during Ice age such as the current epoch by relatively shallow seas and Bay....	26.60	360.00	9.58	0.01	0.27	0.03
Algal bed Algae Algae are a large and diverse group of simple, typically autotrophic organisms, ranging from unicellular to multicellular forms. The largest and most complex marine forms are called seaweeds.... s and reef Reef In nautical terminology, a reef is a Rock , bar , or other feature lying beneath the surface of the water .Many reefs result from abiotic processes?deposition of sand, wave erosion planning down rock outcrops, and other natural processes?but the best-known reefs are the coral reefs of tropical waters developed through biotic processes do... s	0.60	2,500.00	1.50	2.00	1.20	0.80
Estuaries Estuary An estuary is a semi-enclosed coastal body of water with one or more rivers or streams flowing into it, and with a free connection to the open sea.... & mangroves	1.40	1,500.00	2.10	1.00	1.40	0.67
Total marine	361.00	152.01	54.88	0.01	3.87	0.07
Lake Lake A lake is a terrain feature , a body of liquid on the surface of a world that is localized to the bottom of basin and moves slowly if it moves at all.... s and stream Stream A stream is a body of water less than 60 feet wide with a current , confined within a stream bed and stream banks. Depending on its locale or certain characteristics, a stream may be referred to as brook, beck, Burn , creek, crick, kill, lick , rill, river syke, bayou, rivu... s	2.00	250.00	0.50	0.02	0.04	0.08
Terrestrial Biomass Biomass, as a renewable energy source, refers to living and recently dead biological material that can be used as fuel or for industrial production....	147.00	554.51	114.90	12.55	1,873.38	16.15
Grand total	510.00	333.87	170.28	3.68	1,877.29	11.02
Source: ; Ecological Studies Vol 14 (Berlin) Darci and Taylre are biomass specialists.

Habitats

[Marine biology#Oceanic habitats|Aquatic habitats]] have been classified into marine

Ecoregion

An ecoregion , sometimes called a bioregion, is an ecology and geographically defined area smaller than a "realm" or "ecozone". Ecoregions cover relatively large areas of land or water, and contain characteristic, geographically distinct assemblages of natural community and species....
s by the Worldwide Fund for Nature (WWF). An ecoregion is defined as a "relatively large unit of land or water containing a characteristic set of natural communities that share a large majority of their species, dynamics, and environmental conditions (Dinerstein et al. 1995, TNC 1997). |}

Coastal waters

* Estuaries Estuary An estuary is a semi-enclosed coastal body of water with one or more rivers or streams flowing into it, and with a free connection to the open sea.... are semi-enclosed coastal bodies of water Water Water is a common chemical substance that is essential for the survival of all known forms of life. In typical usage, water refers only to its liquid form or States of matter, but the substance also has a solid state, ice, and a gaseous state, water vapor or steam.... with one or more river River A river is a natural stream of water, usually freshwater, flowing toward an ocean, a lake, or another stream. In some cases a river flows into the ground or dries up completely before reaching another body of water.... s or stream Stream A stream is a body of water less than 60 feet wide with a current , confined within a stream bed and stream banks. Depending on its locale or certain characteristics, a stream may be referred to as brook, beck, Burn , creek, crick, kill, lick , rill, river syke, bayou, rivu... s flowing into therm, and with a free connection to the open sea SEA See also: Sea and seasThe three-letter acronym SEA may refer to:People/organizations/businessesScientists and Engineers for America, a pro-science political advocacy group.... . Estuaries are often associated with high rates of biological productivity. They are small, in demand, impacted by events far upstream or out at sea, and concentrate materials such as pollutants and sediments. Lagoons are bodies of comparatively shallow salt or brackish water Brackish water Brackish water* is water that has more salinity than fresh water, but not as much as seawater. It may result from mixing of seawater with fresh water, as in estuary, or it may occur in brackish fossil aquifers.... separated from the deeper sea SEA See also: Sea and seasThe three-letter acronym SEA may refer to:People/organizations/businessesScientists and Engineers for America, a pro-science political advocacy group.... by a shallow or exposed sandbank Bar (landform) A shoal* or sandbar is a somewhat linear landform within or extending into a body of water, typically composed of sand, silt or small pebbles.... , coral reef Reef In nautical terminology, a reef is a Rock , bar , or other feature lying beneath the surface of the water .Many reefs result from abiotic processes?deposition of sand, wave erosion planning down rock outcrops, and other natural processes?but the best-known reefs are the coral reefs of tropical waters developed through biotic processes do... , or similar feature. Lagoon refers to both coastal lagoons formed by the build-up of sandbanks or reefs along shallow coastal waters, and the lagoons in atolls, formed by the growth of coral reefs on slowly sinking central islands. Lagoons that are fed by freshwater streams are estuaries. The intertidal zone Intertidal zone The intertidal zone is the area that is exposed to the air at low tide and submerged at high tide, for example, the area between tide marks. This area can include many different types of habitats, including steep rocky cliffs, sandy beaches, or wetlands .... (foreshore) is the area that is exposed to the air AIR Air is the part of Earth's atmosphere that humans breath and as such Air .Air may also refer to:... at low tide and submerged at high tide High Tide High Tide was a band formed in 1969 by Tony Hill , Simon House , Pete Pavli and Roger Hadden . The trademark of their first album Sea Shanties was the constant battle between the electric guitar of Tony Hill and the electric violin of Simon House.... , for example, the area between tide marks. This area can include many different types of habitats, including steep rocky cliffs, sandy beaches or vast mudflat Mudflat Mudflats are coastal wetlands that form when mud is deposited by tides or rivers. They are found in sheltered areas such as bays, bayous, lagoons, and estuaries.... s. The area can be a narrow strip, as in Pacific islands that have only a narrow tidal range, or can include many meters of shoreline where shallow beach slope interacts with high tidal excursion. The littoral zone is the part of the ocean closest to the shore. The word littoral comes from the Latin Latin Latin is an Italic language, historically spoken in Latium and Ancient Rome. Through the Military history of the Roman Empire, Latin spread throughout the Mediterranean and a large part of Europe.... litoralis, which means seashore. The littoral zone extends from the high water mark to near shore areas that are permanently submerged, and includes the intertidal zone. Definitions vary. Encyclopaedia Britannica defines the littoral zone in a thoroughly vague way as the "marine ecological realm that experiences the effects of tidal and longshore currents and breaking waves to a depth of 5 to 10 metres (16 to 33 feet) below the low-tide level, depending on the intensity of storm waves". The US Navy defines it as extending "from the shoreline to 600 feet (183 meters) out into the water" The sublittoral zone Neritic zone The neritic zone, also called the Littoral zone#Sublittoral zone, is the part of the ocean extending from the low tide mark to the edge of the continental shelf, with a relatively shallow depth extending to about 200 meters .... is the part of the ocean extending from the seaward edge of the littoral zone to the edge of the continental shelf Continental shelf The continental shelf is the extended perimeter of each continent and associated coastal plain, and was part of the continent during the glacial periods, but is undersea during Ice age such as the current epoch by relatively shallow seas and Bay.... . It is sometimes called the neritic zone. Websters defines the neritic zone as the region of shallow water adjoining the seacoast. The word neritic perhaps comes from the new Latin New Latin The term New Latin or Neo-Latin is used to describe a form the Latin language used after the end of the Medieval Latin period to c. 1900, and in a very limited fashion, down to the present day.... nerita, which refers to a genus of marine snails, 1891. The sublittoral zone is relatively shallow, extending to about 200 meters (100 fathoms), and generally has well-oxygenated water, low water pressure, and relatively stable temperature and salinity Salinity Salinity is the saltiness or dissolved salt content of a body of water. Salinity in Australian English and North American English may also refer to the salt in soil .... levels. These, combined with presence of light and the resulting photosynthetic life, such as phytoplankton Phytoplankton Phytoplankton are the autotrophic component of the plankton community. The name comes from the Greek language words phyton, or "plant", and p?a??t?? , meaning "wanderer" or "drifter".... and floating sargassum Sargassum Sargassum is a genus of generally planktonic macroalgae in the order Fucales. It is named for the Atlantic Ocean's Sargasso Sea, which hosts a large amount of several species of Sargassum.... , make the sublittoral zone the location of the majority of sea life. Voigt, Brian (1998) Washington State Department of Ecology, publication 98-105 Pawson, M G; Pickett, G D and Walker, P (2002) Science Series, Technical Report 116.

Continental shelves

Continental shelves are the extended perimeters of each continent Continent A continent is one of several large landmasses on Earth. They are generally identified by convention rather than any strict criteria, with seven regions commonly regarded as continents ? they are : Asia, Africa, North America, South America, Antarctica, Europe, and Australia .... and associated coastal plain Coastal plain A coastal plain is an area of flat, low-lying land adjacent to a seacoast and separated from the interior by other features. One of the world's longest coastal plains is located in western South America.... , which is covered during interglacial periods Ice age The general term "ice age" or, more precisely, "glacial age" denotes a geological period of long-term reduction in the temperature of the Earth's surface and atmosphere, resulting in an expansion of continental ice sheets, polar ice sheets and alpine glaciers.... such as the current epoch by relatively shallow sea SEA See also: Sea and seasThe three-letter acronym SEA may refer to:People/organizations/businessesScientists and Engineers for America, a pro-science political advocacy group.... s (known as shelf seas) and gulfs Headlands and bays Headlands and bays* are two related features of the coastal environment.... . The shelf usually ends at a point of decreasing slope (called the shelf break). The sea floor below the break is the continental slope. Below the slope is the continental rise, which finally merges into the deep ocean floor, the abyssal plain Abyssal plain Abyssal plains are flat or very gently sloping areas of the deep ocean basin floor. They are among the Earth's flattest and smoothest regions and the least explored.... . The continental shelf and the slope are part of the continental margin Continental margin The continental margin is the zone of the ocean floor that separates the thin oceanic crust from thick continental crust. Continental margins constitute about 28% of the oceanic area.... . Continental shelves are shallow (averaging 140 metres or 460 feet), and the sunlight available means they can team with life. The shallowest parts of the continental shelf are called fishing banks. There the sunlight penetrates to the seafloor and the plankton Plankton Plankton consist of any drifting organisms that inhabit the pelagic zone of oceans, seas, or bodies of fresh water. Plankton are defined by their ecological niche rather than their Phylogenetics or taxonomy classification.... , on which fish feed, thrive.

Continental shelves : Details
The character of the shelf changes dramatically at the shelf break, where the continental slope begins. With a few exceptions, the shelf break is located at a remarkably uniform depth of roughly 140 m (460 ft); this is likely a hallmark of past ice ages, when sea level was lower than it is now. The width of the continental shelf varies considerably – it is not uncommon for an area to have virtually no shelf at all, particularly where the forward edge of an advancing oceanic plate Oceanic crust Oceanic crust is the part of Earth's lithosphere that surfaces in the ocean basins. Oceanic crust is primarily composed of mafic rocks, or Sima .... dives beneath continental crust Continental crust The continental crust is the layer of igneous, sedimentary, and metamorphic rocks which form the continents and the areas of shallow seabed close to their shores, known as Continental shelf.... in an offshore subduction zone such as off the coast of Chile Chile Chile, officially the Republic of Chile , is a country in South America occupying a long and narrow coastal strip wedged between the Andes mountains and the Pacific Ocean.... or the west coast of Sumatra Sumatra Sumatra is an island in western Indonesia, westernmost of the Sunda Islands. It is the largest island entirely in Indonesia , and the list of islands by area in the world .... . The largest shelf – the Siberian Shelf Siberian Shelf The Siberian Shelf, one of the Arctic shelves, is the largest continental shelf of the Earth, a part of the continental shelf of Russia. It extends from the continent of Eurasia in the general area of North Siberia into the Arctic Ocean.... in the Arctic Ocean Arctic Ocean The Arctic Ocean, located in the Northern Hemisphere and mostly in the Arctic North Pole region, is the smallest and shallowest of the world's five major oceanic divisions.... – stretches to 1500 kilometers (930 mile Mile A mile is a Units of measurement of length, usually used to measure distance, in a number of different systems. In contemporary English contexts, mile most commonly refers to the statute mile of 5,280 Feet or the nautical mile of 1,852 meters .... s) in width. The South China Sea South China Sea The South China Sea is a marginal seasouth of China,west of the Philippines,north west of Sabah , Sarawak and Brunei,north of Indonesia,... lies over another extensive area of continental shelf, the Sunda Shelf Sunda Shelf Geology, the Sunda Shelf is an extension of the continental shelf of Southeast Asia, covered during interglacials by the South China Sea, which isolates as islands Borneo, Sumatra Java and smaller islands.... , which joins Borneo Borneo Borneo is the List of islands by area and is located at the centre of Maritime Southeast Asia. Administratively, this island is divided between Indonesia, Malaysia and Brunei.... , Sumatra, and Java to the Asian mainland. Other familiar bodies of water that overlie continental shelves are the North Sea North Sea The North Sea is a marginal sea, epeiric sea on the European continental shelf. The Dover Strait and the English Channel in the south and the Norwegian Sea in the north connect it to the Atlantic Ocean.... and the Persian Gulf Persian Gulf The Persian Gulf, in the Southwest Asian region, is an extension of the Indian Ocean located between Iran and the Arabian Peninsula. Historically and commonly known as the Persian Gulf, this body of water is sometimes Persian Gulf naming dispute referred to as the Arabian Gulf by certain Arab countries or simply The Gulf, although nei... . The average width of continental shelves is about 80 km (50 mi). The depth of the shelf also varies, but is generally limited to water shallower than 150 m Metre The metre or meter is a Unit of measurement of length. It is the SI base unit of length in the metric system and in the International System of Units , used around the world for general and scientific purposes.... (490 ft). Combined with the sunlight available in shallow waters, the continental shelves teem with life compared to the biotic desert of the oceans' abyssal plain Abyssal plain Abyssal plains are flat or very gently sloping areas of the deep ocean basin floor. They are among the Earth's flattest and smoothest regions and the least explored.... . The pelagic (water column) environment of the continental shelf constitutes the neritic zone Neritic zone The neritic zone, also called the Littoral zone#Sublittoral zone, is the part of the ocean extending from the low tide mark to the edge of the continental shelf, with a relatively shallow depth extending to about 200 meters .... , and the benthic (sea floor) province of the shelf is the sublittoral zone.

Coral reefs

Coral reef Coral reef Coral reefs are aragonite structures produced by living organisms. In most reefs the predominant organisms are colonial cnidarian that secrete an exoskeleton of calcium carbonate.... s are aragonite Aragonite Aragonite is a carbonate mineral, one of the two common, naturally occurring polymorphism of calcium carbonate, calciumcarbonoxygen3.... structures produced by living organisms, found in shallow, tropical marine waters with little to no nutrients in the water. High nutrient levels such as those found in runoff from agricultural areas can harm the reef by encouraging the growth of algae Algae Algae are a large and diverse group of simple, typically autotrophic organisms, ranging from unicellular to multicellular forms. The largest and most complex marine forms are called seaweeds.... . Although corals are found both in temperate and tropical waters, reefs are formed only in a zone extending at most from 30°N to 30°S of the equator.

Coral reefs : Details
Coral reefs are estimated to cover 284,300 square kilometres, with the Indo-Pacific Indo-Pacific The Indo-Pacific is a biogeography region of the earth's seas, comprising the tropical waters of the Indian Ocean, the western and central Pacific Ocean, and the seas connecting the two in the general area of Indonesia.... region (including the Red Sea Red Sea The Red Sea is a salt water inlet of the Indian Ocean between Africa and Asia. The connection to the ocean is in the south through the Bab el Mandeb sound and the Gulf of Aden.... , Indian Ocean Indian Ocean The Indian Ocean is the third largest of the world's oceanic divisions, covering about 20% of the water on the Earth's surface. It is bounded on the north by Asia ; on the west by Africa; on the east by Indochina, the Sunda Islands, and Australia; and on the south by the Southern Ocean .... , Southeast Asia Southeast Asia Southeast Asia or Southeastern Asia is a subregion of Asia, consisting of the countries that are geographically south of China, east of India and north of Australia.... and the Pacific) accounting for 91.9% of the total. Southeast Asia accounts for 32.3% of that figure, while the Pacific including Australia Australia Australia, officially the Commonwealth of Australia, is a country in the southern hemisphere comprising the Australia of the world's smallest continent, the major island of Tasmania, and numerous list of islands of Australia in the Indian Ocean and Pacific Oceans.... accounts for 40.8%. Atlantic and Caribbean Caribbean The Caribbean is a region consisting of the Caribbean Sea, its islands , and the surrounding coasts. The region is located southeast of the Gulf of Mexico and Northern America, east of Central America, and to the north of South America.... coral reefs only account for 7.6% of the world total. Coral reefs are either restricted or absent from the west coast of the Americas Americas The Americas are the region of the Western hemisphere that consists of the continents of North America and South America with their associated islands and regions.... , as well as the west coast of Africa Africa Africa is the world's second-largest and second most-populous continent, after Asia. At about 30.2 million km? including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area.... . This is due primarily to upwelling Upwelling An Upwelling is an physical oceanography phenomenon that involves wind-driven motion of dense, cooler, and usually nutrient-rich water towards the ocean surface, replacing the warmer, usually nutrient-depleted surface water.... and strong cold coastal currents that reduce water temperatures in these areas. Corals are also restricted from off the coastline of South Asia South Asia South Asia, also known as Southern Asia, is the southern region of the Asian continent, which comprises the sub-Himalayan countries and, for some authorities , also includes the adjoining countries on the west and the east.... from Pakistan Pakistan Pakistan , officially the Islamic Republic of Pakistan, is a country located in South Asia and borders Central Asia and the Middle East. It has a 1,046 kilometre coastline along the Arabian Sea and Gulf of Oman in the south, and is bordered by Afghanistan and Iran in the west, India in the east and People's Republic of China in th... to Bangladesh Bangladesh , officially the People's Republic of Bangladesh is a country in South Asia. It is bordered by India on all sides except for a small border with Burma to the far southeast and by the Bay of Bengal to the south.... . They are also restricted along the coast around north-eastern South America South America South America is the southern continent of the Americas, situated entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere.... and Bangladesh Bangladesh , officially the People's Republic of Bangladesh is a country in South Asia. It is bordered by India on all sides except for a small border with Burma to the far southeast and by the Bay of Bengal to the south.... due to the release of vast quantities of freshwater from the Amazon Amazon River The Amazon River of South America is the list of rivers by length in the world by volume, with a total river flow greater than the next top eight largest rivers combined.... and Ganges Rivers respectively. Famous coral reefs and reef areas of the world include: The Great Barrier Reef Great Barrier Reef The Great Barrier Reef is the largest coral reef system in the world, composed of over 2,900 individual reefs and 900 islands stretching for 2,600 kilometres over an area of approximately .... - largest coral reef system in the world, Queensland, Australia Queensland Queensland is a States and territories of Australia of Australia, occupying the north-eastern section of the mainland continent. It is bordered by the Northern Territory to the west, South Australia to the south-west and New South Wales to the south.... ; The Belize Barrier Reef Belize Barrier Reef The Belize Barrier Reef is a series of coral reefs straddling the coast of Belize, roughly offshore in the north and in the south within the country limits.... - 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 Red Sea The Red Sea is a salt water inlet of the Indian Ocean between Africa and Asia. The connection to the ocean is in the south through the Bab el Mandeb sound and the Gulf of Aden.... Coral Reef - located off the coast of Egypt and Saudi Arabia. Pulley Ridge Pulley Ridge Pulley Ridge is a coral reef off the coast of southwestern Florida, United States . The reef lies 100 miles west of the Tortugas Ecological Reserve and stretches north about 60 miles.... - deepest photosynthetic coral reef, Florida Florida Florida is a U.S. state located in the Southeastern United States of the United States, bordering Alabama to the northwest and Georgia to the northeast.... Many of the numerous reefs found scattered over the Maldives Maldives The Maldives , or Maldive Islands, officially the Republic of Maldives, is an island nation consisting of a Atolls of the Maldivess stretching south of India's Lakshadweep islands between Minicoy Island and the Chagos Archipelago, and about seven hundred kilometres south-west of Sri Lanka in the Laccadive Sea of Indian Ocean.... The New Caledonia Barrier Reef New Caledonia Barrier Reef The New Caledonia Barrier Reef is located in New Caledonia in the Oceania, and is the second-longest coral reef in the world, after Australia's Great Barrier Reef.... - second longest double barrier reef in the world, with a length of about 1500 km. Coral reefs support an extraordinary biodiversity Biodiversity Biodiversity is the variation of life forms within a given ecosystem, biome, or for the entire Earth. Biodiversity is often used as a measure of the health of biological systems.... ; although they are located in nutrient-poor tropical waters. The process of nutrient cycling Biogeochemical cycle In ecology and Earth science, a biogeochemical cycle or nutrient cycle is a pathway by which a chemical element or molecule moves through both biotic and abiotic compartments of Earth.... 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 Fish A fish is any marine biology vertebrate animal that is typically ectothermic , covered with scale , and equipped with two sets of paired fins and several unpaired fins.... , such as the colorful parrotfish Parrotfish Parrotfish are mostly tropical, perciform marine fish of the family Scaridae. Abundant on shallow reefs of the Red Sea, Atlantic Ocean, Indian Ocean and Pacific Oceans, the parrotfish family contains ten genera and about 90 species.... , angelfish, damselfish Damselfish Damselfish refers to members of the family Pomacentridae, except those of the two genera Amphiprion and Premnas. Other species within the family have common names that include the word 'damselfish', but in almost all cases this is qualified with an adjective or other descriptor.... and butterflyfish Butterflyfish The butterflyfish are a group of conspicuous tropical marine fish of the family Chaetodontidae; the bannerfish and coralfish are also included in this group.... . Other fish groups found on coral reefs include grouper Grouper For other meanings, see Grouper .Groupers are fish of any of a number of genus in the subfamily Epinephelinae of the family Serranidae, in the order Perciformes.... s, snappers, grunts and wrasse Wrasse The wrasses are a family , Labridae, of marine fish, many of which are brightly colored. The family is large and diverse, with about 500 species in 60 genera.... s. Over 4,000 species of fish inhabit coral reefs. 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'. Reefs are also home to a large variety of other organisms, including sponges Sea sponge The sponges or poriferans are animals of the phylum Porifera . Their bodies consist of an outer thin layer of cells, the pinacoderm and an inner mass of cells and skeletal elements, the choanoderm.... , Cnidaria Cnidaria Cnidaria Cnidarians were for a long time grouped with Ctenophores in the phylum Coelenterata, but increasing awareness of their differences caused them to be placed in separate phyla.... ns (which includes some types of corals and jellyfish Jellyfish Jellyfish are free-swimming members of the phylum Cnidaria. They have several different morphologies that represent several different cnidarian classes including the Scyphozoa , Staurozoa , Cubozoa , and Hydrozoa .... ), worm Worm A worm is a common name given to a diverse group of invertebrate animals that have a long, soft body and no legs. There are hundreds of thousands of species of worms, 2,700 of these are earthworms.... s, crustacean Crustacean Crustaceans are a large group of arthropods, comprising almost 52,000 described species , and are usually treated as a subphylum . They include various familiar animals, such as crabs, lobsters, crayfish, shrimp, krill and barnacles.... s (including shrimp Shrimp Shrimp are swimming, Decapoda crustaceans classified in the infraorder Caridea, found widely around the world in both fresh water and seawater. Adult shrimp are Filter feeder benthic animals living close to the bottom.... , spiny lobster Spiny lobster Spiny lobsters, also known as langouste or rock lobsters are a family of about 45 species of Achelata crustaceans, in the Decapoda Reptantia.... s and crab Crab Crabs are Decapoda crustaceans of the infraorder Brachyura, which typically have a very short projecting "tail" , or where the reduced abdomen is entirely hidden under the thorax.... s), molluscs (including cephalopod Cephalopod The cephalopods are the mollusc class Cephalopoda characterized by bilateral symmetry, a prominent head, and a modification of the mollusk foot, a muscular hydrostat, into the form of cephalopod arms or tentacles.... s), echinoderm Echinoderm Echinoderms are a Phylum of Marine animals . Echinoderms are found at every ocean depth, from the intertidal zone to the abyssal zone.Aside from the problematic Arkarua, the first definitive members of the phylum appeared near the start of the Cambrian period.... s (including starfish, sea urchins and sea cucumber Sea cucumber Holothuroidea is a class of marine animals with an elongated body and leathery skin, which is found on the sea floor worldwide. Many holothurian species and genera, informally known as sea cucumbers, are targeted for human consumption.... s), sea squirts, sea turtle Sea turtle Sea turtles are turtles found in all the world's oceans except the Arctic Ocean. There are seven living species of sea turtles: Flatback Sea Turtle, Green Sea Turtle, Hawksbill turtle, Kemp's Ridley, leatherback sea turtle, Loggerhead Sea Turtle and Olive Ridley Sea Turtle.... s and sea snake Sea snake Sea snakes, or seasnakes, are venomous snake Elapidae snakes that inhabit marine environments for most or all of their lives. Though they evolved from terrestrial ancestors, most are extensively adapted to a fully aquatic life and are unable to even move on land, except for the genus Laticauda, which retain ancestral characteristics... s. Human activity may represent the greatest threat to coral reefs living in Earth's oceans. In particular, pollution Pollution Pollution is the introduction of contaminants into an environment that causes instability, disorder, harm or discomfort to the ecosystem i.e. physical systems or living organisms .... 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 Live food fish trade The live food fish trade is a global system that links fishing communities with markets, primarily in Hong Kong and mainland China. Many of the fish are captured on coral reefs in Southeast Asia or the Pacific Island nations.... has been implicated as a driver of decline due to the use of cyanide Cyanide A cyanide is any chemical compound that contains the nitrile , which consists of a carbon atom chemical bond to a nitrogen atom. Inorganic cyanides are hydrogen cyanide salts in which cyanide is generally the anion CN-.... and disaster for peoples living in the tropics. Hughes, et al., (2003), writes that "with increased human population World population The world population is the total number of living humans on Earth at a given time. As of March 2009, the world's population is estimated to be about 6.76 1,000,000,000 .... and improved storage and transport systems, the scale of human impacts on reefs has grown exponentially. For example, markets for fishes and other natural resource Natural resource Renewable resources Renewable resources are sometimes living resources,, which can restock themselves if used sustainably and not over- harvested.... s have become global, supplying demand for reef resources far removed from their tropical sources." 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 Carbon dioxide sink A carbon sink is a natural or manmade reservoir that accumulates and stores some carbon-containing chemical compound for an indefinite period.... , changes in Earth's atmosphere Earth's atmosphere The Earth's atmosphere is a layer of gases surrounding the planet Earth that is retained by the Earth's gravity. Dry air contains roughly 78.08% nitrogen, 20.95% oxygen, 0.93% argon, 0.038% Carbon dioxide in the Earth's atmosphere, and trace amounts of other gases.... , ultraviolet light, ocean acidification Ocean acidification Ocean acidification is the name given to the ongoing decrease in the pH of the Earth's oceans, caused by their uptake of anthropogenic carbon dioxide from the Earth's atmosphere.... , biological virus Virus A virus is a Optical microscope#Limitations of light microscopes infectious agent that is unable to grow or reproduce outside a host cell . Viruses infect all cellular life.... , impacts of dust storms carrying agents to far flung reef systems, various pollutants, impacts of algal bloom Algal bloom An algal bloom is a rapid increase in the population of algae in an aquatic system. Algal blooms may occur in freshwater as well as marine environments.... s 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 Southeast Asia coral reefs Southeast Asian coral reefs have the highest levels of biodiversity for the world's marine ecosystems. They serve many functions, such as forming the of livelihood for subsistence fishermen and even function as jewellery and construction materials.... are at risk from damaging fishing Fishing Fishing is the activity of catching fish. Fishing techniques include Fish net, Fish trap, Spearfishing, angling and Gathering seafood by hand. The term fishing may be applied to catching other aquatic animals such as different types of shellfish, squid, octopus, turtles, Edible frog and some edible marine invertebrates.... practices (such as cyanide Cyanide fishing Cyanide fishing is an illegal form of fishing common in South East Asia, which usually uses the chemical compound sodium cyanide. Since 2000, increasing restrictions on illegal dynamite fishing have led to an increasing growth in this indiscriminate method ? particularly as it can be used without generating noise.... and blast fishing Blast fishing Blast fishing or dynamite fishing is the practice of using explosives to stun or kill schools of fish for easy collection. This often illegal practice can be extremely destructive to the surrounding ecosystem, as the explosion often destroys the underlying habitat that supports the fish.... ), overfishing Overfishing Overfishing occurs when fishing activities reduce fish stocks below an acceptable level. This can occur in any body of water from a pond to the oceans.... , 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 Indonesia The Republic of Indonesia , is a transcontinental country in Southeast Asia and Oceania. Comprising Islands of Indonesia, it is the world's largest Archipelago state.... , for example has nearly 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 Coral Triangle The Coral Triangle is a geographical term referring to the waters of Indonesia, Malaysia, Papua New Guinea, Philippines, Solomon Islands and Timor-Leste with an abundance of coral reef.... 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 Johns Hopkins University The Johns Hopkins University, commonly referred to as Hopkins or JHU, is a private university research university located in Baltimore, Maryland, Maryland, United States.... ). General estimates show approximately 10% of the coral reefs around the world are already dead.Problems range from environmental effects of fishing Environmental effects of fishing File:Fishing down the food web.jpgThe environmental effects of fishing can be divided into issues that involve the availability of fish to be caught, such as overfishing, sustainable fisheries, and fisheries management; and issues that involve the impact of fishing on the environment, such as by-catch.... techniques, described above, to ocean acidification Ocean acidification Ocean acidification is the name given to the ongoing decrease in the pH of the Earth's oceans, caused by their uptake of anthropogenic carbon dioxide from the Earth's atmosphere.... . Coral bleaching Coral bleaching Coral bleaching is the loss of color of corals, due to stress-induced expulsion of symbiotic unicellular algae or due to the loss of pigmentation within the algae.... is another manifestation of the problem and is showing up in reefs across the planet. NInhabitants of Ahus Island, Manus Province Manus Province Manus Province is the smallest province in Papua New Guinea with a land area of 2,100 km?, but with more than 220,000 km? of water. The capital of the province is Lorengau and the total population is 43,387 .... , Papua New Guinea Papua New Guinea Papua New Guinea , officially the Independent State of Papua New Guinea, is a country in Oceania, occupying the eastern half of the island of New Guinea and numerous offshore islands .... , 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 Biomass Biomass, as a renewable energy source, refers to living and recently dead biological material that can be used as fuel or for industrial production.... and individual fish sizes are significantly larger in these areas than in places where fishing is completely unrestricted. 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 Southeast Asia Southeast Asia or Southeastern Asia is a subregion of Asia, consisting of the countries that are geographically south of China, east of India and north of Australia.... , where an enormous 80% of reefs are considered endangered Endangered species An endangered species is a population of an organism which is at risk of becoming extinct because it is either few in numbers, or threatened by changing environmental or predation parameters.... . Organisations as , and the are currently undertaking coral reef/atoll restoration projects. They are doing so using simple methods of plant propagation Plant propagation 'Plant propagation' is the process of artificially or naturally distributing plants.... . Other organisations as Practical Action Practical Action Practical Action is a developing country charitable trust registered in the United Kingdom which works directly in four regions of the developing world ? Latin America, East Africa, Southern Africa and South Asia, with particular concentration on Peru, Kenya, Sudan, Zimbabwe, Sri Lanka and Nepal.... have released informational documents on how to set-up coral reef restoration to the public.

Open sea

In the deep ocean, much of the ocean floor is a flat, featureless underwater desert called the abyssal plain Abyssal plain Abyssal plains are flat or very gently sloping areas of the deep ocean basin floor. They are among the Earth's flattest and smoothest regions and the least explored.... . Many pelagic fish migrate Fish migration Many types of fish migration on a regular basis, on time scales ranging from daily to annual, and over distances ranging from a few meters to thousands of kilometers.... across these pains in search of spawning or different feeding grounds. Smaller migratory fish are followed by larger predator fish and can provide rich, if temporary, fishing grounds. Strait Strait A strait or straits is a narrow, navigable channel of water that connects two larger navigable bodies of water. It most commonly refers to a channel of water that lies between two land masses, but it may also refer to a navigable channel through a body of water that is otherwise not navigable, for example because it is too shallow, or...

Seamounts

A seamount Seamount A seamount is a mountain rising from the ocean seafloor that does not reach to the water's surface , and thus is not an island. These are typically formed from extinct volcanoes, that rise abruptly and are usually found rising from a seafloor of 1,000?4,000 meters depth.... is an underwater mountain Mountain A mountain is a landform that stretches above the surrounding land in a limited area usually in the form of a peak. A mountain is generally steeper than a hill.... , rising from the seafloor that does not reach to the water's surface (sea level Sea level Mean sea level is the average height of the sea, with reference to a suitable reference surface. Defining the reference level , however, involves complex measurement, and accurately determining MSL can prove difficult.... ), and thus is not an island Island An island or isle is any piece of land that is surrounded by water. Very small islands such as emergent land features on atolls are called islets.... . They are defined by oceanographers Oceanography Oceanography , also called oceanology or marine science, is the branch of Earth science that studies the ocean. It covers a wide range of topics, including marine organisms and ecosystem dynamics; ocean currents, waves, and geophysical fluid dynamics; plate tectonics and the geology of the sea floor; and fluxes of various chemi... as independent features that rise to at least 1,000 meters above the seafloor. Seamounts are common in the Pacific Ocean. Recent studies suggest there may be 30,000 seamounts in the Pacific, about 1,000 in the Atlantic Ocean and an unknown number in the Indian Ocean.

Seamounts : Details
Seamounts often project upwards into shallower zones more hospitable to sea life, providing habitats Habitat (ecology) A habitat is an ecological or Natural_environment area that is inhabited by a particular animal or plant species. It is the natural environment in which an organism lives, or the physical environment that surrounds a species population.... for marine species that are not found on or around the surrounding deeper ocean bottom. In addition to simply providing physical presence in this zone, the seamount itself may deflect deep currents and create upwelling Upwelling An Upwelling is an physical oceanography phenomenon that involves wind-driven motion of dense, cooler, and usually nutrient-rich water towards the ocean surface, replacing the warmer, usually nutrient-depleted surface water.... . 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 whale Whale Whales are marine mammals of order Cetacea which are neither dolphinsmembers, in other words, of the families Oceanic dolphin or River dolphinnor porpoises.... s. 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. This increases the densities of the zooplankton Zooplankton Zooplankton are the heterotrophic type of plankton. Plankton are organisms drifting in the Pelagic zone of oceans, seas, and bodies of fresh water.... 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. The benthic fauna of the seamounts is dominated by suspension feeders, including sponge Sea sponge The sponges or poriferans are animals of the phylum Porifera . Their bodies consist of an outer thin layer of cells, the pinacoderm and an inner mass of cells and skeletal elements, the choanoderm.... s and true coral Coral Corals are marine organisms from the class Anthozoa and exist as small sea anemone?like polyps, typically in colonies of many identical individuals.... s. For some seamounts that peaks at 200-300 metres below the surface benthic macroalgae is common. The sedimentary infauna is dominated by polychaete Polychaete The Polychaeta or polychaetes are a class of annelid worms, generally marine. Each body segment has a pair of fleshy protrusions called parapodia that bear many bristles, called chaetae, which are made of chitin.... 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 During the 1960s, Russia Russia Russia , or the Russian Federation , is a list of countries spanning more than one continent country extending over much of northern Eurasia.... , Australia Australia Australia, officially the Commonwealth of Australia, is a country in the southern hemisphere comprising the Australia of the world's smallest continent, the major island of Tasmania, and numerous list of islands of Australia in the Indian Ocean and Pacific Oceans.... and New Zealand New Zealand New Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses , and numerous Islands of New Zealand, most notably Stewart Island/Rakiura and the Chatham Islands.... 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 Orange roughy The orange roughy, red roughy, or deep sea perch, Hoplostethus atlanticus, is a relatively large deep-sea fish belonging to the slimehead family .... (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 Fecundity Fecundity, derived from the word wikt:fecund, generally refers to the ability to reproduce. In biology and demography, fecundity is the potential reproductive capacity of an organism or population, measured by the number of gametes , seed set or asexual propagules.... , small geographic range and recruitment to the fishery. As well as the fishes being overexploited the benthic communities were destroyed by the trawling gear. , Census of Marine Life project CenSeam: a global census of marine life on seamounts

Fish types

Fish types : Details
xxx

Freshwater fisheries

Lakes

Freshwater lakes in the world have an area of 1.5 million square kilometres. Including saline inland seas in this total adds another 1.0 million square kilometres. There are 28 freshwater lakes with an area greater than 5,000 square kilometres, totalling 1.18 million square kilometres or 79 percent of the total.

Rivers

Pollution

Pollution is the introduction of contaminants into an environment that causes instability, disorder, harm or discomfort to the ecosystem i.e. physical systems or living organisms ....
is the introduction of contaminants into an environment. Wild fisheries flourish in oceans, lakes, and rivers, and the introduction of contaminants is an issue of concern, especially as regards plastics, pesticides, heavy metals, and other industrial and agricultural pollutants which do not disintegrate rapidly in the environment. Land run-off and industrial, agricultural, and domestic waste enter rivers and are discharged into the sea. Pollution from ships

Ship pollution

Ship pollution is the pollution of air and water by shipping. It is a problem that has been accelerating as trade has become increasingly globalized, posing an increasing threat to the world?s oceans and waterways as globalization continues....
is also a problem.

Plastic waste

Marine debris

Marine debris, also known as marine litter, is human-created waste that has deliberately or accidentally become afloat in a lake, sea, ocean or waterway....
is human-created waste that ends up floating in the sea. Oceanic debris tends to accumulate at the centre of gyres and coastlines, frequently washing aground where it is known as beach litter. Eighty percent of all known marine debris is plastic - a component that has been rapidly accumulating since the end of World War II. Plastics accumulate because they don't biodegrade

Biodegradation

Biodegradation is the process by which organic compound substances are decomposition by the enzymes produced by living organisms. The term is often used in relation to ecology, waste management and natural environmental environmental remediation ....
as many other substances do; while they will photodegrade

Photodegradation

Photodegradation is degradation of a photodegradable molecule caused by the absorption of photons, particularly those wavelengths found in sunlight, such as infrared radiation, visible light and ultraviolet light....
on exposure to the sun, they do so only under dry conditions, as water

Water (molecule)

File:Blue-water-pool.jpgWater is the most abundant molecule on Earth's surface, constituting about 70% of the Earth's surface in liquid, solid, and gaseous states....
inhibits this process.

Discarded plastic bag

Plastic bag

A plastic bag or pouch is a type of flexible packaging made of thin, flexible, plastic film. Plastic bags are used for containing and transporting foods, produce, powders, ice, chemicals, waste, etc....
s, six pack rings

Six pack rings

Six pack rings or six pack yokes are plastic rings that are used in shipping and packaging of beverage six packs, usually for aluminum cans of soft drinks and beer....
and other forms of plastic waste which finish up in the ocean present dangers to wildlife and fisheries. Aquatic life can be threatened through entanglement, suffocation, and ingestion.

Nurdle

Nurdle

A nurdle, also called a pre-production plastic pellet or plastic resin pellet, is a plastic pellet typically under 5mm in diameter....
s, also known as mermaids' tears, are plastic pellets typically under five millimetres in diameter, and are a major contributor to marine debris. They are used as a raw material in plastics manufacturing, and are thought to enter the natural environment

Natural environment

The natural environment, commonly referred to simply as the environment, is a term that encompasses all life and non-living things occurring nature on Earth or some region thereof....
after accidental spillages. Nurdles are also created through the physical weathering of larger plastic debris. They strongly resemble fish eggs, only instead of finding a nutritious meal, any marine wildlife that ingests them will likely starve, be poisoned and die.

Many animals that live on or in the sea consume

Feeding

Feeding is the process by which organisms, typically animals, obtain food. Terminology often uses either the suffix -vore from Latin vorare, meaning 'to devour', or phagy, from Greek fa?e??, meaning 'to eat'....
flotsam by mistake, as it often looks similar to their natural prey. Plastic debris, when bulky or tangled, is difficult to pass, and may become permanently lodged in the digestive tracts of these animals, blocking the passage of food and causing death through starvation or infection. Tiny floating particles also resemble zooplankton

Zooplankton

Zooplankton are the heterotrophic type of plankton. Plankton are organisms drifting in the Pelagic zone of oceans, seas, and bodies of fresh water....
, which can lead filter feeders to consume them and cause them to enter the ocean food chain

Food chain

Food chains, also called, food networks and/or trophic social networks, describe the eating relationships between species within an ecosystem....
. In samples taken from the North Pacific Gyre in 1999 by the Algalita Marine Research Foundation, the mass of plastic exceeded that of zooplankton by a factor of six. More recently, reports have surfaced that there may now be 30 times more plastic than plankton, the most abundant form of life in the ocean.

Toxic additives used in the manufacture of plastic materials can leech out into their surroundings when exposed to water. Waterborne hydrophobic pollutants collect and magnify on the surface of plastic debris, thus making plastic far more deadly in the ocean than it would be on land. Hydrophobic contaminants are also known to bioaccumulate in fatty tissues, biomagnifying

Biomagnification

Biomagnification, also known as bioamplification or biological magnification, is the increase in concentration of a substance, such as the pesticide DDT, that occurs in a food chain as a consequence of:...
up the food chain and putting great pressure on apex predator

Apex predator

Apex predators are predators that, as adults, are not normally preyed upon in the wild by other large animals in significant parts of their range....
s. Some plastic additives are known to disrupt the endocrine system

Endocrine system

The endocrine system is a system of small organs that involve the release of extracellular signaling molecules known as hormones. The endocrine system is instrumental in regulating metabolism, human development , and tissue and also plays a part in determining Mood ....
when consumed, others can suppress the immune system or decrease reproductive rates.

Toxins

Apart from plastics, there are particular problems with other toxins which do not disintegrate rapidly in the marine environment. Heavy metals are metallic chemical elements that have a relatively high density and are toxic or poisonous at low concentrations. Examples are mercury

Mercury (element)

Mercury , also called quicksilver or hydrargyrum , is a chemical element with the symbol Hg and atomic number 80. A heavy, silvery d-block metal, mercury is one of six elements that are liquid at or near room temperature and pressure....
, lead

Lead

Lead is a main-group Chemical element with symbol Pb and atomic number 82. Lead is a soft, malleable poor metal, also considered to be one of the heavy metal ....
, nickel

Nickel

Nickel is a chemical element, with the chemical symbol Ni and atomic number 28. It is a silvery-white lustrous metal with a slight golden tinge....
, arsenic

Arsenic

Arsenic is a well-known chemical element that has the symbol As and atomic number 33. Arsenic was first documented by Albertus Magnus in 1250....
and cadmium

Cadmium

Cadmium is a chemical element with the symbol Cd and atomic number 48. A relatively abundant , soft, bluish-white, transition metal, cadmium is known to cause cancer and occurs with zinc ores....
. Other persistent toxins are PCBs, DDT

DDT

DDT is one of the best known synthetic pesticides. It is a chemical with a long, unique, and controversial history.First synthesized in 1874, DDT's insecticidal properties were not discovered until 1939....
, pesticide

Pesticide

A pesticide is a substance or mixture of substances used to kill a pest .A pesticide may be a chemical substance, biological agent , antimicrobial, disinfectant or device used against any pest ....
s, furan

Furan

Furan, also known as furane and furfuran, is a Heterocyclic compound organic compound. It is typically derived by the thermal decomposition of pentose-containing materials, cellulosic solids especially pine-wood....
s, dioxin

Dioxin

Polychlorinated dibenzodioxins , or simply dioxins, are a group of polyhalogenated compounds which are significant because they act as environmental pollutants....
s and phenols

Phenols

In organic chemistry, phenols, sometimes called phenolics, are a class of chemical compounds consisting of a hydroxyl Functional group attached to an aromatic hydrocarbon group....
.

Such toxins can accumulate in the tissues of many species of aquatic life in a process called bioaccumulation

Bioaccumulation

Bioaccumulation refers to the accumulation of substances, such as pesticides, or other organic chemicals in an organism. Bioaccumulation occurs when an organism absorbs a toxin at a rate greater than that at which the substance is lost....
. They are also known to accumulate in benthic environments, such as estuaries

Estuary

An estuary is a semi-enclosed coastal body of water with one or more rivers or streams flowing into it, and with a free connection to the open sea....
and bay mud

Bay mud

Bay mud consists of thick deposits of soft, unconsolidated silty clay, which is saturated with water; these soil layers are situated at the bottom of certain estuary, which are normally in temperate regions that have experienced cyclical glacial cycles....
s: a geological record of human activities of the last century.

Some specific examples are

Chinese and Russian industrial pollution such as phenols
Phenols

In organic chemistry, phenols, sometimes called phenolics, are a class of chemical compounds consisting of a hydroxyl Functional group attached to an aromatic hydrocarbon group....
and heavy metals in the Amur River have devastated fish stocks and damaged its estuary
Estuary

An estuary is a semi-enclosed coastal body of water with one or more rivers or streams flowing into it, and with a free connection to the open sea....
soil.

Wabamun Lake
Wabamun Lake

Wabamun Lake is one of the most heavily used lakes in Alberta, Canada. It lies west of Edmonton, Alberta. It is long and narrow, covers and is 6 to 11 metres deep, with somewhat clear water....
in Alberta
Alberta

Alberta is one of Canada Canadian Prairies Provinces and territories of Canada. It became a province on September 1, 1905.Alberta is located in western Canada, bounded by the provinces of British Columbia to the west and Saskatchewan to the east, the Northwest Territories to the north, and the U.S....
, Canada
Canada

Canada is a country occupying most of northern North America, extending from the Atlantic Ocean in the east to the Pacific Ocean in the west and northward into the Arctic Ocean....
, once the best whitefish
Whitefish

Whitefish or white fish may refer to:In fishing terminology:* Whitefish , a fisheries term referring to the flesh of many types of fish...
lake in the area, now has unacceptable levels of heavy metals in its sediment and fish.

Acute and chronic pollution
Pollution

Pollution is the introduction of contaminants into an environment that causes instability, disorder, harm or discomfort to the ecosystem i.e. physical systems or living organisms ....
events have been shown to impact southern California kelp forests, though the intensity of the impact seems to depend on both the nature of the contaminants and duration of exposure.

Due to their high position in the food chain
Food chain

Food chains, also called, food networks and/or trophic social networks, describe the eating relationships between species within an ecosystem....
and the subsequent accumulation
Bioaccumulation

Bioaccumulation refers to the accumulation of substances, such as pesticides, or other organic chemicals in an organism. Bioaccumulation occurs when an organism absorbs a toxin at a rate greater than that at which the substance is lost....
of heavy metals
Heavy metals

A heavy metal is a member of an ill-defined subset of elements that exhibit metallic properties, which would mainly include the transition metals, some metalloids, lanthanides, and actinides....
from their diet, mercury
Mercury (element)

Mercury , also called quicksilver or hydrargyrum , is a chemical element with the symbol Hg and atomic number 80. A heavy, silvery d-block metal, mercury is one of six elements that are liquid at or near room temperature and pressure....
levels can be high in larger species such as bluefin and albacore
Albacore

The albacore, Thunnus alalunga, is a type of tuna in the family Scombridae. This species is also called albacore fish, albacore tuna, longfin, albies, pigfish, tombo ahi, binnaga, Pacific albacore, German bonito , longfin tuna, longfin tunny, or even just tuna....
. As a result, in March 2004 the United States
United States

The United States of America is a Federal government constitutional republic comprising U.S. state and a federal district. The country is situated mostly in central North America, where its Contiguous United States and Washington, D.C., the Capital districts and territories, lie between the Pacific Ocean and Atlantic Oceans, Borders of the U...
FDA
Food and Drug Administration

The U.S. Food and Drug Administration is an Government agency of the United States Department of Health and Human Services and is responsible for regulating and supervising the safety of foods, dietary supplements, Medications, vaccines, Biopharmaceutical, blood transfusion, medical devices, Electromagnetic radiation-emitting devices, veteri...
issued guidelines recommending that pregnant women, nursing mothers and children limit their intake of tuna and other types of predatory fish.

Some shellfish and crabs can survive polluted environments, accumulating heavy metals or toxins in their tissues. For example, mitten crabs have a remarkable ability to survive in highly modified aquatic habitats, including polluted waters. The farming and harvesting of such species needs careful management if they are to be used as a food.

Mining
Mining

Mining is the extraction of value minerals or other geology materials from the earth, usually from an ore body, vein or seam. Materials recovered by mining include base metals, precious metals, iron, uranium, coal, diamonds, limestone, oil shale, Sodium chloride and potash....
has a poor environmental track record. For example, according to the United States Environmental Protection Agency
United States Environmental Protection Agency

The U.S. Environmental Protection Agency is an List of United States federal agencies of the federal government of the United States charged to Regulation of chemicals and protect human health by safeguarding the natural environment: air, water, and land....
, mining has contaminated portions of the headwaters of over 40% of watersheds in the western continental US. Much of this pollution finishes up in the sea.

Heavy metals enter the environment through oil spill
Oil spill

An oil spill is the release of a liquid petroleum hydrocarbon into the environment due to human activity, and is a form of pollution. The term often refers to Marine oil spills, where oil is released into the ocean or coastal waters....
s - such as the Prestige oil spill
Prestige oil spill

The Prestige was an oil tanker whose sinking in 2002 off the Galicia coast caused a large oil spill. The spill polluted thousands of kilometers of coastline and more than one thousand beaches on the Spain and France coast, as well as causing great damage to the local fishing....
on the Galician coast - or from other natural or anthropogenic sources
Pollution

Pollution is the introduction of contaminants into an environment that causes instability, disorder, harm or discomfort to the ecosystem i.e. physical systems or living organisms ....
.

Eutrophication

Eutrophication is an increase in chemical nutrients — compounds containing nitrogen or phosphorus — in an ecosystem, and may occur on land or in water....
is an increase in chemical nutrient

Nutrient

A nutrient is a chemical that an organism needs to live and grow or a substance used in an organism's metabolism which must be taken in from its environment....
s, typically compounds containing nitrogen

Nitrogen

Nitrogen is a chemical element that has the symbol N and atomic number 7 and atomic mass 14.00674?. Elemental nitrogen is a colorless, odorless, tasteless and mostly inert diatomic gas at standard conditions, constituting 78% by volume of Earth's atmosphere....
or phosphorus

Phosphorus

Phosphorus is the chemical element that has the symbol P and atomic number 15. The name comes from the and . A Valency nonmetal of the nitrogen group, phosphorus is commonly found in inorganic phosphate minerals....
, in an ecosystem

Ecosystem

An ecosystem is a natural unit consisting of all plants, animals and micro-organisms in an area functioning together with all of the non-living physical factors of the environment....
. It can result in an increase in the ecosystem's primary productivity (excessive plant growth and decay), and further effects including lack of oxygen and severe reductions in water quality, fish, and other animal populations.

The biggest culprit are rivers that empty into the ocean, and with it the many chemicals used as fertilizers in agriculture as well as waste from livestock

Livestock

Livestock is the term used to refer to a domesticated animal intentionally reared in an agricultural setting to produce things such as food or fibre, or for its labour....
and humans. An excess of oxygen depleting chemicals in the water can lead to hypoxia

Hypoxia (environmental)

Hypoxia or oxygen depletion is a phenomenon that occurs in aquatic environments as oxygen becomes reduced in concentration to a point detrimental to aquatic organisms living in the system....
and the creation of a dead zone

Dead zone (ecology)

Dead zones are hypoxia areas in the world's oceans, the observed incidences of which have been increasing since oceanographers began noting them in the 1970s....
.

Surveys have shown that 54% of lakes in Asia

Asia

Asia is the world's largest and most populous continent. It covers 8.6% of the Earth's total surface area and, with over 4 billion people, it contains more than 60% of the world's current human population....
are eutrophic; in Europe

Europe

Europe is, conventionally, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally divided from Asia to its east by the water divide of the Ural Mountains, the Ural , the Caspian Sea, and by the Caucasus Mountains to the southeast....
, 53%; in North America

North America

North America is the northern continent of the Americas, situated in the Earth's northern hemisphere and almost totally in the western hemisphere....
, 48%; in South America

South America

South America is the southern continent of the Americas, situated entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere....
, 41%; and in Africa

Africa

Africa is the world's second-largest and second most-populous continent, after Asia. At about 30.2 million km? including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area....
, 28%. Estuaries

Estuary

An estuary is a semi-enclosed coastal body of water with one or more rivers or streams flowing into it, and with a free connection to the open sea....
also tend to be naturally eutrophic because land-derived nutrients are concentrated where run-off enters the marine environment in a confined channel. The World Resources Institute

World Resources Institute

The World Resources Institute is an environmental think tank founded in 1982 based in Washington, D.C. in the United States.WRI is an independent, non-partisan and nonprofit organization with a staff of more than 100 scientists, economists, policy experts, business analysts, statistical analysts, mapmakers, and communicators developing and...
has identified 375 hypoxic coastal zones around the world, concentrated in coastal areas in Western Europe, the Eastern and Southern coasts of the US, and East Asia, particularly in Japan. In the ocean, there are frequent red tide

Red tide

"Red tide" is a common name for a phenomenon known as an algal bloom, an event in which estuarine, marine, or fresh water algae accumulate rapidly in the water column....
algae blooms that kill fish and marine mammals and cause respiratory problems in humans and some domestic animals when the blooms reach close to shore.

In addition to land runoff, atmospheric anthropogenic

Anthropogenic

Anthropogenic effects, processes or materials are those that are derived from human activities, as opposed to those occurring in natural environments without human influence....
fixed nitrogen

Nitrogen fixation

Nitrogen fixation is the process by which nitrogen is taken from its relatively inert molecular form in the Earth's atmosphere and converted into nitrogen compounds ....
can enter the open ocean. A study in 2008 found that this could account for around one third of the ocean’s external (non-recycled) nitrogen supply and up to three per cent of the annual new marine biological production. It has been been suggested that accumulating reactive nitrogen in the environment may have consequences as serious as putting carbon dioxide in the atmosphere.

Acidification

The oceans are normally a natural carbon sink, absorbing carbon dioxide from the atmosphere. Because the levels of atmospheric carbon dioxide are increasing, the oceans are becoming more acidic

Ocean acidification

Ocean acidification is the name given to the ongoing decrease in the pH of the Earth's oceans, caused by their uptake of anthropogenic carbon dioxide from the Earth's atmosphere....
. The potential consequences of ocean acidification are not fully understood, but there are concerns that structures made of calcium carbonate may become vulnerable to dissolution, affecting corals and the ability of shellfish to form shells..

A report from NOAA scientists published in the journal Science in May 2008 found that large amounts of relatively acidified water are upwelling to within four miles of the Pacific continental shelf

Continental shelf

The continental shelf is the extended perimeter of each continent and associated coastal plain, and was part of the continent during the glacial periods, but is undersea during Ice age such as the current epoch by relatively shallow seas and Bay....
area of North America. This area is a critical zone where most local marine life lives or is born. While the paper dealt only with areas from Vancouver

Vancouver

Vancouver is a coastal city and major seaport located in the Lower Mainland of southwestern British Columbia, Canada. It is the largest city in British Columbia and the second largest metropolitan area in the Pacific Northwest region....
to northern California, other continental shelf areas may be experiencing similar effects.

Effects of fishing

Habitat destruction

Fishing net

A fishing net or fishnet is a Net that is used for fishing. Fishing nets are meshes usually formed by knotting a relatively thin thread....
s that have been left or lost in the ocean by fishermen are called ghost net

Ghost net

Ghost nets are fishing nets that have been marine debris by fishermen.These nets, often nearly invisible in the dim light, can be left tangled on a rocky reef or drifting in the open sea....
s, and can entangle fish

Fish

A fish is any marine biology vertebrate animal that is typically ectothermic , covered with scale , and equipped with two sets of paired fins and several unpaired fins....
, dolphin

Dolphin

File:Bottlenose_Dolphin_KSC04pd0178.jpgDolphins are marine mammals that are closely related to whales and porpoises. There are almost forty species of dolphin in seventeen genus....
s, sea turtle

Sea turtle

Sea turtles are turtles found in all the world's oceans except the Arctic Ocean. There are seven living species of sea turtles: Flatback Sea Turtle, Green Sea Turtle, Hawksbill turtle, Kemp's Ridley, leatherback sea turtle, Loggerhead Sea Turtle and Olive Ridley Sea Turtle....
s, shark

Shark

Sharks are a type of fish with a full Cartilage skeleton and a highly Streamlines, streaklines and pathlinesd body. They respire with the use of five to seven gill slits....
s, dugong

Dugong

The dugong is a large marine mammal which, together with the manatees, is one of four living species of the order Sirenia. It is the only living representative of the once-diverse family Dugongidae; its closest modern relative, Steller's Sea Cow , was hunted to extinction in the 18th century....
s, crocodile

Crocodile

A crocodile is any species belonging to the family Crocodylidae . The term can also be used more loosely to include all members of the order Crocodilia: i.e....
s, seabird

Seabird

Seabirds are birds that have adaptation to life within the marine environment. While seabirds vary greatly in lifestyle, behavior and physiology, they often exhibit striking convergent evolution, as the same environmental problems and feeding ecological niche have resulted in similar adaptations....
s, crab

Crab

Crabs are Decapoda crustaceans of the infraorder Brachyura, which typically have a very short projecting "tail" , or where the reduced abdomen is entirely hidden under the thorax....
s, and other creatures. Acting as designed, these nets restrict movement, causing starvation, laceration and infection, and—in those that need to return to the surface to breath—suffocation.

Overfishing

Some specific examples of overfishing.

On the east coast of the United States
United States

The United States of America is a Federal government constitutional republic comprising U.S. state and a federal district. The country is situated mostly in central North America, where its Contiguous United States and Washington, D.C., the Capital districts and territories, lie between the Pacific Ocean and Atlantic Oceans, Borders of the U...
, the availability of bay scallops has been greatly diminished by the overfishing of sharks in the area. A variety of sharks have, until recently, fed on rays
Batoidea

Batoidea is a superorder of Chondrichthyes containing more than 500 described species in thirteen families. They are commonly known as rays, but that term is also used specifically for batoids in the order Rajiformes, the "true rays"....
, which are a main predator of bay scallops. With the shark population reduced, in some places almost totally, the rays have been free to dine on scallops to the point of greatly decreasing their numbers.

Chesapeake Bay's
Chesapeake Bay

The Chesapeake Bay is the largest estuary in the United States. It lies off the Atlantic Ocean, surrounded by Maryland and Virginia. The Chesapeake Bay's drainage basin covers in the District of Columbia and parts of six states: New York, Pennsylvania, Delaware, Maryland, Virginia, and West Virginia....
once-flourishing oyster
Oyster

The common name oyster is used for a number of different groups of bivalve mollusks, most of which live in marine habitats or brackish water....
populations historically filtered the estuary's
Estuary

An estuary is a semi-enclosed coastal body of water with one or more rivers or streams flowing into it, and with a free connection to the open sea....
entire water volume of excess nutrients every three or four days. Today that process takes almost a year, and sediment, nutrients, and algae can cause problems in local waters. Oysters filter these pollutants, and either eat them or shape them into small packets that are deposited on the bottom where they are harmless.

The Australian government alleged in 2006 that Japan
Japan

Japan is an island country in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, People's Republic of China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south....
illegally overfished southern bluefin tuna
Southern bluefin tuna

The southern bluefin tuna, Thunnus maccoyii, is a tuna of the family Scombridae found in open southern hemisphere waters of all the worlds oceans mainly between 30?S and 50?S, to nearly 60?S....
by taking 12,000 to 20,000 tonnes per year instead of the their agreed 6,000 tonnes; the value of such overfishing would be as much as USD $2 billion. Such overfishing has resulted in severe damage to stocks. "Japan's huge appetite for tuna will take the most sought-after stocks to the brink of commercial extinction unless fisheries agree on more rigid quotas" stated the WWF
World Wide Fund for Nature

The World Wide Fund for Nature is an Internationalism non-governmental organization for the Conservation biology, Environmental science and Restoration ecology of the environment , formerly named the World Wildlife Fund, which remains its official name in the United States and Canada....
. Japan disputes this figure, but acknowledges that some overfishing has occurred in the past.

Jackson, Jeremy B C et al. (2001) Science 293:629-638.

Loss of biodiversity

Each species

Species

In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring....
in an ecosystem

Ecosystem

An ecosystem is a natural unit consisting of all plants, animals and micro-organisms in an area functioning together with all of the non-living physical factors of the environment....
is affected by the other species in that ecosystem. There are very few single prey-single predator relationships. Most prey are consumed by more than one predator, and most predators have more than one prey. Their relationships are also influenced by other environmental factors. In most cases, if one species is removed from an ecosystem, other species will most likely be affected, up to the point of extinction.

Species biodiversity

Biodiversity

Biodiversity is the variation of life forms within a given ecosystem, biome, or for the entire Earth. Biodiversity is often used as a measure of the health of biological systems....
is a major contributor to the stability of ecosystems. When an organism exploits a wide range of resources, a decrease in biodiversity is less likely to have an impact. However, for an organism which exploit only limited resources, a decrease in biodiversity is more likely to have a strong effect.

Reduction of habitat, hunting and fishing of some species to extinction

Extinction

In biology and ecology, extinction is the death of every member of a species or group of taxon. The moment of extinction is generally considered to be the death of the last individual of that species ....
or near extinction, and pollution tend to tip the balance of biodiversity

Biodiversity

Unified neutral theory of biodiversity

The unified neutral theory of biodiversity and biogeography is a theory and the title of a monograph by ecology Stephen Hubbell. The theory aims to explain the diversity and relative abundance of species in ecological communities, although like other neutral theory of ecology, Hubbell's theory assumes that the differences between members of...
.

Threatened species

The global standard for recording threatened

Threatened species

Threatened species are any species which are vulnerable to extinction in the near future.World Conservation Union is the foremost authority on threatened species, and treats threatened species not as a single category, but as a group of three categories: Vulnerable species, endangered species, and Critically endangered species, depending...
marine species is the IUCN Red List of Threatened Species. This list is the foundation for marine conservation priorities worldwide. A species is listed in the threatened category if it is considered to be critically endangered

Critically endangered

---- Organisms with a conservation status of critically endangered have an extremely high risk of becoming extinct....
, endangered, or vulnerable

Vulnerable

Vulnerable may refer to:*Vulnerability*Vulnerable species* Vulnerable , by Tricky* Vulnerable * Vulnerable ...
. Other categories are near threatened

Near Threatened

Near Threatened is a conservation status assigned to species or lower taxa that may be considered threatened species with extinction in the near future, although it does not currently qualify for the threatened status....
and data deficient

Data Deficient

Data Deficient is a category applied by the IUCN to a species when the available information is not sufficient for a proper assessment of conservation status to be made....
.

Marine

Many marine species are under increasing risk of extinction and marine biodiversity

Biodiversity

Overfishing

Overfishing occurs when fishing activities reduce fish stocks below an acceptable level. This can occur in any body of water from a pond to the oceans....
, bycatch, climate change

Climate change

Climate change is any long-term significant change in the expected patterns of average weather of a specific region over an appropriately significant period of time....
, invasive species

Invasive species

Invasive species is a phrase with several definitions. The first definition expresses the phrase in terms of non-indigenous species that adversely affect the habitats they invade economically, environmentally or ecologically....
and coastal development.

By 2008, the IUCN had assessed about 3,000 marine species. This includes assessments of known species of shark, ray, chimaera, reef-building coral, grouper, marine turtle, seabird, and marine mammal. Almost one-quarter (22%) of these groups have been listed as threatened.

Group	Species Species In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring....	Threatened Threatened species Threatened species are any species which are vulnerable to extinction in the near future.World Conservation Union is the foremost authority on threatened species, and treats threatened species not as a single category, but as a group of three categories: Vulnerable species, endangered species, and Critically endangered species, depending...	Near threatened Near Threatened Near Threatened is a conservation status assigned to species or lower taxa that may be considered threatened species with extinction in the near future, although it does not currently qualify for the threatened status....	Data deficient Data Deficient Data Deficient is a category applied by the IUCN to a species when the available information is not sufficient for a proper assessment of conservation status to be made....
Shark Shark Sharks are a type of fish with a full Cartilage skeleton and a highly Streamlines, streaklines and pathlinesd body. They respire with the use of five to seven gill slits.... s, ray Ray Ray may refer to:Batoidea , a superorder of cartilaginous fishesRajiformes, "True rays" and skatesRadiationRay , idealized narrow beam of light... s, and chimaera Chimaera Chimaeras* are Chondrichthyes in the order Chimaeriformes. They are related to the sharks and batoidea, and are sometimes called ghost sharks, ratfish , or rabbitfishes.... s		17%	13%	47%
Grouper Grouper For other meanings, see Grouper .Groupers are fish of any of a number of genus in the subfamily Epinephelinae of the family Serranidae, in the order Perciformes.... s		12%	14%	30%
Reef-building corals Coral Corals are marine organisms from the class Anthozoa and exist as small sea anemone?like polyps, typically in colonies of many identical individuals....	845	27%	20%	17%
Marine mammal Marine mammal Marine mammals are a diverse group of roughly 120 species of mammal that are primarily ocean-dwelling or depend on the ocean for food. They include the cetaceans , the sirenians , the pinnipeds , and several otters .... s		25%
Seabird Seabird Seabirds are birds that have adaptation to life within the marine environment. While seabirds vary greatly in lifestyle, behavior and physiology, they often exhibit striking convergent evolution, as the same environmental problems and feeding ecological niche have resulted in similar adaptations.... s		27%
Marine turtles	7	86%

Sharks, rays, and chimaeras: are deep water pelagic species, which makes them difficult to study in the wild. Not a lot is known about their ecology and population status. Much of what is currently known is from their capture in nets
Fishing net

A fishing net or fishnet is a Net that is used for fishing. Fishing nets are meshes usually formed by knotting a relatively thin thread....
from both targeted and accidental catch. Many of these slow growing species are not recovering from overfishing by shark fisheries around the world.

Groupers: Major threats are overfishing, particularly the uncontrolled fishing of small juveniles and spawning adults.

Coral reef
Coral reef

Coral reefs are aragonite structures produced by living organisms. In most reefs the predominant organisms are colonial cnidarian that secrete an exoskeleton of calcium carbonate....
s: The primary threats to coral
Coral

Corals are marine organisms from the class Anthozoa and exist as small sea anemone?like polyps, typically in colonies of many identical individuals....
s are bleaching and disease which has been linked to an increase in sea temperatures. Other threats include coastal development, coral extraction, sedimentation and pollution. The coral triangle
Coral Triangle

The Coral Triangle is a geographical term referring to the waters of Indonesia, Malaysia, Papua New Guinea, Philippines, Solomon Islands and Timor-Leste with an abundance of coral reef....
(Indo-Malay-Philippine archipelago) region has the highest number of reef-building coral species in threatened category as well as the highest coral species diversity. The loss of coral reef ecosystems will have devastating effects on many marine species, as well as on people that depend on reef resources for their livelihoods.

Marine mammals: include whale
Whale

Whales are marine mammals of order Cetacea which are neither dolphinsmembers, in other words, of the families Oceanic dolphin or River dolphinnor porpoises....
s, dolphin
Dolphin

File:Bottlenose_Dolphin_KSC04pd0178.jpgDolphins are marine mammals that are closely related to whales and porpoises. There are almost forty species of dolphin in seventeen genus....
s, porpoise
Porpoise

Porpoises are small cetaceans of the family Phocoenidae; they are related to whales and dolphins. They are distinct from dolphins, although the word "porpoise" has been used to refer to any small dolphin, especially by sailors and fishermen....
s, seal
Seal

Seal may refer to:...
s, sea lion
Sea Lion

For other uses of the term "sea lion", see Sea lion .Sea lions are any of seven species in six genera of modern pinnipeds including one extinct ....
s, walrus
Walrus

The walrus is a large pinniped marine mammal with a discontinuous circumpolar distribution in the Arctic Ocean and sub-Arctic seas of the Northern Hemisphere....
es, sea otter
Sea Otter

The sea otter is a marine mammal native to the coasts of the northern and eastern Pacific Ocean. Adult sea otters typically weigh between 14 and 45 Kilogram , making them the heaviest members of the Mustelidae, but among the smallest marine mammals....
, marine otter
Marine Otter

Marine Otters are rare and poorly-known marine mammals of the weasel family . They are the most exclusively marine species of the otters of South America, and rarely even venture into freshwater or estuarine habitats....
, manatee
Manatee

Manatees are large, fully aquatic marine mammals sometimes known as sea cows. The name manat? comes from the Ta?no, a pre-Columbian people of the Caribbean, meaning "breast"....
s, dugong
Dugong

The dugong is a large marine mammal which, together with the manatees, is one of four living species of the order Sirenia. It is the only living representative of the once-diverse family Dugongidae; its closest modern relative, Steller's Sea Cow , was hunted to extinction in the 18th century....
and the polar bear
Polar Bear

The polar bear is a bear native to the Arctic Ocean and its surrounding seas. The world's largest carnivore found on land, and shares the title of largest land predator with the Kodiak Bear, an adult male weighs around , while an adult female is about half that size....
. Major threats include entanglement in ghost net
Ghost net

Ghost nets are fishing nets that have been marine debris by fishermen.These nets, often nearly invisible in the dim light, can be left tangled on a rocky reef or drifting in the open sea....
s, targeted harvesting, noise pollution from military and seismic sonar, and boat strikes. Other threats are water pollution, habitat loss from coastal development, loss of food sources due to the collapse of fisheries, and climate change.

Seabirds: Major threats include longline fisheries and gillnet
Gillnet

Gillnetting is a common fishing method used by fishing industry fishermen of all the oceans and in some freshwater and estuary areas. Because gillnets can be so effective their use is closely monitored and regulated by fisheries management and enforcement agencies....
s, oil spill
Oil spill

An oil spill is the release of a liquid petroleum hydrocarbon into the environment due to human activity, and is a form of pollution. The term often refers to Marine oil spills, where oil is released into the ocean or coastal waters....
s, and predation by rodents and cats in their breeding grounds. Other threats are habitat loss and degradation from coastal development, logging and pollution.

Marine turtles: Marine turtles lay their eggs on beaches, and are subject to threats such as coastal development, sand mining, and predators, including humans who collect their eggs for food in many parts of the world. At sea, marine turtles can be targeted by small scale subsistence fisheries
Artisan fishing

Artisan fishing is a term sometimes used to describe small scale commercial fishing or subsistence fishing practises. The term particularly applies to coastal or island ethnic groups using traditional Fishing techniques such as Fishing rod and Fishing tackle, Bow fishing and harpoons, Cast net and drag nets, and maybe Coble....
, or become bycatch during longline
Longline

Longline can mean:-* Longline fishing* Long line * Long line * Aerial crane, i.e. using a helicopter to lift a heavy object...
and trawling
Trawling

Trawling is a method of fishing that involves pulling a large fishing net through the water behind one or more boats. The net that is used for trawling is called a trawl....
activities, or become entangled in ghost net
Ghost net

Ghost nets are fishing nets that have been marine debris by fishermen.These nets, often nearly invisible in the dim light, can be left tangled on a rocky reef or drifting in the open sea....
s or struck by boats.

An ambitious project, called the Global Marine Species Assessment, is under way to make IUCN Red List assessments for another 17,000 marine species by 2012. Groups targeted include the approximately 15,000 known marine fishes, and important habitat-forming primary producers such mangrove

Mangrove

Mangroves are trees and shrubs that grow in saline water coastal habitats in the tropics and subtropics. The word is used in at least three senses: most broadly to refer to the habitat and entire plant assemblage or mangal, for which the terms mangrove swamp and mangrove forest are also used, to refer to all trees and...
s, seagrass

Seagrass

Seagrasses are flowering plants from one of four plant families , which grow in marine , fully-saline water environments....
es, certain seaweed

Seaweed

Seaweed is a loose colloquial term encompassing macroscopic, multicellular, benthos ocean algae. The term includes some members of the rhodophyta, phycophyta and green algae....
s and the remaining coral

Coral

Corals are marine organisms from the class Anthozoa and exist as small sea anemone?like polyps, typically in colonies of many identical individuals....
s; and important invertebrate groups including molluscs and echinoderm

Echinoderm

Echinoderms are a Phylum of Marine animals . Echinoderms are found at every ocean depth, from the intertidal zone to the abyssal zone.Aside from the problematic Arkarua, the first definitive members of the phylum appeared near the start of the Cambrian period....
s.

Freshwater

Freshwater fisheries have a disproportionately high diversity of species compared to other ecosystems. Although freshwater habitats cover less than 1% of the world’s surface, they provide a home for over 25% of known vertebrates, more than 126,000 known animal species, about 24,800 species of freshwater fish

Freshwater fish

Fresh water fish are fish that spend some or all of their lives in fresh water, such as rivers and lakes, with a salinity of less than 0.05%....
, molluscs, crab

Crab

Dragonfly

A dragonfly is a type of insect belonging to the order Odonata, the suborder Epiprocta or, in the strict sense, the infraorder Anisoptera....
, and about 2,600 macrophyte

Macrophyte

A macrophyte is an aquatic plant that grows in or near water and is either emergent, submergent, or floating. In lakes macrophytes provide cover for fish and Substrate for Aquatic animal invertebrates, produce oxygen, and act as food for some fish and wildlife....
s.

Continuing industrial and agricultural developments place huge strain on these freshwater systems. Waters are polluted or extracted at high levels, wetlands are drained, rivers channelled, forests deforestated leading to sedimentation, invasive species are introduced, and over-harvesting occurs.

In the 2008 IUCN Red List, about 6,000 or 22% of the known freshwater species have been assessed at a global scale, leaving about 21,000 species still to be assessed. This makes clear that, worldwide, freshwater species are highly threatened, possibly more so than species in marine fisheries. However, a significant proportion of freshwater species are listed as data deficient

Data Deficient

Data Deficient is a category applied by the IUCN to a species when the available information is not sufficient for a proper assessment of conservation status to be made....
, and more field surveys are needed.

Fisheries management

A recent paper published by the National Academy of Sciences

United States National Academy of Sciences

The National Academy of Sciences is a corporation in the United States whose members serve pro bono as "advisers to the nation on science, engineering, and medicine."...
of the USA warns that: "Synergistic effects of habitat destruction, overfishing, introduced species, warming, acidification, toxins, and massive runoff of nutrients are transforming once complex ecosystems like coral reefs and kelp forests into monotonous level bottoms, transforming clear and productive coastal seas into anoxic dead zones, and transforming complex food webs topped by big animals into simplified, microbially dominated ecosystems with boom and bust cycles of toxic dinoflagellate blooms, jellyfish, and disease".

External links

International Nitrogen Initiative:
(2000) World Resources Institute
World Resources Institute

The World Resources Institute is an environmental think tank founded in 1982 based in Washington, D.C. in the United States.WRI is an independent, non-partisan and nonprofit organization with a staff of more than 100 scientists, economists, policy experts, business analysts, statistical analysts, mapmakers, and communicators developing and...
.
NOAA:

Wild fisheries of the world

Marine fisheries

Topography

Ocean currents

Gyres and upwelling

Biomass

Habitats

Coastal waters

Continental shelves

Coral reefs

Open sea

Seamounts

Fish types

Freshwater fisheries

Lakes

Rivers

Pollution

Plastic waste

Toxins

Eutrophication

Acidification

Effects of fishing

Habitat destruction

Overfishing

Loss of biodiversity

Threatened species

Marine

Freshwater

Fisheries management

See also

External links