The authors recommended immediate drastic cutbacks in fish catches and [1] Particularly imperiled were sharks, Atlantic cod, Bluefin tuna, and Pacific sardines. On May 15, 2003, the journal Nature reported that all large oceanic fish species worldwide had been so systematically over caught that fewer than 10% of 1950 levels remained. Overfishing is a threat to many species of fish. The annual yield from all fisheries worldwide is about 100 million tonnes.
Catching fish for the purpose of food or sport is known as fishing. Some species of fish have been specially bred to be kept and displayed in an aquarium, and can survive in the home environment. However, hyper-saline lakes like the Great Salt Lake do not support fishes. // Fish ecology Fish can be found in almost all large bodies of water in salt, brackish or fresh water, at depths from just below the surface to several thousand meters.
Endothermy, though metabolically costly, is thought to provide advantages such as increased contractile force of muscles, higher rates of central nervous system processing, and higher rates of digestion. See also gigantothermy. The degree of endothermy varies from the billfish, which warm only their eyes and brain, to bluefin tuna and porbeagle sharks who maintain body temperatures elevated in excess of 20 °C above ambient water temperatures. All sharks in the family Lamnidae – shortfin mako, long fin mako, white, porbeagle, and salmon shark – are known to have the capacity for endothermy, and evidence suggests the trait exists in family Alopiidae (thresher sharks). Endothermic teleosts (bony fishes) are all in the suborder Scombroidei and include the billfishes, tunas, and one species of "primitive" mackerel (Gasterochisma melampus).
Some species of fish maintain elevated body temperatures to varying degrees. However, hyper-saline lakes like the Great Salt Lake do not support fishes. // Fish ecology Fish can be found in almost all large bodies of water in salt, brackish or fresh water, at depths from just below the surface to several thousand meters. Endothermy, though metabolically costly, is thought to provide advantages such as increased contractile force of muscles, higher rates of central nervous system processing, and higher rates of central nervous system processing, and higher rates of central nervous system processing, and higher rates of digestion.
See also gigantothermy. The degree of endothermy varies from the billfish, which warm only their eyes and brain, to bluefin tuna and porbeagle sharks who maintain body temperatures elevated in excess of 20 °C above ambient water temperatures. All sharks in the family Lamnidae – shortfin mako, long fin mako, white, porbeagle, and salmon shark – are known to have the capacity for endothermy, and evidence suggests the trait exists in family Alopiidae (thresher sharks). Endothermic teleosts (bony fishes) are all in the suborder Scombroidei and include the billfishes, tunas, and one species of "primitive" mackerel (Gasterochisma melampus).
Atlantic herring, Clupea harengus: the most abundant species of fish maintain elevated body temperatures to varying degrees. For other uses, see Fish (disambiguation).
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