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Many species of salmon are anadromous and can migrate long distances up rivers to spawn Allowing fish and other migratory animals to travel the rivers can help maintain healthy fish populations. Fish migration is mass relocation by fish from one area or body of water to another. Many types of fish migrate on a regular basis, on time scales ...
Vulnerable (VU) species are considered to be facing a high risk of extinction in the wild. In September 2016, the International Union for Conservation of Nature (IUCN) listed 1245 vulnerable fish species. [1] Of all evaluated fish species, 8.1% are listed as vulnerable. The IUCN also lists eight fish subspecies as vulnerable.
Highly migratory species – a term which has its origins in the United Nations Convention on the Law of the Sea. It refers to fish species which undertake ocean migrations and also have wide geographic distributions. It usually denotes tuna and tuna-like species, shark, marlins and swordfish. See also transboundary stocks and straddling stocks.
Fishes are a paraphyletic group and for this reason, the class Pisces seen in older reference works is no longer used in formal taxonomy.Traditional classification divides fish into three extant classes (Agnatha, Chondrichthyes, and Osteichthyes), and with extinct forms sometimes classified within those groups, sometimes as their own classes: [1]
The fourth edition was the first to incorporate the wide use of DNA analysis, revising many earlier classifications. The first edition appeared in 1976, the second in 1984, the third in 1994 ( John Wiley & Sons , ISBN 0-471-54713-1 ), the fourth in March 2006 ( ISBN 0-471-25031-7 ), and the fifth in April 2016 ( ISBN 9781118342336 ).
A wild fishery is a natural body of water with a sizeable free-ranging fish or other aquatic animal (crustaceans and molluscs) population that can be harvested for its commercial value. Wild fisheries can be marine or lacustrine/riverine , and rely heavily on the carrying capacity of the local aquatic ecosystem.
Common names of fish can refer to a single species; to an entire group of species, such as a genus or family; or to multiple unrelated species or groups. Ambiguous common names are accompanied by their possible meanings. Scientific names for individual species and higher taxa are included in parentheses.
A few hundred species migrate long distances, in some cases of thousands of kilometres. About 120 species of fish, including several species of salmon, migrate between saltwater and freshwater (they are 'diadromous'). [23] [24] Forage fish such as herring and capelin migrate around substantial parts of the North Atlantic ocean.