Mexican golden trout | |
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Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Actinopterygii |
Order: | Salmoniformes |
Family: | Salmonidae |
Genus: | Oncorhynchus |
Species: | O. chrysogaster |
Binomial name | |
Oncorhynchus chrysogaster | |
Synonyms [2] | |
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The Mexican golden trout (Oncorhynchus chrysogaster) is a species of fish in the family Salmonidae. The species is endemic to high-elevation headwaters of the Fuerte River, Sinaloa River, and Culiacán River drainages in the Sierra Madre Occidental in Mexico.
In 1936, Paul Needham, a fisheries biologist with the U.S. Bureau of Fisheries began a series of explorations (1936, 1937 and 1938) into the Rio Santo Domingo drainage in Baja California seeking to bring back live specimens of the Baja rainbow trout as hatchery stock and further study. Although live specimens reached U.S. hatcheries, none ever survived to spawn. In 1952, 1955 and 1956 Needham again explored the Sierra Madre Occidental tributaries of the Gulf of California. Needham's explorations led to the publication of Rainbow Trout of Mexico and California (1959) with coauthor Richard Gard. It contains the first full color drawing of the Mexican golden trout. In 1964, Needham and Gard's proposed binomial name Salmo chrysogaster was accepted as the scientific name for a new species of trout, the Mexican golden trout. The specific name chrysogaster is derived from the Greek for "golden belly". [3] In 1989, morphological and genetic studies indicated trout of the Pacific basin were genetically closer to Pacific salmon (Oncorhynchus species) than to the Salmos —brown trout (S. trutta) or Atlantic salmon (S. salar)—of the Atlantic basin. [4] Thus, in 1989, taxonomic authorities moved the rainbow, cutthroat and other Pacific basin trout, including the Mexican golden trout, into the genus Oncorhynchus. [5]
The Mexican golden trout is sexually dimorphic; males can easily be identified from females due to their much longer jaws or kype. Mexican golden trout are brightly colored with blue parr marks on both males and females along the side of the body. Purple scaling is visible along the lateral line. Both sexes also have bright golden-yellow belly coloration. The top of the fish and the tailfin are covered in small black spots with much larger spotting on the dorsal fin. The pectoral fins, pelvic fin and anal fin are light orange in color with white tips. Due to their harsh and small stream habitat the Mexican golden trout remains small even when fully grown. Adults rarely reach over a foot long with the maximum size probably being 10 inches (25 cm). Overall body shape and fin placement are nearly identical to those of rainbow trout. Juvenile banding ("parr marks") usually remains distinct throughout the fish's life.
Mexican golden trout have an extremely limited range, being found only in the pristine high-elevation headwaters of the Fuerte River, Sinaloa River, and Culiacán River drainages in the Sierra Madre Occidental. This fish is highly restricted, and only known from 15 localities: one in the Sinaloa, four in the Culiacan, and ten in the Fuerte.
Mexican golden trout are limited to small streams created by small cienegas (spring-fed marshes) above 5,000 feet (1,500 m). The surrounding landscape is dominated by deep canyons, scrub forest, evergreens and hardwoods.
Due to their small range and highly sensitive, isolated habitat, Mexican golden trout are considered vulnerable. The biggest threats are human development and the possibility of competition/interbreeding with introduced rainbow trout (Oncorhynchus mykiss). [6] [7] This trout is also an example of the negative effects of habitat abuse and destruction. The primary use for the Mexican golden trout is as food by the local indigenous people. Some of the local people use dynamite to stun the fish and collect them as they float to the top of the water. [7] This is especially harmful to the golden trout populations because of the mass harvest. Sanitation practices in the region where the golden trout is found is minimal, so much of its home water is polluted with residential sewage and trash.[ citation needed ] What is happening now in Mexican golden trout water is similar to what happened to so many other North American trout waters in the 19th and early 20th centuries, as far as decline in populations is concerned.[ citation needed ]
The scenic area and rugged mountainous landscape have started a budding tourism industry for this area. Being able to conserve and promote the sustainable harvesting of these native trout can help the people of the area as well as the Mexican golden trout. Setting up regulations on the harvesting of the fish and restrictions on polluting the head waters these fish inhabit would greatly improve the region. In Arizona and New Mexico, 512 million dollars was spent on trips and equipment for fishing.[ when? ] This revenue could be a major contributor to helping the area grow and being able to conserve the local environment from destruction.
Salmon is the common name for several commercially important species of euryhaline ray-finned fish from the genera Salmo and Oncorhynchus of the family Salmonidae, native to tributaries of the North Atlantic (Salmo) and North Pacific (Oncorhynchus) basins. Other closely related fish in the same family include trout, char, grayling, whitefish, lenok and taimen, all coldwater fish of the subarctic and cooler temperate regions with some sporadic endorheic populations in Central Asia.
Trout is a generic common name for numerous species of carnivorous freshwater ray-finned fishes belonging to the genera Oncorhynchus, Salmo and Salvelinus, all of which are members of the subfamily Salmoninae in the family Salmonidae. The word trout is also used for some similar-shaped but non-salmonid fish, such as the spotted seatrout/speckled trout.
Salmonidae is a family of ray-finned fish that constitutes the only currently extant family in the order Salmoniformes, consisting of 11 extant genera and over 200 species collectively known as "salmonids" or "salmonoids". The family includes salmon, trout, char, graylings, freshwater whitefishes, taimens and lenoks, all coldwater mid-level predatory fish that inhabit the subarctic and cool temperate waters of the Northern Hemisphere. The Atlantic salmon, whose Latin name became that of its genus Salmo, is also the eponym of the family and order names.
The rainbow trout is a species of trout native to cold-water tributaries of the Pacific Ocean in Asia and North America. The steelhead is an anadromous (sea-run) form of the coastal rainbow trout(O. m. irideus) or Columbia River redband trout (O. m. gairdneri) that usually returns to freshwater to spawn after living two to three years in the ocean. Freshwater forms that have been introduced into the Great Lakes and migrate into tributaries to spawn are also called steelhead.
The cutthroat trout(Oncorhynchus clarkii) is a fish species of the family Salmonidae native to cold-water tributaries of the Pacific Ocean, Rocky Mountains, and Great Basin in North America. As a member of the genus Oncorhynchus, it is one of the Pacific trout, a group that includes the widely distributed rainbow trout. Cutthroat trout are popular gamefish, especially among anglers who enjoy fly fishing. The common name "cutthroat" refers to the distinctive red coloration on the underside of the lower jaw. The specific name clarkii was given to honor explorer William Clark, coleader of the Lewis and Clark Expedition.
The Californiagolden trout (Oncorhynchus aguabonita or Oncorhynchus mykiss aguabonita) is a species of trout native to California. The golden trout is normally found in the Golden Trout Creek, Volcano Creek, and the South Fork Kern River. The Golden trout is the official freshwater state fish of California since 1947.
Oncorhynchus is a genus of ray-finned fish in the subfamily Salmoninae of the family Salmonidae, native to coldwater tributaries of the North Pacific basin. The genus contains twelve extant species, namely six species of Pacific salmon and six species of Pacific trout, all of which are migratory mid-level predatory fish that display natal homing and semelparity.
The yellowfin cutthroat trout is an extinct subspecies or variety of the cutthroat trout, a North American freshwater fish.
Redband trout are a group of three recognized subspecies of rainbow trout. They occur in three distinct regions in Pacific basin tributaries and endorheic basins in the western United States. The three subspecies are the Columbia River redband trout, the McCloud River redband trout and the Great Basin redband trout.
The westslope cutthroat trout, also known as the black-spotted trout, common cutthroat trout and red-throated trout is a subspecies of the cutthroat trout and is a freshwater fish in the salmon family of order Salmoniformes. The cutthroat is the Montana state fish. This subspecies is a species of concern in its Montana and British Columbia ranges and is considered threatened in its native range in Alberta.
The coastal cutthroat trout, also known as the sea-run cutthroat trout, blue-back trout or harvest trout, is one of the several subspecies of cutthroat trout found in Western North America. The coastal cutthroat trout occurs in four distinct forms. A semi-anadromous or sea-run form is the most well known. Freshwater forms occur in both large and small rivers and streams and lake environments. The native range of the coastal cutthroat trout extends south from the southern coastline of the Kenai Peninsula in Alaska to the Eel River in Northern California. Coastal cutthroat trout are resident in tributary streams and rivers of the Pacific basin and are rarely found more than 100 miles (160 km) from the ocean.
The Baja California rainbow trout or San Pedro Martir trout or Nelson's trout is a localized subspecies of the rainbow trout, a freshwater fish in the family Salmonidae.
The Sheepheaven Creek redband trout is a local Californian variety of the rainbow trout, a freshwater fish in the family Salmonidae. It is considered either a distinct western form of the McCloud River redband trout, or a subspecies of its own, which has not been scientifically named and described yet. It is native to Sheepheaven Creek, Siskiyou County, California, United States. It has been transplanted into Swamp Creek in 1972 and 1974 and into Trout Creek in 1977. They can now be found in both locations. Sheepheaven Creek redband are found to be the most distinct anatomically among all other western North American trout groups, and therefore has been suggested to merit recognition as a new subspecies. A key diagnostic character is that they have the fewest gill rakers of any western trout.
The Kern River rainbow trout is a localized subspecies of the rainbow trout, a variety of fish in the family Salmonidae. It is found in a short section of the main stem of the Kern River and several tributaries in the southern Sierra Nevada in California. The Kern River rainbow trout is a "Species of Special Concern" in the state of California due to habitat loss and hybridization with other native and non-native trout in their range.
Mexican native trout —Mexican rainbow trout, sometimes Baja rainbow trout and Mexican golden trout —occur in the Pacific Ocean tributaries of the Baja California peninsula and in the Sierra Madre Occidental of northwestern Mexico as far south as Victoria de Durango in the state of Durango. Many forms of the Mexican rainbow trout, subspecies of the rainbow trout, have been described. The Mexican golden trout is a recognized species.
The Little Kern golden trout is a brightly colored subspecies of rainbow trout native to the main stem and tributaries of the Little Kern River in Tulare County, California. Together with the California golden trout and the Kern River rainbow trout, the Little Kern golden trout forms what is sometimes referred to as the "golden trout complex" of the Kern River basin.