Silver trout | |
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Scientific classification ![]() | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Actinopterygii |
Order: | Salmoniformes |
Family: | Salmonidae |
Genus: | Salvelinus |
Subgenus: | Baione |
Species: | †S. agassizii |
Binomial name | |
†Salvelinus agassizii (Garman, 1885) | |
Synonyms | |
Salvelinus fontinalis agassizii |
The silver trout (Salvelinus agassizii) is an extinct char species or subspecies that inhabited a few waters in New Hampshire in the United States prior to 1939, when a biological survey conducted on the Connecticut watershed by the New Hampshire Fish and Game Department found none.
The silver trout was often a foot long and was said to actually be olive green in color. In the lakes silver trout inhabited, large quantities of the species appeared in October to spawn.
To formally describe the species and prevent local fishermen from overharvesting in the absence of bag limits, specimens were sent to Harvard and the U.S. National Museum for identification, where the fish was first described as a form of lake trout (Salvelinus namaycush), and later as a variety of brook trout (Salvelinus fontinalis). The silver trout was described as Salmo agassizii in 1885. W.C.Kendall, who published a famous monograph on New England chars in 1914, in turn concluded that the silver trout was related to the Arctic char (Salvelinus alpinus).
Re-examining the 13 silver trout specimens in the U.S. National Museum by matching the markings on the dorsal fin and tail, the numbers of vertebrae, and the array of pelvic fin rays and between different species, Robert J. Behnke concluded that the silver trout was most closely related to the brook trout, while the divergence was still concluded to be enough to place it outside of typical S. fontinalis. Behnke concluded the silver trout evolved from brook trout ancestors in New England lakes with deep, cold, clear, well-oxygenated depths as a planctivorous fish. [3]
The silver trout was an exceedingly rare fish, having become trapped by changed drainage systems in two New Hampshire lakes (Dublin/Monadnock Pond and Christine Lake in Stark) that were left as successors of Lake Hitchcock, a very large glacial lake that persisted for 4,000 years where the silver trout probably evolved from brook trout. [3] In the deep waters of these lakes, cut off from other species, the silver trout had no natural predators.[ citation needed ]
By the late 19th century, as each lake developed its own steady summer tourism, recreational fishermen who sought to increase their catches began to introduce new fish species, and these eventually overwhelmed the native silver trout. Yellow perch, which eat trout eggs, and lake trout, which hold the same ecological niche, as well as eat and hybridize with other char species, were particularly devastating. Other species were also introduced that have proved to be devastating to native trout species in other waters, the rainbow trout, brown trout, Atlantic salmon, and rainbow smelt. [3] The last six specimens were collected in 1930.
While the silver trout is most likely lost, success stories like the Pyramid Lake Lahontan cutthroat trout and the Sunapee golden trout exist, and there may still be hope for the silver trout.
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.
The lake trout is a freshwater char living mainly in lakes in northern North America. Other names for it include mackinaw, namaycush,lake char (or charr), touladi, togue, and grey trout. In Lake Superior, it can also be variously known as siscowet, paperbelly and lean. The lake trout is prized both as a game fish and as a food fish. Those caught with dark coloration may be called mud hens.
The brown trout is a species of salmonid ray-finned fish and the most widely distributed species of the genus Salmo, endemic to most of Europe, West Asia and parts of North Africa, and has been widely introduced globally as a game fish, even becoming one of the world's worst invasive species outside of its native range.
The bull trout is a char of the family Salmonidae native to northwestern North America. Historically, S. confluentus has been known as the "Dolly Varden", but was reclassified as a separate species in 1980. Populations of bull trout in the lower 48 states are listed as threatened under the U.S. Endangered Species Act, and bull trout overall are listed as vulnerable to extinction on the IUCN Red List of Threatened Species. The Saskatchewan-Nelson Rivers population in Alberta, Canada is listed as threatened under the Species at Risk Act.
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 brook trout is a species of freshwater fish in the char genus Salvelinus of the salmon family Salmonidae native to Eastern North America in the United States and Canada. Two ecological forms of brook trout have been recognized by the US Forest Service. One ecological form is short-lived potamodromous populations in Lake Superior known as coaster trout or coasters. The second ecological form is the long-living predaceous anadromous populations which are found in northern lakes and coastal rivers from Long Island to Hudson Bay, which are referred to as salters. In parts of its range, it is also known as the eastern brook trout, speckled trout, brook char, squaretail, brookie, or mud trout, among others. Adult coaster brook trout are capable of reaching sizes over 2 feet in length and weigh up to 6.8 kg (15 lb), whereas adult salters average between 6 and 15 inches in length and weigh between 0.5 and 2.3 kg. The brook trout is characterized by its distinctive olive-green body with yellow and blue-rimmed red spots, white and black edged orange fins, and dorsal vermiculation. The diet of the brook trout is restrictive to the season and location of the fish, but will typically consist of terrestrial and aquatic insects, fry, crustaceans, zooplankton, and worms.
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.
The Arctic char or Arctic charr is a cold-water fish in the family Salmonidae, native to alpine lakes, as well as Arctic and subarctic coastal waters in the Holarctic.
Sea trout is the common name usually applied to anadromous (sea-run) forms of brown trout, and is often referred to as Salmo trutta morpha trutta. Other names for anadromous brown trout are bull trout, sewin (Wales), peel or peal, mort, finnock (Scotland), white trout (Ireland), Dollaghan and salmon trout (culinary).
The Dolly Varden trout is a species of salmonid ray-finned fish native to cold-water tributaries of the Pacific Ocean in Asia and North America. Despite the name "trout", it belongs to the genus Salvelinus (chars), which includes 51 recognized species, the most prominent being the brook, lake and bull trout as well as the Arctic char. Although many populations are semi-anadromous, riverine and lacustrine populations occur throughout its range. It is considered by taxonomists as part of the Salvelinus alpinus complex, as many populations of bull trout, Dolly Varden trout and Arctic char overlap.
Salvelinus is a genus of salmonid fish often called char or charr; some species are called "trout". Salvelinus is a member of the subfamily Salmoninae within the family Salmonidae. The genus has a northern circumpolar distribution, and most of its members are typically cold-water fish that primarily inhabit fresh waters. Many species also migrate to the sea.
The aurora trout, Salvelinus fontinalis timagamiensis, is a variant or subspecies of the brook trout native to two lakes in the Temagami District of Ontario, Canada. The existence of the fish was brought to the attention of the angling world by four American anglers who were taken by Archie King of Latchford, Ontario, into Ontario's Lady Evelyn River system in 1923. Recognizing the fish as different or unique, the anglers took a specimen back to the Carnegie Museum in Pittsburgh, in the United States, where Dr. Arthur W. Henn was asked to identify the fish. He wrote about the fish in 1925 wherein he and Rinckenbach identified it as a distinct species, Salvelinus timagamiensis, but since a seminal re-examination of the material by Sale in 1967, taxonomists now agree the fish is, in a fact, at most a subspecies of the brook trout, named Salvelinus fontinalis timagamiensis. Genetic data has not yet supported its taxonomic distinction.
Lahontan cutthroat trout is the largest subspecies of cutthroat trout, and the state fish of Nevada. It is one of three subspecies of cutthroat trout that are listed as federally threatened.
The splake or slake is a hybrid of two fish species resulting from the crossing of a male brook trout and a female lake trout. The name itself is a portmanteau of speckled trout and lake trout, and may have been used to describe such hybrids as early as the 1880s. Hybrids of the male lake trout with the female brook trout have also been produced, but are not as successful.
The brook stickleback is a small freshwater fish that is distributed across the US and Canada. It grows to a length of about 2 inches. It occupies the northern part of the eastern United States, as well as the southern half of Canada. Small populations are scattered throughout the Mississippi-Great Lakes basin extending to Colorado, New Mexico, Kentucky, Tennessee, etc., though some of these areas are not native to the species. This small fish inhabits clear, cool streams and lakes. They eat small invertebrates, algae, insect larvae, and occasionally their own eggs. They are also preyed upon by smallmouth bass and northern pike. Feeding time is usually dawn and sunset. The brook stickleback does have active competition mostly from minnows, but feeding times are different, along with diet. Spawning occurs in midsummer. Males secure a territory, build a nest, and mate with females. Males provide protection for the eggs, ward off predators, and usually die later in the season. This is considered an annual species. The nests are built out of aquatic grasses. Though the brook stickleback is not considered a threatened species, deforesting and changing waters are altering ecosystems of the species. Harvesting of trees around riparian environments is having a large effect of the stream ecosystem where the brook stickleback resides.
Salvelinus umbla, also known as lake char, is a species of char found in certain lakes of the region of the Alps in Europe.
The Sunapee trout, also called blueback trout, Sunapee Golden trout, or Quebec red trout, is a putative subspecies of Arctic char native to northeastern New England in the United States, as well as Québec and New Brunswick in Canada, with introduced populations in Idaho.