Silver trout

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The name "silver trout" is also sometimes used for rainbow trout.

Silver trout
Salvelinus agassizi.jpg
Status iucn2.3 EX.svg
Extinct  (1939)  (IUCN 2.3) [1]
Scientific classification Red Pencil Icon.png
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 variety that inhabited a few waters in New Hampshire prior to 1939, when a biological survey conducted on the Connecticut watershed by the New Hampshire Fish and Game Department found none.

Contents

Description

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.

Systematic position

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. [2]

Distribution

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 4000 years where the silver trout probably evolved from brook trout. [2] In the deep waters of these lakes, cut off from other species, the silver trout had no natural predators.[ citation needed ]

Extinction

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. [2]

While the silver trout is most likely lost, success stories like the Pyramid Lake (Nevada) Lahontan cutthroat trout and the Sunapee golden trout exist, and there may still be hope for the silver trout.

Related Research Articles

Trout Number of species of freshwater fish

Trout are species of freshwater fish belonging to the genera Oncorhynchus, Salmo and Salvelinus, all of the subfamily Salmoninae of the family Salmonidae. The word trout is also used as part of the name of some non-salmonid fish such as Cynoscion nebulosus, the spotted seatrout or speckled trout.

Salmonidae Family of ray-finned fishes

Salmonidae is a family of ray-finned fish, the only living family currently placed in the order Salmoniformes. It includes salmon, trout, chars, freshwater whitefishes, and graylings, which collectively are known as the salmonids. The Atlantic salmon and trout of the genus Salmo gives the family and order their names.

Lake trout Species of fish

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.

Bull trout Species of fish

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. Bull trout are listed as a threatened species under the U.S. Endangered Species Act (1998) and as vulnerable on the IUCN Red List of Threatened Species.

Rainbow trout Fresh-water species of fish

The rainbow trout is a trout and species of salmonid 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 fresh water 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.

Brook trout Species of fish

The brook trout is a species of freshwater fish in the char genus Salvelinus of the salmon family Salmonidae. It is native to Eastern North America in the United States and Canada, but has been introduced elsewhere in North America, as well as to Iceland, Europe, and Asia. In parts of its range, it is also known as the eastern brook trout, speckled trout, brook charr, squaretail, brookie or mud trout, among others. A potamodromous population in Lake Superior, as well as an anadromous population in Maine, is known as coaster trout or, simply, as coasters. The brook trout is the state fish of nine U.S. states: Michigan, New Hampshire, New Jersey, New York, North Carolina, Pennsylvania, Vermont, Virginia, and West Virginia, and the Provincial Fish of Nova Scotia in Canada.

Golden trout Species of fish

The Brigit, also known as the Californiangolden 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.

Arctic char Species of fish

The Arctic char or Arctic charr is a cold-water fish in the family Salmonidae, native to alpine lakes and arctic and subarctic coastal waters. Its distribution is Circumpolar North. It spawns in freshwater and populations can be lacustrine, riverine, or anadromous, where they return from the ocean to their fresh water birth rivers to spawn. No other freshwater fish is found as far north; it is, for instance, the only fish species in Lake Hazen on Ellesmere Island in the Canadian Arctic. It is one of the rarest fish species in Great Britain and Ireland, found mainly in deep, cold, glacial lakes, and is at risk from acidification. In other parts of its range, such as the Nordic countries, it is much more common, and is fished extensively. In Siberia, it is known as golets and it has been introduced in lakes where it sometimes threatens less hardy endemic species, such as the small-mouth char and the long-finned char in Elgygytgyn Lake.

Sea trout Form of brown trout

Sea trout is the common name usually applied to anadromous forms of brown trout, and is often referred to as Salmo trutta morpha trutta. Other names for anadromous brown trout are sewin (Wales), peel or peal, mort, finnock (Scotland), white trout (Ireland) and salmon trout (culinary). The term sea trout is also used to describe other anadromous salmonids—coho salmon, brook trout, Arctic char, cutthroat trout and Dolly Varden. Even some non-salmonid species are also commonly known as sea trout—Northern pikeminnow and members of the weakfish family (Cynoscion).

Dolly Varden trout Species of fish

The Dolly Varden trout is a species of salmonid fish native to cold-water tributaries of the Pacific Ocean in Asia and North America. It belongs to the genus Salvelinus, or true chars, which includes 51 recognized species, the most prominent being the brook, lake and bull trout, as well as Arctic char. Although many populations are semi-anadromous, fluvial and lacustrine populations occur throughout its range. It is considered by taxonomists as part of the Salvelinus alpinus or Arctic char complex, as many populations of bull trout, Dolly Varden trout and Arctic char overlap.

<i>Salvelinus</i> Genus of fishes

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 Subspecies of fish

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.

Splake Species of fish

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.

Tiger trout Hybrid fish

The tiger trout is a sterile, intergeneric hybrid of the brown trout and the brook trout. The name derives from the pronounced vermiculations, which evoke the stripes of a tiger. The fish is an anomaly in the wild, with the brook trout having 84 chromosomes and the brown trout 80. Records show instances as far back as 1944. The cross itself is unusual in that the parents are members of different genera.

The Mexican golden trout 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.

<i>Salvelinus umbla</i> Species of fish

Salvelinus umbla, also known as lake char, is a species of char found in certain lakes of the region of the Alps in Europe.

Sunapee trout Subspecies of fish

The Sunapee trout; also called blueback trout, Sunapee Golden trout, or Quebec red trout; is a putative subspecies of Arctic char native to the northeast United States, Québec, and New Brunswick. Originally described as three separate species--S. oquassa, the blueback trout of Lake Oquassa in Maine (1854), S. aureolus the golden trout of Sunapee lake in New Hampshire (1888) and S. marstoni the Quebec red trout (1893).

References

  1. World Conservation Monitoring Centre (1996). "Salvelinus agassizii". IUCN Red List of Threatened Species . 1996: e.T19873A9089084. doi: 10.2305/IUCN.UK.1996.RLTS.T19873A9089084.en . Retrieved 19 November 2021.
  2. 1 2 3 Robert J. Behnke (2007). About Trout: The Best of Robert J. Behnke from Trout Magazine. Globe Pequot Press. ISBN   9781599212036 . Retrieved 2014-01-29.