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.
The brown trout is a European species of salmonid fish that has been widely introduced into suitable environments globally. It includes purely freshwater populations, referred to as the riverine ecotype, Salmo trutta morpha fario, a lacustrine ecotype, S. trutta morpha lacustris, also called the lake trout, and anadromous forms known as the sea trout, S. trutta morpha trutta. The latter migrates to the oceans for much of its life and returns to fresh water only to spawn. Sea trout in Ireland and Britain have many regional names: sewin in Wales, finnock in Scotland, peal in the West Country, mort in North West England, and white trout in Ireland.
Salmo is a genus of ray-finned fish from the family Salmonidae, which includes all European species of salmon and trout, among them the familiar Atlantic salmon and the brown trout. The single Salmo species naturally found in the Atlantic North America is the Atlantic salmon, whereas the salmon and trout of the Pacific basin belong to another genus, Oncorhynchus. The natural distribution of Salmo also extends to North Africa and to West Asia around the Black Sea basin.
The Atlantic salmon is a species of ray-finned fish in the family Salmonidae. It is the third largest of the Salmonidae, behind Siberian taimen and Pacific Chinook salmon, growing up to a meter in length. Atlantic salmon are found in the northern Atlantic Ocean and in rivers that flow into it. Most populations are anadromous, hatching in streams and rivers but moving out to sea as they grow where they mature, after which the adults seasonally move upstream again to spawn.
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).
Salmo trutta fario, sometimes called the river trout, and also known by the name of its parent species, the brown trout, is a predatory fish of the family Salmonidae and a subspecies or morph of the brown trout species, Salmo trutta, which also includes sea trout and a lacustrine trout. Depending on the supply of food, river trout measure 20 to 80 cm (0.7–2.6 ft) in length; exceptionally they may be up to 1 m (3.3 ft) long and weigh up to over 13 kg (29 lb). Their back is olive-dark brown and silvery blue, red spots with light edges occur towards the belly, the belly itself is whitish yellow. River trout usually attain a weight of up to 2 kg (4.4 lb). They can live for up to 18 years.
Ferox trout is a variety of trout found in oligotrophic lakes/lochs of Ireland, England, Scotland and Wales. Ferox trout is a traditional name for large, piscivorous trout, which in Scotland feed largely on Arctic char. It has been argued to be a distinct species, being reproductively isolated from "normal" brown trout of the same lakes, particularly in Ireland. However, it is uncertain whether the ferox of different lakes are all of a single origin. This fish grows to a length of 80 centimetres (31 in) SL.
The Sevan trout is an endemic fish species of Lake Sevan in Armenia, known as ishkhan in Armenian. It is a salmonid fish related to the brown trout.
Gillaroo is a variety of trout which eats primarily snails and is only proven to inhabit Lough Melvin in Ireland.
Ohrid trout or the Lake Ohrid brown trout is an endemic species of trout in Lake Ohrid and in its tributaries and outlet, the Black Drin river, in North Macedonia and Albania. Locally, the fish is known as охридска пастрмка in Macedonian and koran in Albanian.
The tiger trout is a sterile, intergeneric hybrid of the brown trout and the brook trout. Pronounced vermiculations in the fish's patterning gave rise to its name, evoking the stripes of a tiger. Tiger trout are a rare anomaly in the wild, as the parent species are relatively unrelated, being members of different genera and possessing mismatched numbers of chromosomes. However, specialized hatchery rearing techniques are able to produce tiger trout reliably enough to meet the demands of stocking programs.
Dollaghan are a variety of brown trout native to Lough Neagh, Northern Ireland, and many of its tributaries. They are a potamodromous migratory trout spending much of the year in the lough, returning to the rivers in autumn to spawn. Dollaghan are much sought after by anglers in County Antrim, County Tyrone and County Londonderry due to their greater size in comparison to the non-migratory trout found in streams such as the Ballinderry River Six Mile Water, Moyola River and River Main. They are often caught in the dark using methods very similar to that of fishing for sea trout. Many anglers regard them as an elusive species and call them 'sea trout of lough neagh'. Their weight varies greatly - from small fish of around 1/2 lb to large specimens of around 20 lb. There are four strains of brown trout in Ireland: Dollaghan, Gillaroo, Sonaghan and Ferox. The Dollaghan is thought to have evolved from sea trout which were land locked many years ago.
The Sefid-Rud is a river approximately 670 kilometres (416 mi) long, rising in the Alborz mountain range of northwestern Iran and flowing generally northeast to enter the Caspian Sea at Rasht. The river is Iran's second longest river after the Karun.
Salmo dentex is a variety of trout, a freshwater fish in the family Salmonidae, found in the western Balkans. Until recently the identity, biological distinctness and species status of the dentex trout were not properly clarified, but genetic data now suggest it is not a monophyletic unit that could be distinguished from other salmonids as a separate species.
Salmo marmoratus, the marble trout, is a species of freshwater fish in the family Salmonidae. It is characterized by a distinctive marbled color pattern and high growth capacity. The marble trout is found in only a handful of drainages and rivers of the Adriatic basin in Italy, Slovenia, Croatia, Bosnia and Herzegovina, and Montenegro, while in Albania, the species is considered most likely extirpated.
Salmo platycephalus, known as the flathead trout, Ala balik or the Turkish trout, is a type of trout, a fish in the family Salmonidae. It is endemic to southeastern Turkey. It is known only from one population, which occupies three streams, tributaries of the Zamantı River in the Seyhan River basin. The population itself is abundant, but subject to threat by habitat loss, since the range is small. Also, predation of juveniles by introduced rainbow trout may cause population decline. The species is classified as critically endangered.
Salmo ciscaucasicus, the Caspian salmon, is a salmonid fish endemic to the Caspian Sea and its inflowing rivers. It was described in 1967 originally as a subspecies of Salmo trutta. S. ciscaucasicus lives on the western shore of the lake from northern Azerbaijan to the Ural River, while the main breeding river is the Terek. It lives at depths down to 50 m. Males can reach a maximum standard length of 130 cm.
The Abant trout is a salmonid fish native to Lake Abant in northern Anatolia. It was initially described as a subspecies of the brown trout Salmo trutta abanticus Tortonese, 1954, but later even considered a full species Salmo abanticus. On the basis of crossing experiments and mtDNA sequences, Kalayci et al. (2018) however proposed that it should be considered a local strain within Salmo trutta, with no distinct species status.
Salmo farioides, commonly known as the West Balkan trout, the Adriatic brown trout, or the Balkan brook trout, is a species of ray-finned fish found in the Balkans, including Albania, Croatia, North Macedonia, among others. It is an important fish in numerous rivers and lakes throughout the region. Identification of Salmo farioides is difficult due to the high degree of endemism in the western Adriatic and Mediterranean area, particularly among salmonid species, and because of high phenotypic diversity among trout populations specifically.
