The huchen (''Hucho hucho'') (, from

German German(s) may refer to: * Germany (of or related to) ** Germania (historical use) * Germans, citizens of Germany, people of German ancestry, or native speakers of the German language ** For citizens of Germany, see also German nationality law **Ge ...

), also known as Danube salmon or redfish (german: Rotfisch), is a large species of

freshwater fish Freshwater fish are those that spend some or all of their lives in fresh water, such as rivers and lakes, with a salinity of less than 1.05%. These environments differ from marine conditions in many ways, especially the difference in levels of ...

in the

salmon Salmon () is the common name for several commercially important species of euryhaline ray-finned fish from the family Salmonidae, which are native to tributaries of the North Atlantic (genus ''Salmo'') and North Pacific (genus '' Oncorhy ...

family of order

Salmoniformes Salmonidae is a family of ray-finned fish that constitutes the only currently extant family in the order Salmoniformes . It includes salmon (both Atlantic and Pacific species), trout (both ocean-going and landlocked), chars, freshwater whitefis ...

. It is the

type species In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specime ...

of its

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...

Hucho ''Hucho'' is a genus of large piscivorous salmonid fish known as taimens (from Finnish through Russian ), and is closely related to Pacific trout and lenoks (all belonging to the same tribe in the subfamily Salmoninae). Native to the cold ...

''.

Distribution and ecology

The huchen is

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found else ...

to the

Danube The Danube ( ; ) is a river that was once a long-standing frontier of the Roman Empire and today connects 10 European countries, running through their territories or being a border. Originating in Germany, the Danube flows southeast for , p ...

basin in Europe where the remaining population is threatened primarily by river

damming A dam is a barrier that stops or restricts the flow of surface water or underground streams. Reservoirs created by dams not only suppress floods but also provide water for activities such as irrigation, human consumption, industrial use, a ...

, resulting in habitat fragmentation and loss through river impoundment and disruption of the longitudinal continuity of rivers, cutting away fish from its

spawning grounds A spawning bed is an underwater solid surface on which fish spawn to reproduce themselves. In fishery management, a spawning bed is an artificial bed constructed by wildlife professionals in order to improve the ability of desired game fish to r ...

, with overfishing and fisheries mismanagement as an additional issue in many areas. Damming and all these other problems are especially visible in the

Balkans The Balkans ( ), also known as the Balkan Peninsula, is a geographical area in southeastern Europe with various geographical and historical definitions. The region takes its name from the Balkan Mountains that stretch throughout the who ...

. The upper reaches of the Danube basin, rivers and tributaries contain almost all of the recent population. This includes: *In

Austria Austria, , bar, Östareich officially the Republic of Austria, is a country in the southern part of Central Europe, lying in the Eastern Alps. It is a federation of nine states, one of which is the capital, Vienna, the most populous ...

: the Inn river, the upper Drava in

Lower Austria Lower Austria (german: Niederösterreich; Austro-Bavarian: ''Niedaöstareich'', ''Niedaestareich'') is one of the nine states of Austria, located in the northeastern corner of the country. Since 1986, the capital of Lower Austria has been Sankt P ...

, with the lower

Gail Gail may refer to: People *Gail (given name), list of notable people with the given name Surname * Jean-Baptiste Gail (1755–1829), French Hellenist scholar * Max Gail (born 1943), American actor * Sophie Gail (1775–1819), French singer and ...

in Carinthia, the Pielach, in Styria the upper Mur. *In

Germany Germany,, officially the Federal Republic of Germany, is a country in Central Europe. It is the second most populous country in Europe after Russia, and the most populous member state of the European Union. Germany is situated betwe ...

: middle and lower Inn, Isar (especially in Munich) In the

huchen still appears in following river systems: *In

Slovenia Slovenia ( ; sl, Slovenija ), officially the Republic of Slovenia (Slovene: , abbr.: ''RS''), is a country in Central Europe. It is bordered by Italy to the west, Austria to the north, Hungary to the northeast, Croatia to the southeast, an ...

: in the headwaters of

Sava The Sava (; , ; sr-cyr, Сава, hu, Száva) is a river in Central and Southeast Europe, a right-bank and the longest tributary of the Danube. It flows through Slovenia, Croatia and along its border with Bosnia and Herzegovina, and finally t ...

and its tributaries. *In

Croatia , image_flag = Flag of Croatia.svg , image_coat = Coat of arms of Croatia.svg , anthem = "Lijepa naša domovino"("Our Beautiful Homeland") , image_map = , map_caption = , capit ...

: in the upper and middle course of

Kupa The Kupa () or Kolpa ( or ; from la, Colapis in Roman times; hu, Kulpa) river, a right tributary of the Sava, forms a natural border between north-west Croatia and southeast Slovenia. It is long, with its border part having a length of and t ...

. *In

Bosnia and Herzegovina Bosnia and Herzegovina ( sh, / , ), abbreviated BiH () or B&H, sometimes called Bosnia–Herzegovina and often known informally as Bosnia, is a country at the crossroads of south and southeast Europe, located in the Balkans. Bosnia and H ...

: in the upper and middle

Una Una and UNA may refer to: Places * 160 Una, the asteroid "Una", an asteroid named after the Faerie Queene character * Una River (disambiguation), numerous rivers * Una, Himachal Pradesh, a town in India ** Una, Himachal Pradesh Assembly constit ...

, with the upper and middle

Sana Sana may refer to: Places * Sanaa, the capital of Yemen * Sana (river), a river in Bosnia and Herzegovina * Sana, Bhutan, a town in Bhutan * Sana, Haute-Garonne, a commune in France * Sana, Iran, a village in Iran * Sana, Mali, a commune in M ...

; the upper and middle Vrbas, with the lower and middle Vrbanja; the main channel of the Bosna lost its population due to degradation of its waters, its banks and riverbed, but its four main tributaries, the Krivaja, the Fojnička, the

Lašva The Lašva ( sr-cyrl, Лашва) is a river in Central Bosnia, Bosnia and Herzegovina. It is a left tributary of the Bosna.Vojnogeografski institut, Ed. (1955): Travnik (List karte 1:100.000, Izohipse na 20 m). Vojnogeografski institut, Beograd / ...

and the Željeznica, are still important habitats; one of the most important huchen habitats in Balkan and Europe is the

Drina The Drina ( sr-Cyrl, Дрина, ) is a long Balkans river, which forms a large portion of the border between Bosnia and Herzegovina and Serbia. It is the longest tributary of the Sava River and the longest karst river in the Dinaric Alps whi ...

, with its numerous tributaries, especially the Lim, the Tara and the

Ćehotina The Ćehotina (Serbian Cyrillic: Ћеxотина, ), also known as the Ćeotina, Ćotina or Čehotina, is a long river in Montenegro and Bosnia and Herzegovina. It is a right bank tributary of the Drina river.Bistrica, the Prača, and the

Drinjača Drinjača (Serbian Cyrillic: Дрињача) is a left tributary of the Drina in eastern Bosnia and Herzegovina. It rises on the mountain of Konjuh (1,326 m) 15 km northeast of Kladanj at an elevation of about 1,000 m and ends after 87.5 ...

; * In

Serbia Serbia (, ; Serbian: , , ), officially the Republic of Serbia (Serbian: , , ), is a landlocked country in Southeastern and Central Europe, situated at the crossroads of the Pannonian Basin and the Balkans. It shares land borders with Hungar ...

: the Lim. * In

Montenegro ) , image_map = Europe-Montenegro.svg , map_caption = , image_map2 = , capital = Podgorica , coordinates = , largest_city = capital , official_languages = M ...

: the Lim, with the Lake Plav, the Ćehotina, and the Tara. Some of these habitats, especially in the Balkans, are endangered with planned, or already implemented plans for construction of new dams and

hydroelectric power plant Hydroelectricity, or hydroelectric power, is electricity generated from hydropower (water power). Hydropower supplies one sixth of the world's electricity, almost 4500 TWh in 2020, which is more than all other renewable sources combined an ...

s, such as on the Lim in Serbia, or like in case of the river

Piva Piva may refer to: * Piva (river), a river in Montenegro and Bosnia and Herzegovina * Piva, Montenegro, a region in Montenegro and tribe * Piva River, Bougainville, Papua New Guinea * Piva Trail, Bougainville, Papua New Guinea ** Battle for Piv ...

in Montenegro and Bosnia and Herzegovina, whose respective populations were completely wiped out since mid 20th century. In some cases rehabilitation of parts of the habitat is attempted, through restoration of the river course. Such positive example is the part of the course of the river Inn, with some -long stretch around the Bavarian town of

Mühldorf Mühldorf am Inn (Central Bavarian: ''Muihdorf am Inn'') is a town in Bavaria, Germany, and the capital of the district Mühldorf on the river Inn. It is located at , and had a population of about 17,808 in 2005. History During the Middle Ages, ...

was rebuilt and renaturalized and the huchen has returned in recent years. It has been introduced to other major river basins elsewhere on the continent and even North Africa, to rivers in

Morocco Morocco (),, ) officially the Kingdom of Morocco, is the westernmost country in the Maghreb region of North Africa. It overlooks the Mediterranean Sea to the north and the Atlantic Ocean to the west, and has land borders with Algeria t ...

, but these populations are not self-sustaining. Some evidence suggest that in historic times the huchen has also been found in the neighboring

Dniester The Dniester, ; rus, Дне́стр, links=1, Dnéstr, ˈdⁿʲestr; ro, Nistru; grc, Τύρᾱς, Tyrās, ; la, Tyrās, la, Danaster, label=none, ) ( ,) is a transboundary river in Eastern Europe. It runs first through Ukraine and th ...

basin. Huchen sometimes successfully establish in accessible natural lakes, like glacial Lake Plav which is the source of the Lim river in Montenegro, one of the major huchen habitats in the Balkans. However, the species sometimes survives even when cut off from the rest of the population in big dam reservoirs on mountain rivers, such as reservoirs on the Drina in Bosnia, or Lake Czorsztyn in Poland, as long as competitive and/or allochthonous predator species are not introduced into the newly created lakes.

Appearance and behaviour

The huchen reaches about in length and more than in weight. The average length is between . The huchen has a slender body that is nearly round in cross-section. On the reddish brown back are several dark patches in an X or crescent shape, but most distinctive feature is fishes head, which is larger than in other salmonides (longer and wider), with large elongated mouth. Smaller fish feed on the larvae of water insects or on insects dropped into the water; the larger individuals are predators of other species of fish and other small vertebrates.

Historical occurrence

There is no international convention nor single agreed body concerned with verification of records and mandated with the task, however there are many modern and historical records for the largest huchen caught. Among these recorded is fish weighing , caught in February 1985 in

Spittal an der Drau Spittal an der Drau is a town in the western part of the Austrian federal state of Carinthia. It is the administrative centre of Spittal an der Drau District, Austria's second largest district ('' Bezirk'') by area. Geography The town is located ...

,; also one weighing , which is stuffed and was probably grown on fish-farm in Austria for breeding. Other storied examples of recorded specimens with existing photographs and media reports include , caught in January 1938 by Bosnian railway worker and angler Halil Sofradžija at the Dragojevića Rapids on the Drina river, near the town of Ustikolina in Bosnia and Herzegovina. This case was recorded on photograph and reportage was later published in prime Serbian daily

Politika ''Politika'' ( sr-Cyrl, Политика; ''Politics'') is a Serbian daily newspaper, published in Belgrade. Founded in 1904 by Vladislav F. Ribnikar, it is the oldest daily newspaper still in circulation in the Balkans. Publishing and owners ...

on 23 February 1938. Dževat Šarkinović, angler from Plav, caught Danube salmon weighting , long, in late spring of 1985 in lake Plav, and gave it to Hotel "Plavsko jezero" who presented it at '' International Fair of Hunting and Fishing'' in Novi Sad where it was noted as a "world record". Today, this specimen stands as stuffed exhibit at the wall of hotel's foyer in Plav. Another recorded trophy from the Drina include huchen caught by angler Remzija Krkalić from

Foča Foča ( sr-Cyrl, Фоча, ) is a town and a municipality located in Republika Srpska in south-eastern Bosnia and Herzegovina, on the banks of Drina river. As of 2013, the town has a population of 12,234 inhabitants, while the municipality has 1 ...

in 1940, weighing .

Reproduction

This permanent freshwater salmonid spawns in April, once water reaches a temperature of . For spawning, the huchen migrates up the river and enters small and shallow affluents, where females excavate depressions in the gravel into which they deposit their eggs, then a male releases a cloud of sperm and the female then covers the eggs with sand. Larvae hatch 30 to 35 days after fertilization.

Commercial breeding

FMIB 49426 Huchen 46 lbs taken in the Inn River, Bavaria, by Ludwig Deiglmayer

There is a considerable effort to produce huchen fry commercially and to reintroduce the species into the wild with moderate to good success. This requires catching the adults just before spawning and keeping them in special tanks. Fry are released in appropriate places once they have reached .

References

{{Authority control Hucho Freshwater fish of Europe Fish described in 1758 Taxa named by Carl Linnaeus