Schelly
Encyclopedia
The schelly is a designation for four populations of freshwater whitefish
in the English
Lake District
, Cumbria
. The native populations of this fish inhabit the Brothers Water
, Haweswater
, Red Tarn
and Ullswater
, and occupy a total area of about 20 square kilometers. Apart from Haweswater, the populations appear stable.
At Haweswater, the fishery officers are now culling all of the cormorant
s that visit the lake, in order to protect the endangered fish. An analysis of reservoir management data over a 30 year period (1961-1991) has revealed that the decline of the schelly population is associated with increased water abstraction and reduced water levels. Entrapment during abstraction is not significant. Year class strength is probably determined by lake levels during the January-March spawning and incubation period whereas subsequent growth rate is influenced by lake levels during June-October.
In Britain the schelly populations are usually considered as members of the widespread Eurasian whitefish species Coregonus lavaretus, or common whitefish, as with the Welsh gwyniad
and Scottish powan
. The schelly is however listed as a distinct species of Coregonus
, C. stigmaticus, in FishBase
and by the IUCN.
Freshwater whitefish
The freshwater whitefish are fish of the subfamily Coregoninae in the salmon family Salmonidae. Along with the freshwater whitefish, the Salmonidae includes the freshwater and anadromous trout and salmon species as well as graylings...
in the English
England
England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...
Lake District
Lake District
The Lake District, also commonly known as The Lakes or Lakeland, is a mountainous region in North West England. A popular holiday destination, it is famous not only for its lakes and its mountains but also for its associations with the early 19th century poetry and writings of William Wordsworth...
, Cumbria
Cumbria
Cumbria , is a non-metropolitan county in North West England. The county and Cumbria County Council, its local authority, came into existence in 1974 after the passage of the Local Government Act 1972. Cumbria's largest settlement and county town is Carlisle. It consists of six districts, and in...
. The native populations of this fish inhabit the Brothers Water
Brothers Water
Brothers Water is in the Hartsop valley and is a small lake in the eastern region of the English Lake District, in the county of Cumbria. Once called Broad Water, it lies at the northern end of Kirkstone Pass, affording picturesque views on the descent towards Patterdale.Dorothy Wordsworth, having...
, Haweswater
Haweswater Reservoir
Haweswater is a reservoir in the English Lake District, built in the valley of Mardale in the county of Cumbria. The controversial construction of the Haweswater dam started in 1929, after Parliament passed an Act giving the Manchester Corporation permission to build the reservoir to supply water...
, Red Tarn
Red Tarn
Red Tarn is a small lake in the eastern region of the English Lake District, in the county of Cumbria. It is high up on the eastern flank of Helvellyn, beneath Striding Edge and Catstye Cam....
and Ullswater
Ullswater
Ullswater is the second largest lake in the English Lake District, being approximately nine miles long and 0.75 miles wide with a maximum depth of slightly more than ....
, and occupy a total area of about 20 square kilometers. Apart from Haweswater, the populations appear stable.
At Haweswater, the fishery officers are now culling all of the cormorant
Cormorant
The bird family Phalacrocoracidae is represented by some 40 species of cormorants and shags. Several different classifications of the family have been proposed recently, and the number of genera is disputed.- Names :...
s that visit the lake, in order to protect the endangered fish. An analysis of reservoir management data over a 30 year period (1961-1991) has revealed that the decline of the schelly population is associated with increased water abstraction and reduced water levels. Entrapment during abstraction is not significant. Year class strength is probably determined by lake levels during the January-March spawning and incubation period whereas subsequent growth rate is influenced by lake levels during June-October.
In Britain the schelly populations are usually considered as members of the widespread Eurasian whitefish species Coregonus lavaretus, or common whitefish, as with the Welsh gwyniad
Gwyniad
The gwyniad is a freshwater whitefish native to Bala Lake in northern Wales.The population is threatened by deteriorating water quality and by the ruffe, a fish introduced to the lake in the 1980s and now eating the eggs and fry of gwyniad...
and Scottish powan
Powan
The powan is a kind of freshwater whitefish endemic to two lochs in Scotland, Loch Lomond and Loch Eck. It has been successfully introduced in two other sites, Loch Sloy and the Carron Valley Reservoir....
. The schelly is however listed as a distinct species of Coregonus
Coregonus
Coregonus is a diverse genus of fish in the salmon family . The type species is the common whitefish . The Coregonus species are known as whitefishes...
, C. stigmaticus, in FishBase
FishBase
FishBase is a comprehensive database of information about fish species . It is the largest and most extensively accessed online database on adult finfish on the web...
and by the IUCN.