Of the 55 species and about 10 hybrids of native or introduced freshwater fish known in the British Isles, 35 have been recorded in Cornwall. Some of these are anadromous or catadromous, spending part of their life cycle in the open sea. Cornish rivers are for the most part narrow and of limited extent and it is not surprising that freshwater fish are scarce, although there are generally more species in the substantial river systems in east Cornwall. Gainey, in Spalding, A. (Ed.) 1997, has reviewed the status of the freshwater fish in Cornish rivers and estuaries. There are no rare fish species present, but several which can be considered as Locally Scarce (LS), provisionally Nationally Scarce (pNS) or a Species of Conservation Concern (SoCC). (The anadromous Sea Lamprey, Sturgeon, Twaite and Allis Shad, Atlantic Salmon and Brown Trout are included in the marine section).
The information for this account was taken from Clark (1906), Davies et al. (2004), Maitland (1972), Newdick (1979), Reay (1988a) and Sambrook (1987). Information given from the Environment Agency’s electric-fishing surveys in Cornwall and further comments by Mr R. Hurrell have proved most helpful.
Anguilla anguilla European Eel
Cottus gobio Bullhead/ Millerís Thumb
Gymnocephalus cernua Ruffe/ Pope
Lampetra fluviatilis River Lamprey/ Lampern
Lampetra planeri Brook Lamprey
Leuciscus leuciscus Dace
Neomacheilus barbatulus Stone Loach
Osmerus eperlanus European or Cucumber Smelt ( Sparling)
Thymallus thymallus Grayling