RIO GRANDE CUTTHROAT TROUT Salmo clarki virginalis (Girard, 1856) 



Order: SALMONIFORMES Family: SALMONIDAE 



Significance : Original native cutthroat trout in the Rio Grande drainage in Colorado. 



Distinguishing characteristics : A large trout, reaches 24 to 30 inches in length, 

 vertebrae 60-63; scales 145-175 in lateral series, 35-40 above lateral line. 



Present distribution : Headwater streams on Trinchera Ranch, tributaries to Rio Grands, 

 Costilla County, Colorado; also, a few streams in Sandoval and Taos Counties in northern 

 New Mexico . 



Former distribution : Headwaters of the upper Rio Grande drainage . 



Status : Scarce . 



Estimated numbers : No data. 



Fecundity : Probably similar to other cutthroats . 



Reasons for decline : Pollution, water diversion for irrigation, hybridization with 

 introduced species, competition with introduced trouts . 



Protective measures already taken : Brood stock were collected by the Colorado Game, 

 Fish and Parks Department for propagation purposes; one stream in New Mexico is 

 closed to fishing and a barrier was installed. 



Measures proposed : Introduction in a new lake; culture for stocking suitable waters 

 in the Rio Grande basin. 



Number in captivity : No data . 



Breeding potential in captivity : No data . 



Remarks : Data submitted by Drs . R. E. Vincent and R.J. Behnke, Colorado Cooperative 

 Fishery Unit, Bureau of Sport Fisheries and Wildlife and Region 3, U.S. Forest Service. 



References : 



Green, W. S. , Jr. 1937. Colorado trout. Colorado Museum of Natural History 



Popular Series No. 2, 48 p . 

 Jordan, D. S. and B. W. Evermann. 1902. American food and game fish. 



Doubleday, Page & Co., N.Y. 572 p. 



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