OWENS PUPFISH Cyprinodon radiosus (Miller, 1948) 



Order: ATHERINIFORMES Family: CYPRINODONTIDAE 



Distinguishing characteristics : A pupfish with dorsal fin far forward, first dorsal ray 

 thickened, a terminal black band on caudal fin of male, and 7 pelvic rays. 



Present distribution : Confined to several small areas in Fish Slough, Owens Valley, 

 California, and to a small pond north of Big Pine, Owens Valley, California. 



Former distribution: Owens Valley from the vicinity of Lone Pine, Inyo County, north 

 to Fish Slough, Mono County, California. 



Status : Thought to have been extinct since 1939, but rediscovered at one locality in 

 July 1964. 



Fecundity : Unknown . 



Reasons for decline : Introduction of exotics; habitat alteration . 



Protective measures already taken : A population was reestablished in the California 

 Owens Valley Native Fish Sanctuary in 1970. Rehabilitation of the marsh by building 

 water control structures and removing exotic fish. Classed as endangered by State of 

 California and fully protected under State law . 



Measures proposed : Continued surveillance . Establish additional populations in refuges 

 on BLM land in Fish Slough and at Warm Springs south of Bishop, California. 



Number in captivity : A few at the University of California, Los Angeles. 



Culture potential in captivity : Fair . 



Remarks : This species, thought to have been extinct for the past 20 years or so, still 

 survives but urgently needs protection if it is to persist. It is one of the most distinctive 

 (in breeding coloration, especially) of the species of Cyprinodon . Data submitted by 

 Dr. Robert R. Miller, University of Michigan and Edwin P. Pister, California Department 

 of Fish and Game , Bishop . 



References : 



Miller, R. R. 1948. The cyprinodont fishes of the Death Valley system of eastern 



California and southwestern Nevada. Misc. Publ . Mus. Zool . Univ. Mich., 



No. 68:1-155, figs. 1-5, pis. 1-15, maps 1-3. 

 . 1961 Man and the changing fish fauna of the American Southwest. 



Pap. Mich. Acad. Sci . , Arts, and Letters, 46 (1960): 365-404, fig. 1. 

 and E. P. Pister. 1971. Management of the Owens pupfish, Cyprinodon 



radiosus , in Mono County, California. Trans. Amer. Fish-Soc. 100(3): 502-509. 

 Pister, E. P. 1970. The rare and endangered fishes of the Death Valley system — 

 a summary of the proceedings of a symposium relating to their protection and 

 preservation. California Department of Fish and Game (Mimeo), 23 p. 



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