BLUNT-NOSED LEOPARD LIZARD Crotaphytus silus (Stejneger) 



Order: SQUAMATA Family: IGUANIDAE 



Distinguishing characteristics : A robust lizard with long tail, relatively large head, 

 rather distinct from neck and a blunt snout; dorsal scales granular; above light to 

 dark gray with large dusky spots with whitish crossbars; throat spotted. 



Present distribution : The San Joaquin Valley of central California, the adjacent 

 Carrizo Plains, southward over the Temblor and Caliente Ranges into the Lower Cuyama 

 Valley (mapped in Montanucci, 1970, p. 116). Total area estimated at 600 square miles 

 (Sheppard, 1970) . A locally distributed species absent from many parts of this area 

 (Wilbur , pars . comm . ) . 



Former distribution : Approximately as above . 



Status : Apparently seriously depleted, but see below in "estimated numbers." Listed as 

 endangered by California Department of Fish and Game . 



Estimated numbers : Although earlier indications were that the species was "on the verge 

 of total extermination, " Sheppard, on the basis of a study made of a population in Kern 

 County, California, estimated a population of 100 per square mile. However, population 

 varies with habitat types and much of prime habitat has been destroyed. 



Breeding rate in the wild : Two to seven (average four) eggs laid in June. 



Reasons for decline : Subdivisions, water control, and spread of agriculture is eliminating 

 populations very rapidly and up-to-date information is difficult to obtain. Completion of the 

 California Aqueduct will furnish water to permit agricultural development throughout the 

 San Joaquin Valley . 



Protective measures already taken : Habitat preserved on both Kern and Pixley National 

 Wildlife Refuges; fully protected in California as an endangered species. Inventory initiated 

 by California Department of Fish and Game. 



Measures proposed : Establishment of a national wildlife monument to preserve a sample 

 of the original fauna and flora of the San Joaquin Valley. 



Number in captivity : Few . 



Breeding potential in captivity : Probably slight. 



References : 



Bury, R. B. 1972. Status report on California's threatened amphibians and reptiles. 



Inland Fisheries Report 72-2. Calif. Dept. of Fish & Game. 

 Leach, H. R. and L. D. Fisk . 1972. At the crossroads--a report on California's 



rare and endangered wildlife. Calif. Dept. of Fish & Game. 

 Montanucci, R. R. 1965. Observations on the San Joaquin leopard lizard, 



Crotophytus wislizenii silus Stejneges. Herpetologica 21(4): 270-283 . 

 . 1970. Copeia, 104-123. 



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