Presence of the reservoir may have affected territorial be- 

 havior and interrupted movements of some of the resident mountain 

 lions. Mountain lions occupy fairly large home ranges with exten- 

 sive movements within the ranges (Seidensticker et al. 1973). Loss 

 of all or portions of one or more mountain lion territories may have 

 had an additional negative impact on the population. Displacement 

 of lions into adjacent territories creates stress which may adverse- 

 ly affect the productivity of the population (M. Hornocker 1983, 

 pers. commun.). Brown (1983, pers. commun.) has observed mountain 

 lion tracks crossing the reservoir during the winter. He suspected 

 this movement was by males searching for mates during the breeding 

 season . 



5) Estimated Losses Due to the Project 



- Quantitative loss estimate - based on the reduction of the 

 preferred prey base. 



- White-tailed deer 



- 12,027 acres of winter range inundated; 1,467-2,221 

 white-tailed deer lost due to reduced availability of 

 winter range. 



- Mule deer 



- 12,180 acres of winter range inundated; 716 mule deer 

 lost due to reduced availability of winter range. 



- 200-300 mule deer lost due to collisicn with vehicles 

 during the 10 years since completion of Highway 37. 



- 4,987 acres of spring range were lost. 



- Bighorn Sheep 



- 4,350 acres of winter/spring range lost; 78 to 102 

 bighorn sheep lost due to reduction in suitable habitat 

 and increased disturbance. 



- Qualitative loss estimate of moderate was assessed. 



6) Derivation of Loss Estimates 



The quantitative loss estimate was expressed as a loss of the 

 known prey base - big game populations. Loss of white-tailed deer 

 (1,467-2,221) was based on tlie reduction in available winter range 

 (12,027 acres). The mule deer loss (716) was based on the re- 

 duction in available winter rcinge (12,180 acres) and spring range 

 (4,987 acres). Loss of bighorn sheep (78-102 animals) was based on 

 the inundation of 4,350 acres of winter/spring range. The qualita- 

 tive loss estimate was based on the quantitative losses and on 



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