19 



Table 2. Prey items identified in pellets and prey remains 

 at Ferruginous Hawk nests. 



Taxon 



Number 



Insects 



Red-legged Grasshopper 

 Acrididae 



12 



13.79 



Meunmals 



Lagomorpha 



Cottontail Rabbit 



Sylvalagus sp. 4 



White-tailed Jackrabbit 



Lepus townsendii 1 



unident. lagomorph 1 



total lagomorphs (6) 



Rodentia 



Northern Pocket Gopher 



Thomomys talpoides 6 



Ground Squirrel 



Spermophilus sp.* 3 7 



Vole 



Microtus sp.** 4 



Sagebrush Vole 



Laqurus curtatus 1 



Deermouse 



Peromyscus maniculatus 1 

 unident. rodent 3 



total rodents (49) 



total mammals (55) 



Birds 



Sage Thrasher 7 



Oreoscoptes montanus 

 Horned Lark 4 



Eremophila alpestris 

 Black-billed Magpie 1 



Pica pica 

 Vesper Sparrow 1 



Poot cetes qramineus 

 unident. bird 4 



total birds (17) 



Total 



Diversity indices: 

 H' = 2.01 

 Nl = 7.50 

 N2 = 4.71 



4.60 



1.15 

 1. 15 



(6.90) 



87 



* S. armatus or S. eleqans 



** M. lonqicaudus or M. montanus 



