Diet Composition of Upland Buzzard:Analysis on Stomach Content and Food Pellet

Contents of 14 stomachs and 118 food pellets were analyzed to trace dietary information of upland buzzards (Buteo hemilasius) living at alpine meadow ecosystem in Maduo County,Qinghai Province.The prey items can be classified into three types:1)plateau pika (Ochotona curzoniae),2) Qinghai vole (Lasiopodomys fuscus),and 3) small birds.The results indicated that the average occurrence frequencies (pi) and biomass ratios (bi) of plateau pika,Qinghai vole and small birds in diets of upland buzzards were 0.28,0.68 and 0.04 as well as 0.59,0.40,and 0.02 respectively.pi and bi of the prey items in food pellets were 0.70,0.27 and 0.02 as well as 0.89,0.10 and 0.01 respectively.Analyses on stomach contents and food pellets generated significant different pi and bi (χ2 test),however,both revealed key roles of plateau pika and Qinghai vole in diets of upland buzzards.