Food habits of Mexican SpottedOwls in Arizona

-Mammals accounted for 73-96% of total prey and 91-99% of prey biomass. Owls consumed prey ranging in mass from beetles (Coleoptera) and moths (Lep- idoptera) (ca 1 g) to adult cottontail rabbits (SyZvilugus spp.; ca 650 g 
-Woodrats, white-footed mice (Peromyscus spp.), and voles (Microtus spp.) accounted for 61-83% of the total prey
 -In general, woodrats and white-footed mice were common in the diet (Z 10% of total prey) in all regions.
 -Dietary composition during the breeding season varied significantly among years (Table 2; x2 = 45.7, df = 12, P < 0.001; N = 4 years and 655 items).
 -I could not compare dietary composition among seasons because most data (79%) were collected during the breeding season. In general, fewer bats and insects were taken during the nonbreeding season (1 September-28 February; Ganey and Balda 1989b) than during the breeding season, whereas the most common mammalian taxa were taken in relatively high numbers in both seasons.
 - side note: wood rats were more abundant in the canyon (These species are most abundant around rock outcrops and cliffs); Voles were more abundant in the forest (species that are more abundant in the grassy understories of forests in the latter regions)
http://www.fs.fed.us/rm/pubs_other/rmrs_1992_ganey_j001.pdf