Identification of prey species consumed by the great horned owl (Bubo virginianus) in the suburban area of Zacatecas, Mexico

The great horned owl (Bubo virginianus) is a representative bird of the Strigidae family; they are generalist predators, their prey being mainly rodents, lagomorphs, and arthropods, in varying proportions depending on the habitat, time of year, and availability of prey; therefore, taking into account that the analysis of their diet allows for the collection of ecological information on the species; the objective of this study was to identify the species consumed by the great horned owl (Bubo virginianus) in the study area during the rainy and dry seasons in an urbanized area near the city of Zacatecas. To this end, the presence of long-eared owls was located in a rural area of the state of Zacatecas. Once located, pellets were collected during two seasonal periods: the rainy season and the dry season. The samples collected were processed for content analysis (bone remains, molars, skulls, hair, and feathers). To identify prey species, skulls and molars obtained from each sample were identified using specialized reference literature. The data obtained were subjected to principal component analysis (PCA) statistical tests to identify the main prey for each season analyzed, as well as of Mann-Whitney U test analysis to establish the difference between the prey present and the number of individuals consumed in each study season. The results indicated the presence of five genera of the order Rodentia (Peromyscus, Baiomys, Sigmodon, Reithrodontomys, and Chaetodipus), two classes (Aves and Reptilia), and phylum Arthropoda, with the species Peromyscus (31%) and Chaetodipus (29%) being the most frequently identified prey in both seasons. Analysis of the data indicated that there is a significant difference (P>0.05) between the prey identified within the study seasons. It is concluded that the main prey species consumed by horned owls are rodents, which, due to the conditions of the habitat in which they occur, are available throughout the year, and the difference is observed due to the biology of the species.