Food habits of the great horned owl in northwestern Argentine Patagonia: the role of introduced lagomorphs
—Pellets of adult and nestling Great Horned Owls (Bitho tirginianus) were collected at 12 owl territories nearJunin de los Andes (Neuquen, Argentine Patagonia) during the breeding seasons of 1991— 92 and 1994—95. Mammals represented 69% of the total prey items (N = 1324) identified and Reithrodon au...
| Autores: | , , , , |
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| Tipo de recurso: | artículo |
| Fecha de publicación: | 1997 |
| País: | España |
| Institución: | Consejo Superior de Investigaciones Científicas (CSIC) |
| Repositorio: | DIGITAL.CSIC. Repositorio Institucional del CSIC |
| OAI Identifier: | oai:digital.csic.es:10261/50769 |
| Acceso en línea: | http://hdl.handle.net/10261/50769 |
| Access Level: | acceso abierto |
| Palabra clave: | Great Horned Owl Bubo virginianus foof habits Patagonia |
| Sumario: | —Pellets of adult and nestling Great Horned Owls (Bitho tirginianus) were collected at 12 owl territories nearJunin de los Andes (Neuquen, Argentine Patagonia) during the breeding seasons of 1991— 92 and 1994—95. Mammals represented 69% of the total prey items (N = 1324) identified and Reithrodon auritus (16%), Lepuseuwpaeus (12%) and Ctenomys haigi (12%) were the most common species. Anhropods aecounted for 27% of the total prey by numbers. The two main prey items by biomasa were the introduced lagomorphs L eurepaeus and Oryctolagus cuniculus (55%) and those prey that we identified were mainly young that weighed <1000g. There were no major variations in the diets of owls between mountain and plains areas, but the diversity of small mammals taken was higher in mountain areas. In plains areas, analysis of variation between the first and second halves of the brood-rearing period showed that rodents increased in the diet near the time of fledging. We felt that the low frequency of lagomorphs in the diet of Patagonian Great Horned Owls in comparison with horned owls at similar latitudes in the northern hemisphere may have been due to the fact that Patagonian horned owls weighed 30—40% less and were constrained in the predatory habits by the large size of adult lagomorphs. Large rodents and young lagomorphs may be more optimal prey for Great Horned Owls in Patagonia. |
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