Dunn, E. H., & Tessaglia, D. L. (1994). Predation of Birds at Feeders in Winter (Depredación de Aves en Comederos Durante el Invierno). Journal of Field Ornithology, 65 (1) 8-16.
A continentwide survey of homes with bird feeders produced 567 reports documenting 1138 incidents of predation. Of the 25 species of predators recorded, three (Sharp-shinned Hawk, Accipiter striatus; domestic cat; Cooper's Hawk, A cooperii) were responsible for 80% of the incidents in which the predator was known. Ten of the 62 species of prey identified accounted for 92% of all victims. The birds most vulnerable to predation were those that commonly occur at feeders throughout the continent (i.e., the most widespread species), but additionally, flocking species were more vulnerable to avian predators than more solitary ones. Prey size was correlated to size of avian predators, but cats concentrated on small birds. Hawks were attracted to feeders with particularly high levels of bird activity, but cats were not. The bird-feeding environment does not appear to expose birds to a higher risk of predation than is encountered in the absence of feeders.
A continentwide survey of homes with bird feeders produced 567 reports documenting 1138 incidents of predation. Of the 25 species of predators recorded, three (Sharp-shinned Hawk, Accipiter striatus; domestic cat; Cooper's Hawk, A cooperii) were responsible for 80% of the incidents in which the predator was known. Ten of the 62 species of prey identified accounted for 92% of all victims. The birds most vulnerable to predation were those that commonly occur at feeders throughout the continent (i.e., the most widespread species), but additionally, flocking species were more vulnerable to avian predators than more solitary ones. Prey size was correlated to size of avian predators, but cats concentrated on small birds. Hawks were attracted to feeders with particularly high levels of bird activity, but cats were not. The bird-feeding environment does not appear to expose birds to a higher risk of predation than is encountered in the absence of feeders.
Se hizo una encuesta, a nivel continental, en residencias en donde se les provee de comederos a aves, que produjo 567 informes en los cuales se documentan 1138 incidentes de depredación. De las 25 especies de depredadores informados tres de éstos, a saber Accipiter striatus, A. cooperii y el gato doméstico, fueron responsables del 80% de los incidentes en donde el depredador fue identificado. Diez de las 62 especies que sirvieron como presas, formaron el 92% de todas las víctimas. Las aves más vulnerables a la depredación fueron aquellas que más comúnmente utilizan comederos artificiales a nivel continental (ej. las especies más ampliamente distribuidas). No obstante las aves que se alimentan en grupos resultaron más vulnerables que las que lo hacen de forma solitaria. El tamaño de la presa se correlacionó al tamaño del depredador, aunque los gatos concentraron sus esfuerzos en aves pequeñas. Los halcones fueron atraídos a comederos, con altos niveles de actividad aviar, mientras que ocurrió lo opuesto con los gatos. Los ambientes en donde hay comederos artificiales no parecen exponer a las aves a un riesgo mayor de depredación, que en lugares en donde éstos no se encuentran.
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