Article

Bald Eagle Predation of a White-Tailed Deer Fawn

Authors:
  • Illinois Department of Natural Resorces
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Abstract

Haliaeetus leucocephalus (Bald Eagle) is an adaptable predatory bird that commonly captures live prey, but regularly scavenges. Large mammalian prey (e. g., Odocoileus virginianus [White-tailed Deer]) have been observed in Bald Eagle diets, but were considered scavenged. To our knowledge, Bald Eagle prédation of a live ungulate has only been reported once, and occurred in Menominee County, MI. In June 2009, we captured and radiocollared a female White-tailed Deer fawn (2.7 kg) in the south-central Upper Peninsula of Michigan. The fawn was last radiolocated alive 8 h after release in a short-height (20-30 cm) grassland field along a river approximately 570 m from an eagle nest. Estimated time of mortality of the fawn was 10 h post release. Approximately 27 h post release, 2 legs, > 50% fawn hide, and the radiocollar were present in the nest along with 2 eagle nestlings (estimated age 9-10 wks). We believe this was a possible prédation event based on the 8-h period between fawn relocations, fawn movement, foraging behavior of the nesting eagles, and presence of the carcass remains and radiocollar in the nest.

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... Coyotes were the leading cause of fawn mortality across years, followed by bobcats (Table 4.2). One fawn (3 days old) was killed by a bald eagle (Haliaeetus leucocephalus; Duquette et al. 2011). In 9 cases I was unable to determine the species causing predation. ...
... Potential predators of desert mule deer in our study area included mountain lion (Puma concolor), American black bear (Ursus americanus), coyote (Canis latrans), bobcat (Lynx rufus), and gray fox (Urocyon cinereoargenteus). Golden eagle (Aquila chrysaetos) and bald eagle (Haliaeetus leucocephalus) were also present and have the ability to prey upon fawns (Goodwin, 1977;Duquette et al., 2011). The public used the area primarily for outdoor recreation. ...
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