Diet and Feeding Strategies of the Crested Eagle (Morphnus guianensis) in the Brazilian Amazon

Abstract

The Crested Eagle (Morphnus guianensis) is the second largest Brazilian forest eagle. Crested Eagles are distributed from southeastern Mexico to southern Brazil, northern Argentina, and Paraguay; however, the species is one of the least-studied Neotropical raptors. Our objective was to determine diet and feeding strategies for Crested Eagles in the Brazilian Amazon. We recorded Crested Eagle diet at four nests from 2010-2012 through a combination of direct observations from the ground, remote photographs (camera-traps), and pellets and prey remains collected in and under the nests. We identified a total of 79 prey individuals, composed of 21 different prey species. We found that Crested Eagles fed mainly on medium-sized rodents, and medium-sized to large mammals. Prey were mainly nocturnal (70%), including mostly scansorial, cavity-dwelling marsupials and rodents. Fewer prey were diurnal (20%) and these were typified by arboreal, gregarious mammals (monkeys); rare prey included one owl (Strigidae) and one porcupine (Coendou sp.). We suggest that this may indicate a diet not specialized on a particular prey species or group, but rather focused on specific prey behaviors or microhabitats. © 2021 The Raptor Research Foundation, Inc.