Conservationists say one of the world's largest eagles has "nearly zero" chance of surviving Amazon deforestation.
According to a new study, the bird is struggling to feed its young in parts of the rainforest that have been stripped of trees.
About 17% of the Amazon has been destroyed over the past 50 years, and losses have recently been on the rise.
The harpy eagle is the largest in the Americas, with huge talons for hunting monkeys and sloths in the treetops.
The Amazon is regarded as the "last stronghold" for the harpy, with more than 90% of the existing population thought to reside there.
The bird is among millions of animals in the Amazon whose geographic range is shrinking, said study researcher Carlos Peres, professor of environmental sciences at the University of East Anglia, UK.
Conservation measures, such as moving young eagles and supplementing their diets, will be critical to the survival of the species, Prof Peres added.