USFWS Bald Eagle Feather Atlas

Welcome! See – Learn – Share. This page features curated images from the Bald Eagle Feather Atlas, a landmark resource developed by the Forensics Laboratory at the U.S. Fish & Wildlife Service (USFWS). The Atlas documents bald eagle feathers across all pre-definitive and definitive molt sequences, from juvenile to adult, offering a visual taxonomy of plumage transformation over time. Each image is authored by the USFWS and has undergone advanced image refinement to enhance clarity, contrast, and structural detail—ensuring that educators, researchers, and students can study feather morphology with precision.

🔍 What’s in a Feather? Every eagle feather includes, 1) a central shaft (rachis) for strength and alignment, 2) barbs and barbules, which interlock to create aerodynamic surface, 3) a calamus (quill) that anchors the feather to the skin, and 4) subtle variations in color, wear, and symmetry that signal age and molt stage. Together, these elements form the architecture of flight, insulation, and identity—each feather a chapter in the eagle’s life story.