Very rare, mostly on Dry Tortugas. Polymorphic and variable. 2 morphs in E: white-tailed brown morph and brown-tailed brown morph. ID: Small, slim, with buoyant flight. Imms: brown, palest on belly, often with a hooded look. Imms’ feet are pink, adults’ red. All records either juv or 2nd-yr birds. Juvs: not identifiable to morph. Central tail feathers whitish in 2nd-yr white-tailed morph.