Parasitic Jaeger

Seen while walking down from the park ring road where we parked on the shoulder. A dark silhouette, similar in size and shape to Ring-billed Gulls which were also present. Slightly smaller-headed and shorter-legged than Ring-billed Gull, and more barrel-chested. Bird was stationary. Upon getting closer, the plumage was well-lit and we could see it was a uniform deep dark brown, almost black. Brown was cool toned with hints of gray. Photos taken reveal some very faint lighter brown edging on the feathers. Eye was dark, basically blending in with the plumage. Legs pale grey. Bill small thin and straight, gray with a dark tip, where the culmen curved down. Wings long and pointed, protruding past the tail.
(see photos)