field marks are tag alongs

Any birder who uses field marks to identify raptors is working under a handicap. What if the lighting conditions are of a low quality? What if the bird is turned the "wrong way"? What if leaves or limbs blog your view? How will you treat unusual plumage? What if the bird gives you a three-second look - then flies off its perch? And that raptor in the sky, giving you that 10-minute look, remains intellectually unresolved. To see a perched Goshawk is a "rare event". But this rare event is but one side of a coin. Northern Goshawks can be an elusive species, but not in the sky!