Northern Harriers are considered one of the most elusive raptors, and some of the most accomplished wildlife photographers admit how difficult they are to photograph. Male Harriers, with their white underside and opaque gray-back plumage, seem to be even more challenging to photograph than the brown and much larger females. For that reason, many birders and photographers call male Harriers “Gray Ghosts.”. One moment they’re in your viewfinder, the next, they’re gone.