Avian Osteology

Species - Proximal End	mm

Sharp-shinned Hawk	21 - 28
Northern Pygmy-Owl	23 - 29
American Kestrel	24 - 27
Merlin	25 - 30
Flammulated Owl	25 - 30
Copper's Hawk	28 - 35
Burrowing Owl	31 - 37
Northern Saw-whet Owl	33 - 40
Northern Hawk Owl	33 - 42
Osprey	34 - 43
Peregrine Falcon	35 - 44
Western Screech-Owl	35 - 44
Swainson's Hawk	36 - 46
Northern Hawk Owl	36 - 46
Eastern Screech-Owl	37 - 42
Short-eared Owl	37 - 45
Barn Owl	37 - 48
Red-tailed Hawk	37 - 53
Boreal Owl	38 - 43
Prairie Falcon	38 - 46
Long-eared Owl	38 - 47
Northern Goshawk	39 - 46
Gyrfalcon	43 - 50
Rough-legged Hawk	46 - 53
Barred Owl	50 - 56
Ferruginous Hawk	50 - 58
Spotted Owl	51 - 57
Great Gray Owl	57 - 66
Snowy Owl	58 - 65
Golden Eagle	58 - 66
Bald Eagle	60 - 67
Great Horned Owl	61 - 68