One of the most breathtaking natural spectacles in the Sierra Nevada and foothills is to spy a hawk or eagle in flight.  These majestic creatures dominate the sky and provide an awesome display for all lucky enough to observe them.

Glossary:

Carpal = wrist or “wrist-like”
Cere = fleshy area between the beak and the face
Coverts = covering feathers
Dihedral = V-shape
Patagial = dark patch on leading edge of underside of the inner wing
Primaries = flight feathers attached to the “hand”
Rufous = rusty red in color
Secondaries = flight feathers attached to the ‘elbow”
Subterminal = stripe before the tip of the tail
Supercilium = line of feathers above the eye
Tarsi = part of the leg between the “knee” and the “foot”
Vermiculate = wavy lines

Osprey (Pandion haliaetus)

Length: 22 inches Wingspan: 54 inches
Large, narrow-winged hawk
Flies on flat wings with distinct kink at elbow
Wings taper to a rounded tip
Short hooked beak
White cap
Dark brown eyeline broadening behind eye
Dark brown nape, back and upperwings
Wings from below: flight feathers white barred with black, undersecondary coverts white and underprimary coverts black producing rectangular black mark at wrist
White chin, throat, breast and belly
Brown tail has a number of white bands
Hovers and then plunges into water after fish

White-Tailed Kite (Elanus leucurus)

Length: 14.5 inches Wingspan: 40 inches
Sexes similar
Medium-sized, graceful, long-winged hawk
Pointed wings
Long, squared-off tail
Short, dark, hooked beak
Red eye
Black upperwing coverts appear as black shoulder at rest
Often hovers and soars with wings held in a dihedral, or V-shape

Bald Eagle (Haliaeetus leucocephalus)

Length: 32 inches Wingspan: 80 inches
Sexes similar
Very large, broad-winged, broad-tailed hawk
Rounded wings
Thick, hooked bill
Plucks fish from water with talons

Adult:
White head and upper neck
White tail
Dark brown body plumage
Yellow bill

Northern Harrier (Circus cyaneus)

Length: 16.5 inches Wingspan: 42 inches
Medium-sized, long-winged, long-tailed hawk
Rounded wings, can appear pointed while gliding
White rump
Short, dark, hooked beak
Often courses low over marshes and fields on wings held in a strong dihedral, or V-shape
Flat face with owl-like facial disk

Adult male:
Pale gray body plumage, paler on underparts
Darker gray head
Black tips to flight feathers, especially noticeable on the outer primaries
Narrow dark bars on tail

Adult female:
Buff underparts with darker streaks on breast, belly, and underwing coverts
Dark barring on flight feathers most visible from below
Dark patch on inner wing created by dark secondaries and dark secondary covert
Dark brown above
Narrow barring on tail

Sharp-Shinned Hawk (Accipter striatus)

Length: 10.5 inches Wingspan: 21 inches
Sexes similar, but females much larger
Small, broad-winged, long-tailed hawk
Short, dark, hooked beak
Long, narrow tarsi
Short, rounded wings
Long tail is squared-off at tip with prominent corners
Typically flies with several quick snappy wingbeats and a short glide, but also soars
Small rounded head does not project far beyond wings when soaring

Adult:
Red eye
Black cap
Blue-gray back and upperwings
White breast, belly and underwing coverts marked by fine, thin, reddish bars
White undertail coverts
Tail, blue gray above and pale below, barred with black bands
Flight feathers, blue-gray above and pale below, with dark bars

Cooper’s Hawk (Accipter cooperii)

Length: 15.5 inches Wingspan: 28 inches
Sexes similar, but females much larger
Medium-sized, broad-winged, long-tailed hawk
Short, dark, hooked beak
Long, thick tarsi appear short at rest because they are usually covered by belly feathers
Short, rounded wings
Very long tail is rounded at tip
Often flies with several quick wingbeats and a short glide, but also soars
Large angular head projects far beyond wings when soaring

Adult:
Red eye
Black cap
Blue-gray back and upperwings
White breast, belly and underwing coverts marked by fine, thin, reddish bars
White undertail coverts
Tail, blue gray above and pale below, barred with black bands
Flight feathers, blue-gray above and pale below, with dark bars

Northern Goshawk (Accipter gentiles)

Length: 19 inches Wingspan: 42 inches
Sexes similar, but females much larger
Medium-sized, broad-winged, long-tailed hawk
Short, dark, hooked beak
Rounded wings
Long tail rounded at tip
Flies with several flaps and short glide, also soars frequently
Short, dark, hooked beak
Long, very thick tarsi appear short at rest

Adult:
Red eye
Blackish head and face with bold white supercilium
Gray back and upperwings
Pale gray chin, throat, breast, underwing coverts and belly finely vermiculate
White undertail coverts
Tail dark blue-gray above and pale below, barred with dark bands
Flight feathers dark blue-gray above and pale below, barred with black

Red-Shouldered Hawk (Buteo lineatus)

Length: 16 inches Wingspan: 40 inches
Sexes similar
Short, dark, hooked beak
Large, fairly long-tailed, broad-winged hawk
Pale, translucent crescent at base of primaries

Adult:
Brown head
Reddish breast and underwing coverts
Pale belly barred heavily with reddish
Reddish lesser uppersecondary coverts appear as reddish shoulder at rest
Flight feathers dark above with white barring
Flight feathers pale below with dark barring
Dark tail has several narrow white bars
Florida birds (B. l. extimus) are paler about the head and have much paler breasts
California (B. l. elegans) and Texas (B. l. texanus) birds are much richer red

Swainson’s Hawk (Buteo swainsoni)

Length: 18 inches Wingspan: 49 inches
Sexes similar
Short, dark, hooked beak
Large, broad-winged, broad-tailed hawk
Very long-winged for a Buteo, with wings tapering noticeably at the tip

Light morph adult:
Gray-brown head
White chin patch
Reddish breast
White belly and underwing coverts
Dark flight feathers with faint barring
Dark brown back and upperwing
Gray tail, dark above and pale below, barred with narrow dark bars

Dark morph adult:
Dark brown head, back and upperwing
Underwing coverts often quite rufous
Flight feathers dark with barring, but paler than underwing coverts
Deep reddish brown breast with brownish barring below
Pale undertail coverts

Red-Tailed Hawk (Buteo jamaicensis)

Length: 18 inches Wingspan: 48 inches
Short, dark, hooked beak
Large, broad-winged, broad-tailed hawk
Immatures have notably narrower wings and tail, and appear slimmer
Dark patagial mark on underwing, present on all ages and races, is unique
Blocky translucent area in outer primaries
Flies with a dihedral, or V-shape
Extraordinary geographic variation

Light morph adult:
Brown head, nape, back, and upperwings
White chin, throat, breast, and belly
Dark belly band formed by vertical streaks in band across belly
White underwings have dark carpal bar on leading edge, dark outer primary tips and a dark trailing edge and are otherwise pale with dark bars on the flight feathers on all but the outermost primaries
Tail appears brick red above and pink below
Breast and back pattern vary with geography, with some birds being intermediate between light and dark morphs

Dark morph adult:
Wholly dark chocolate underparts, upperparts and underwing coverts with no apparent patagial mark
Pale underside to primaries and secondaries like light morph birds being pale with dark tips and dark bars on the flight feathers
Tail appears brick red above and pink below (like light morph adult)
Breast and back pattern vary with geography, with some birds being intermediate between light and dark morphs

Ferruginous Hawk (Buteo regalis)

Length: 20 inches Wingspan: 54 inches
Sexes similar
Short, dark, hooked beak
Large, broad-winged, broad-tailed hawk
Extremely long gape extends to below eye
Legs feathered to toes

Light morph adult:
Pale head, neck, breast, and belly
Variable rufous mottling on underwing coverts
Rufous leg coverts
Tail appears gray, rufous or whitish above and pale below
Gray or blue-gray upperwings have rufous upperwing coverts

Dark morph adult:
Entirely dark-brown body plumage
Undersides of flight feathers are pale without barring
White comma in outermost underwing coverts
Tail like light morph adult

Rough-Legged Hawk (Buteo lagopus)

Length: 19 inches Wingspan: 52 inches
Long, broad, rounded wings
Hooked beak
Broad tail
Yellow legs and cere
Sometimes hovers in flight
Wings held in slight dihedral

Dark morph adult:
Very dark plumage
Flight feathers barred and paler than wing linings
Dark trailing edge to flight feathers
Dark wrist
Broad, dark, subterminal band on tail
Female has white base to tail; male has dark tail with thin paler bars

Light morph adult:
Wide, dark, subterminal tail band
Upperparts dark brown with some mottling
Dark wrist contrasting with mottled wing linings and paler flight feathers
Females have darker bellies than males; males have darker breasts

Golden Eagle (Aguila chrysaetos)

Length: 32 inches Wingspan: 78 inches
Very large, broad-winged, broad-tailed hawk
Sexes similar
Short, dark, hooked beak with yellow cere

Adult:
Golden feathering on nape
Plumage almost entirely dark brown, without white in underwing coverts
Two pale brown median tail bands
Golden band on upperwing coverts

 

Credits: 

Cooper’s Hawk (R. Hays Cummins, Miami University of Ohio);  Ferruginous Hawk (Jim Watson, FerruginousHawk.org); Golden Eagle (Michel Claveau); Bald Eagle (Smithsonian Institution); Red-Shouldered Hawk (Carolina Raptor Center); Swainson’s Hawk (Dr. Thomas Haggerty, University of Northern Alabama); Northern Goshawk (Phil Detrich, USFWS); Northern Harrier (Michel Claveau); Osprey (Phenix Project, Brookhaven National Laboratory); Red-Tailed Hawk (Tam Stuart); Rough-Legged Hawk (Montana Raptor Conservation Center); Sharp-Shinned Hawk (Brandy Chloe – webshots.com); White-Tailed Kite (Cox of dphotos.com)