Hawkwatcher’s Helper: Identifying Bald Eagles and other Diurnal Raptors

HAWKWATCHER’S HELPER

 

A Photographic Identification Guide to the

Diurnal Raptors

of the Lower Susquehanna River Watershed


WHERE TO OBSERVE DIURNAL RAPTORS

One can study diurnal raptors almost anywhere in the Lower Susquehanna River Watershed.  Vultures can be seen cruising the skies in search of roadkill and other carrion.  Red-tailed Hawks and American Kestrels inhabit low-intensity agricultural lands.  Cooper’s Hawks have in recent years adapted to suburban life.  Ospreys and Peregrine Falcons nest along the Susquehanna.  And then there are the Bald Eagles, which again nest not only along the river, but in upland areas as well.  Beginning in November each year, a visit to the lower Susquehanna offers an opportunity to examine our national emblem in abundance, particularly at Conowingo Dam where a hundred birds or more often gather during late fall and early winter.  But without a doubt, the best time to learn diurnal raptor identification is during the spectacular autumn migrations when their numbers and variety are at their maximum.  It is during this time that an observer has the opportunity to compare the familiar species with those that are uncommon or are not likely to be encountered during other times of the year.

Eagle watching on the Susquehanna River at Conowingo Dam
Enthusiasts travel hundreds of miles to observe and photograph Bald Eagles at Conowingo Dam (where U.S. Route 1 crosses the Susquehanna River at Rising Sun, MD).  Eagles are most numerous from mid-November through early winter.  Another concentration in mid-spring may include both non-breeding eagles from the lower Susquehanna/upper Chesapeake region and post-breeding wanderers from nesting areas in southern states, particularly Florida.

To save energy while migrating, many raptors, particularly vultures and Broad-winged Hawks, seek out thermal updrafts (air rising above surfaces heated by the sun) to soar upon and gain altitude before gliding away.  Birds using this tactic can be observed from almost any location with an unobstructed view of the sky.  A hill or a rooftop situated along the birds’ flightpath will often suffice.  If you keep a close eye on the skies of the Lower Susquehanna River Watershed during the month of September, you stand a pretty good chance of seeing at least one “kettle” of Broad-winged Hawks passing by—even from your own home!

Migrating Broad-winged Hawks soaring in a thermal updraft to gain altitude.
Soaring Broad-winged Hawks circle in a thermal updraft to gain altitude on a September day.  Solar heating of south-facing hillsides, parking lots, and other surfaces creates the columns of rising air that these birds are so adept at locating during their autumnal flights.
Broad-winged Hawks Glide Away from the Top of a Thermal Updraft
After ascending, “Broad-wings” stream away from the top of the warm air column and continue off to the southwest, gliding slowly down to the lower reaches of yet another updraft to repeat the process.  Broad-winged Hawks migrating from the northeast make a long trek toward the Houston, Texas, area, then turn due south along the Gulf of Mexico on their way to the tropics for winter.

More often though, migrating raptors seeking to save energy will utilize the updrafts created by winds striking the slopes of the region’s numerous ridges.  These northeast-to-southwest-oriented ridge lines deflect skyward the horizontal flow of the northwest winds that often blow during the days that follow the passage of the cold fronts that motivate birds to move south in fall.  This linear system of rising air creates a network of highway-like “microflyways” that just happen to facilitate travel in the direction many raptors want to go—southwest.  To expedite their journey and expend less energy, opportunistic fliers follow these routes for at least a portion of their trip—entering and exiting at will.  On an ideal day, the raptor traffic can be quite heavy along one or more of these “highways”, much to the delight of any observer fortunate enough to be positioned at a lookout atop a ridge in their path.

Eagles gliding and soaring on wind-generated updrafts along the slopes of ridges.
Eagles migrating in a southwest direction can save energy and travel great distances by gliding and soaring on the updrafts generated as northwest winds strike the slopes of the northeast-to southwest-oriented ridges of the Lower Susquehanna River Watershed.

Each raptor species, being a bird of prey, is at the top of its food chain and, as such, can be a good indicator of the health of the ecosystems supporting the links in that chain.  It is therefore beneficial to monitor the population trends of raptors as indicators of environmental health.  Hawk counting got its start at Hawk Mountain Sanctuary in 1935 when Maurice Broun began keeping daily records of the migrating raptors seen each autumn.  Hawk Mountain’s data helped reveal the declines of the Osprey, Bald Eagle, and Peregrine Falcon during the 1950s and 1960s due, at least in part, to the effects of D.D.T.  Today, there are sites all over North America where official hawk counts are conducted.  To enumerate the birds migrating along the raptor “highways” of the Lower Susquehanna River Watershed and nearby areas of the Schuylkill River watershed (Hawk Mountain and Blue Mountain Route 183), observers have discovered many advantageous lookouts from which to see moving birds.  Eight of the best are plotted on the map which follows, including four where official counts are currently conducted each autumn.

Migratory raptor observation locations in and near the Lower Susquehanna River Watershed
Locations in and near the Lower Susquehanna River Watershed for watching autumn flights of migrating vultures, ospreys, eagles, harriers, hawks, and falcons.  (NASA Earth Observatory base image)

RIDGE AND VALLEY PROVINCE (SITES 1-5)

#1—Waggoner’s Gap Hawk Watch*—PA Route 74 north of Carlisle, PA

Excellent autumn flights, particularly on days with winds from the northwest.  Fewer birds but closer looks on southerly winds.  Golden Eagles from late October through November.

Waggoner's Gap Hawk Watch
Waggoner’s Gap Hawk Watch atop Blue Mountain.

#2—Second Mountain Hawk Watch*—Fort Indiantown Gap, PA

Good autumn flights with best numbers on southwest winds—possibly due in part to crossovers from Blue Mountain.  The access road can be rough, but observers can park right next to the lookout—no hiking.

Second Mountain Hawk Watch
Second Mountain Hawk Watch offers viewing from alongside the parking area…
Second Mountain Hawk Watch
… but you may need a rugged vehicle to get there.

#3—Hawk Mountain Sanctuary*—Kempton, PA

Excellent autumn flights, particularly on days with winds from the northwest.  Museum and interpretive programs offered.  Official counters on duty throughout the fall season and sometimes during spring flights.  Very crowded during peak autumn weekends.  The hike to North Lookout atop Blue Mountain (often called Kittatinny Ridge at Hawk Mountain and at points to the east) is almost a mile.  Admission fee.

  #4—Cove Mountain Hawk Watch—Appalachian Trail, Shermans Dale, PA

A difficult to access site in a gas pipeline right-of-way along the Appalachian Trail.  Good autumn flights.

 #5—Blue Mountain Route 183 Hawk Watch—Strausstown, PA

Good autumn flights, particularly on northwest winds.  Many of the birds counted at nearby Hawk Mountain continue following updrafts along Blue Mountain to also pass this location.

PIEDMONT PROVINCE (SITES 6-8)

  #6—Governor Dick Fire Tower—Clarence Schock Memorial Park, Mount Gretna, Lebanon County, PA

“Furnace Hills” location just east of the former Cornwall Fire Tower Hawk Watch site.  Observations of autumn and spring migrations through the Piedmont highlands can be made from the top of the sixty-six-foot-tall tower or from ground level in the forest clearing that surrounds it.

Governor Dick Fire Tower at Clarence Schock Memorial Park
For those using binoculars, a cage installed on the Governor Dick Fire Tower to prevent rappelling can make scanning the skies for birds a challenge.  Choosing a suitable location on the grounds surrounding the tower may offer better observing conditions.
Former Cornwall Fire Tower Hawk Watch Site in the Furnace Hills
A view from atop Governor Dick Fire Tower of the “Furnace Hills” to the east.  The Lancaster County Bird Club conducted an autumn hawk count at the former Cornwall Fire Tower location where the cluster of antennas stands today.

#7—Conewago Falls—Susquehanna River at Collins Road, Falmouth, PA

Viewing from amid the “pothole rocks” in the narrow section of river downstream of Three Mile Island.  This site is accessible only when the river stage at Harrisburg, PA, is below four feet.  During spring and autumn, fair numbers of birds are seen either following the river or the diabase ridge that it intersects here.  Nesting Ospreys, Bald Eagles, and Peregrine Falcons in spring and summer.  Riverine birds year-round.

The diabase "Pothole Rocks" at Conewago Falls on the Susquehanna.
The diabase “pothole rocks” at Conewago Falls on the Susquehanna River.  Hawkwatchers with a knack for fishing can multitask here.

#8—Rocky Ridge County Park Hawk Watch*—northeast of York, PA

A site in a powerline right-of-way with a viewing platform and interpretive displays.  One of the few locations with good autumn flights on northeast winds.

Rocky Ridge County Park Hawk Watch
Rocky Ridge County Park Hawk Watch observation platform.  The cluster of masonry structures in the distance are the electrical generating stations at Brunner Island and Three Mile Island.

Further afield, these regional hawk watch sites are worth a visit:

IN THE RIDGE AND VALLEY PROVINCE

Bake Oven Knob*—Lehigh/Carbon Counties, PA

Just northeast of Hawk Mountain Sanctuary on Blue Mountain/Kittatinny Ridge.

Bald Eagle Mountain-Eagle Field*—State College, PA

Spectacular Golden Eagle flights in fall, especially on northwest winds.

Jack’s Mountain Hawk Watch*—Mifflin County, PA

Good autumn flights, best on southeast winds.

Little Gap Hawk Watch*—north of Allentown, PA

Site on Blue Mountain/Kittatinny Ridge.  Excellent flights in fall, particularly on northwest winds.

Raccoon Ridge Hawk Watch*—Worthington State Forest, NJ

Site on Blue Mountain/Kittatinny Ridge northeast of Delaware Water Gap.  Excellent flights in fall, particularly on northwest winds.

Stone Mountain Hawk Watch*—Huntingdon/Mifflin Counties, PA

Good autumn flights, best on northwest and west winds.

Tussey Mountain Hawk Watch*—State College, PA

Good spring and fall flights.  Golden Eagle movements on southerly winds in spring.

IN THE APPALACHIAN PLATEAUS PROVINCE

Allegheny Front Hawk Watch*—Bedford/Somerset Counties, PA

Autumn flights on east winds.  Golden Eagles from late October through November.

Franklin Mountain Hawk Watch*—Delaware-Otsego Audubon Society Sanctuary, Oneonta, NY

Site overlooking the Susquehanna River valley from along the western edge of the Catskill Mountains.  Autumn flights including Golden Eagles from late October through November.

IN THE PIEDMONT PROVINCE

Ashland Nature Center*—Hockessin, DE

Reliable autumn flights, even on northeast winds.  Red-shouldered Hawks in October.

Hawk Watch Hill at the Ashland Nature Center
Hawk Watch Hill at the Ashland Nature Center.

Cromwell Valley Park*—Baltimore County, MD

Just south of Loch Raven Reservoir.  Good autumn flights including Broad-winged Hawks in September.

Rose Tree Park Hawk Watch*—Media, Delaware County, PA

Good autumn flights including Broad-winged Hawks in September.

Militia Hill Hawk Watch*—Fort Washington, PA

Good autumn flights including Broad-winged Hawks in September.

Southern Chester County Hawk Watch at Bucktoe Creek Preserve*—Avondale, PA

Spring and fall flights.  Kite and shorebird watch in late May/early June.  No official autumn count since October of 2020.

IN THE ATLANTIC COASTAL PLAIN

Cape Henlopen Hawk Watch*—Lewes, DE

Site atop a beachside World War II-era bunker in Cape Henlopen State Park.  Excellent autumn raptor flights—plus sea watching for birds and cetaceans.  Falcons from late September into October.  Some birds arrive after coming south along the western shore of Delaware Bay; others make landfall after crossing the mouth of the bay from Cape May.

Cape Henlopen Hawk Watch
Cape Henlopen Hawk Watch viewing deck on a World War II-era defense bunker.

Cape May Hawk Watch*—Cape May Point, NJ

Site with a viewing platform adjacent to the lighthouse parking area in Cape May Point State Park.  World-renowned autumn birding and hawk watching.  Northwest winds bring the southbound raptors right down the beach.  Falcons from late September into October.  Birds of all kinds get stalled and “pile up” around Cape May before attempting to cross Delaware Bay.  Something unusual always seems to show up.

Fort Smallwood Park*—Pasadena, Anne Arundel County, MD

Site along the western shore of Chesapeake Bay at the mouth of the Patapsco River.  Spring migration on southwest winds.

Kiptopeke Hawk Watch*—Kiptopeke State Park, VA

Site on Chesapeake Bay near the southern tip of the Delmarva Penninsula.  Phenomenal flights of raptors and other migratory birds in autumn.  Rarities surprise observers with some regularity.

IN THE BLUE RIDGE MOUNTAINS (SOUTH MOUNTAIN) PROVINCE

Snicker’s Gap Hawk Watch*—Clarke/Loudoun Counties, VA

Site where VA Route 7 crosses the Blue Ridge Mountains.  Good autumn flights.

Washington Monument State Park Hawk Watch*—Boonsboro, MD

Hawk watching from the top of a stone tower.  Spring and fall flights.

* Locations staffed by official counters during the fall and/or spring season.  Click the hawk watch name to access travel directions, site information, and the latest count data from the Hawk Migration Association of North America’s hawkcount.org website.


TOPOGRAPHY OF A DIURNAL RAPTOR IN FLIGHT

Topography of Diurnal Raptor in Flight


Order-Accipitriformes

(New World Vultures, Ospreys, Eagles, Kites, Harriers, and Hawks)

 


Family-Cathartidae

(New World Vultures)

Cathartidae (New World Vultures): Black Vulture and Turkey Vulture


BLACK VULTURE (Coragyps atratus)

Raptor/Vulture Identification: Black Vulture
A Black Vulture.  (October)
Raptor/Vulture Identification: Black Vulture
Black Vultures have silvery undersides on their primary feathers.  Quick choppy wingbeats and a short tail are clues to help identify this species even at a considerable distance.  (November)

BLACK VULTURE (Coragyps atratus) Adult

Raptor/Vulture Identification: Black Vulture
An adult Black Vulture.  Note the yellow tip on the black bill.  (November)
Raptor/Vulture Identification: Black Vulture
A Black Vulture undergoing molt of the flight feathers during autumn is an adult bird.  (September)

BLACK VULTURE (Coragyps atratus) Hatch-Year (Juvenile)

Raptor/Vulture Identification: Black Vulture
A hatch-year/juvenile Black Vulture.  The all-dark bill is characteristic of a young bird.  The white shafts and silvery undersides of the primary feathers are shared traits among all age classes.  (September)

TURKEY VULTURE (Cathartes aura)

Raptor/Vulture Identification: Turkey Vulture
Soaring and gliding Turkey Vultures of all age classes are easily recognized by their up-tilted wing posture often referred to as a dihedral.  As a means of adjusting and maintaining their flight trajectory, “T.V.s” are frequently observed rocking from side to side on outstretched wings.

TURKEY VULTURE (Cathartes aura) Adult

Raptor/Vulture Identification: Turkey Vulture
An adult Turkey Vulture is easily recognized by its red head and yellow-tipped bill.  (January)
Raptor/Vulture Identification: Turkey Vulture
An adult Turkey Vulture.  Note the silvery underside of the entire set of flight feathers, a field mark shared with all age classes.  (November)
Raptor/Vulture Identification: Turkey Vulture
The angle of the sunlight illuminating the silvery undersides of a Turkey Vulture’s flight feathers can dramatically alter the bird’s appearance.  (November)
Raptor/Vulture Identification: Turkey Vulture
An adult Turkey Vulture.  (December)

TURKEY VULTURE (Cathartes aura) Hatch-Year (Juvenile)

Raptor/Vulture Identification: Turkey Vulture
Hatch-year/juvenile Turkey Vultures have a gray/black head, a black bill, and a full set of fresh juvenile flight feathers.  (September)
Raptor/Vulture Identification: Turkey Vulture
A hatch-year/juvenile Turkey Vulture.  Note the neat and clean appearance presented by the absence of molt in the flight feathers.  (September)
Raptor/Vulture Identification: Turkey Vulture
A hatch-year/juvenile Turkey Vulture.  (September)

TURKEY VULTURE (Cathartes aura) Second-Year (Immature)

Raptor/Vulture Identification: Turkey Vulture
A second-year/immature Turkey Vulture showing traces of red coloration in the head, a paler bill color than a juvenile bird, and replacement of some of the juvenile flight feathers.  (October)

Family-Pandionidae

(Osprey)

 


OSPREY (Pandion haliaetus)

Raptor Identification: Osprey
Osprey are easily recognized by their long slim wings and dark carpal (wrist) patches.  (August)
Raptor Identification: Osprey
While flapping, gliding, and soaring, an Osprey’s wings appear to be held up by the wrists, creating an M-shaped flight posture.  (October)

OSPREY (Pandion haliaetus) Adult

Raptor Identification: Osprey
An after-second-year/adult Osprey undergoing molt.  Because first-year/juvenile Osprey retain their first set of flight feathers until well after their first autumn migration, then tend to remain on the wintering grounds and not migrate north during their second year, Osprey seen losing and replacing rectrices and remiges while in the Lower Susquehanna River Watershed are generally regarded as adult birds in at least their third year of life.  (August)
Raptor Identification: Osprey
An after-second year/adult Osprey molting and replacing flight feathers.  (September)

OSPREY (Pandion haliaetus) Hatch-Year (Juvenile)

Raptor Identification: Osprey
During autumn migration, Osprey with unstreaked white breasts and no evidence of molt in the flight feathers are often hatch-year/juvenile birds.  (September)
Raptor Identification: Osprey
Pale edges on the upperwing coverts indicate this is a hatch-year/juvenile Osprey, but note the presence of light streaking on the breast.  (October)
Raptor Identification: Osprey
Neat and clean with no signs of molt in the flight feathers, a possible hatch-year/juvenile Osprey.  (October)

Family-Accipitridae

(Eagles, Kites, Harriers, and Hawks)

Accipitridae (Eagles, Kites, Harriers, and Hawks)


BALD EAGLE (Haliaeetus leucocephalus) Adult (Definitive Plumage)

Raptor Identification: Bald Eagle
An adult Bald Eagle.  (August)
Raptor Identification: Bald Eagle
An adult Bald Eagle in definitive plumage undergoing an annual molt.  (August)
Raptor Identification: Bald Eagle
An adult Bald Eagle in definitive plumage.  (September)
Raptor Identification: Bald Eagle
An adult Bald Eagle in definitive plumage (top) and a Broad-winged Hawk (bottom). (September)
Raptor Identification: Bald Eagle
Note the flat board-like flight posture of the wings displayed by these soaring Bald Eagles.  (October)
Raptor Identification: Bald Eagle
An adult Bald Eagle in definitive plumage.  (October)
Raptor Identification: Bald Eagle
An adult Bald Eagle in definitive plumage.  (October)
Raptor Identification: Bald Eagle
When observed as mated pairs, Bald Eagles, like other birds of prey, often reveal noticeable sexual dimorphism, the female (left) being larger than the male (right).  (November)

BALD EAGLE (Haliaeetus leucocephalus) Hatch-Year (Juvenile)

Raptor Identification: Bald Eagle
A hatch-year/juvenile Bald Eagle.  (August)
Raptor Identification: Bald Eagle
A hatch-year/juvenile Bald Eagle.  Note the neat and clean molt-free appearance of the flight feathers, the bright white axillaries (“wing pits”), and the dark belly; all are typical field marks of first-year birds.  (September)
Raptor Identification: Bald Eagle
A hatch-year/juvenile Bald Eagle prominently showing “windows” in the innermost primary flight feathers.  At a distance, these markings may create the illusion that the bird is undergoing molt, indicating that the eagle is older than a first-year bird.  Primary “windows” have prominent dark borders on older birds, those in their second and third years.  (October)
Raptor Identification: Bald Eagle
The same hatch-year/juvenile Bald Eagle as shown previously.  Again, notice the “windows” on the innermost primaries.  (October)
Raptor Identification: Bald Eagle
A hatch-year/juvenile Bald Eagle.  During the first three years life, Bald Eagles show extensive areas of white on the underside of their wings, densest on the linings toward the leading edge and in the “wing pits”.  (November)
Raptor Identification: Bald Eagle
Beware!  A non-adult Bald Eagle can easily be mistaken for a Golden Eagle.  This hatch-year/juvenile Bald Eagle gave the illusion of being a Golden Eagle while gliding by a hawk watch station (left)…until, moments later, it was seen soaring above the lookout (right).  Note the extensive areas of white in the wing linings and in the “wing pits”, key field marks for identifying Bald Eagles during their first three years.  (November)
Raptor Identification: Bald Eagle
A hatch-year/juvenile Bald Eagle.  (December)

BALD EAGLE (Haliaeetus leucocephalus) Second-Year (Immature Basic I)

Raptor Identification: Bald Eagle
A second-year/Basic I immature Bald Eagle.  Birds at this age are also known as “White Belly I” Bald Eagles.  (August)
Raptor Identification: Bald Eagle
A second-year/Basic I immature Bald Eagle.  Extensive molt of the flight feathers (replacement of long juvenile remiges with shorter primaries and secondaries) gives a bird at this age a messy, ragged appearance.  (October)
Raptor Identification: Bald Eagle
A second-year/Basic I immature Bald Eagle.  Note the dark borders surrounding the “windows” on the innermost primaries.  (October)
Raptor Identification: Bald Eagle
A second-year/Basic I immature Bald Eagle (left) and an adult Bald Eagle in definitive plumage (right).  (October)
Raptor Identification: Golden and Bald Eagles
A second-year/Basic I immature Golden Eagle (left) and a second-year/Basic I immature Bald Eagle (right).  Note how the shorter head projection of the Golden Eagle gives the bird a long-tailed appearance while the head and tail on the Bald Eagle seem equal in length.  This is a prime differentiating field mark for the two species in all age classes.  (November)
Raptor Identification: Bald Eagle
A second-year/Basic I immature Bald Eagle.  Note the retained juvenile secondaries (the longer flight feathers that give the trailing edge of the wings a jagged appearance).  The “windows” on the innermost primaries have more extensive dark borders than those of hatch-year/juvenile Bald Eagles.  (November)
Raptor Identification: Bald Eagle
Two second-year/Basic I immature Bald Eagles.  (November)
Raptor Identification: Bald Eagle
A second-year/Basic I immature Bald Eagle photographed in light reflected by snow cover.  (December)

BALD EAGLE (Haliaeetus leucocephalus) Third-Year (Immature Basic II)

Raptor Identification: Bald Eagle
A third-year/Basic II immature Bald Eagle.  Birds at this age are also known as “White Belly II” or “Osprey Face” Bald Eagles.  (November)
Raptor Identification: Bald Eagle
A third-year/Basic II immature Bald Eagle.  Birds at this age begin replacing white feathers in the wing linings, in the “wing pits”, and on the belly with brown plumage.  Gradual replacement of the crown and throat feathers with white plumage gives many birds at this age an Osprey-like face pattern.  (November)
Raptor Identification: Bald Eagle
A third-year/Basic II immature Bald Eagle (bottom) with a second-year/Basic I immature Bald Eagle (top).  (November)
Raptor Identification: Bald Eagle
A third-year/Basic II immature Bald Eagle (top) with a second-year/Basic I immature Bald Eagle (bottom).  As seen here, birds in both of these age classes typically have white back feathers.  (November)
Composite image of Bald Eagles as they typically appear during November in each of their first three years. 
Composite image of Bald Eagles as they typically appear during November in each of their first three years.

BALD EAGLE (Haliaeetus leucocephalus) Fourth-Year (Immature Basic III)

A fourth-year/Basic III immature Bald Eagle
A fourth-year/Basic III immature Bald Eagle.  (September)
Raptor Identification: Bald Eagle
A fourth-year/Basic III immature Bald Eagle (right) and an adult Bald Eagle in definitive plumage (left).  This particular fourth-year bird still has a thin dark line through the eye on an otherwise all-white head.  Note the dark border surrounding the white tail and the abundance of retained white feathers in the wings and on the belly.  (November)
Raptor Identification: Bald Eagle
A fourth-year/Basic III immature Bald Eagle (far right).  The dark line through the eye and the yellow bill are typical of a bird this age.  The tail shows a dark terminal band, wider than the dark tips that one might expect on a fifth-year /Basic IV Bald Eagle.  (November)
A fourth-year/Basic III immature Bald Eagle
A fourth-year/Basic III immature Bald Eagle.  (November)

BALD EAGLE (Haliaeetus leucocephalus) Fifth-Year (Immature Basic IV)

Raptor Identification: Bald Eagle
A fifth-year/Basic IV immature Bald Eagle.  Note the dark tips on the rectrices (tail feathers) and the white head.  Both of these traits can easily be overlooked on a passing bird.  (October)
Raptor Identification: Bald Eagle
A probable fifth-year/Basic IV immature Bald Eagle.  Note the retained white body feathers on this particular individual.  (October)
Raptor Identification: Bald Eagle
A probable fifth-year/Basic IV immature Bald Eagle.  In addition to dark tips on the rectrices, some birds at this age may show signs of a dark line through or behind the eye.  (November)
Raptor Identification: Bald Eagle
A fifth-year/Basic IV immature Bald Eagle.  (November)
Raptor Identification: Bald Eagle
A closer look at the spread tail of the fifth-year/Basic IV immature Bald Eagle shown in the preceding image.  Note the trace of dark color on the tips of the outer feathers and remnants of a wider dark band on the innermost ones.  (November)

BALD EAGLE (Haliaeetus leucocephalus) Sixth-Year (Adult)

Raptor Identification: Bald Eagle
A bird that may be exactly five years old, a sixth-year/adult Bald Eagle nearing definitive plumage.  Note the retention of at least one black-edged rectrix (tail feather).  (March)

GOLDEN EAGLE (Aquila chrysaetos)

Raptor Identification: Golden Eagle
The gilded head plumage of a Golden Eagle is visible in all age classes.

GOLDEN EAGLE (Aquila chrysaetos) After-Third-Year

Click the “Golden Eagle Aging Chart” tab at the top of this page to learn more about the molt sequence of Golden Eagles.

Raptor Identification: Golden Eagle
An after-third-year Golden Eagle.  (November)
Raptor Identification: Golden Eagle
An after-third-year Golden Eagle.  (November)

GOLDEN EAGLE (Aquila chrysaetos) Third -Year (Immature Basic II)

Click the “Golden Eagle Aging Chart” tab at the top of this page to learn more about the molt sequence of Golden Eagles.

Raptor Identification: Golden Eagle
A probable third-year/Basic II immature Golden Eagle.  (November)
Raptor Identification: Golden Eagle
A probable third-year/Basic II immature Golden Eagle.  Note the retained juvenile secondaries (the longer flight feathers that create a ragged appearance along the trailing edge of the wings) on this molting bird.  (November)

GOLDEN EAGLE (Aquila chrysaetos) Before-Third -Year

Click the “Golden Eagle Aging Chart” tab at the top of this page to learn more about the molt sequence of Golden Eagles.

Raptor Identification: Golden Eagle
A before-third-year Golden Eagle.  (October)
Raptor Identification: Golden and Bald Eagles
A before-third-year Golden Eagle (left) and a hatch-year/juvenile Bald Eagle (right).  Note the Bald Eagle’s proportionately longer head projection when compared to the Golden Eagle.  (November)
Raptor Identification: Golden and Bald Eagles
Non-adult Golden Eagles including the before-third-year bird seen here (left) often have conspicuous white bases on the primary and/or secondary flight feathers, while Bald Eagles during their first three years of life (right) have varying amounts of white mottling concentrated mostly in the linings toward the leading edge of the wings.  Note too the extensive white mottling on the belly of this third-year/Basic II immature Bald Eagle.  (November)
Raptor Identification: Golden Eagle
A before-third-year Golden Eagle.  (November)
Raptor Identification: Golden Eagle
A before-third-year Golden Eagle.  (November)
Raptor Identification: Golden Eagle
A before-third-year Golden Eagle.  (November)

GOLDEN EAGLE (Aquila chrysaetos) Hatch-Year (Juvenile)

Raptor Identification: Golden Eagle
A hatch-year/juvenile Golden Eagle.  (November)

Click the “Golden Eagle Aging Chart” tab at the top of this page to learn more about the molt sequence of Golden Eagles.


SWALLOW-TAILED KITE (Elanoides forficatus)

Raptor/Kite Identification: Swallow-tailed Kite
Swallow-tailed Kites are unmistakable when seen with anything close to favorable viewing conditions.  These magnificent raptors nest in a greatly reduced breeding range that presently includes Florida, the Gulf States, and South Carolina.  They are very rare late-spring visitors in the Lower Susquehanna River Watershed.  This particular bird was found in poor health during the late winter on March 13, 2005, near Octoraro Creek in Lancaster County, Pennsylvania.  It subsequently died.  (Specimen in the Pennsylvania Game Commission collection at the Middle Creek Wildlife Management Area Visitor’s Center)

MISSISSIPPI KITE (Ictinia mississippiensis) 

Raptor Identification: Mississippi Kite
Mississippi Kites are recognized by their long, pointed wings and graceful flight.  (June)

MISSISSIPPI KITE (Ictinia mississippiensis) Adult

Raptor Identification: Mississippi Kite
An adult Mississippi Kite “feeding on the wing”.  Dragonflies and other large flying insects are a favorite food.  (May)  (Vintage 35 mm image)

MISSISSIPPI KITE (Ictinia mississippiensis) Second-Year (Immature)

Raptor Identification: Mississippi Kite
Second-year/immature Mississippi Kites.  (June)
Raptor Identification: Mississippi Kite
A second-year/immature Mississippi Kite.  A banded tail and gray underparts are typical of this age class.  (June)
Raptor Identification: Mississippi Kite
A second-year/immature Mississippi Kite in the early stages of juvenile flight feather replacement showing loss of a tail feather (retrix).  (June)
Raptor Identification: Mississippi Kite
A second-year/immature Mississippi Kite showing replacement of a juvenile tail feather with an all-dark adult retrix .  (June)
Raptor Identification: Mississippi Kite
The second-year/immature Mississippi Kite from the previous image feeding on a periodical cicada.  (June)
Raptor Identification: Mississippi Kite
A second-year/immature Mississippi Kite molting juvenile flight feathers.  (June)
Raptor Identification: Mississippi Kite
Second-year/immature Mississippi Kites feeding on periodical cicadas.  (June)

NORTHERN HARRIER (Circus hudsonius)

Raptor Identification: Northern Harrier
Silhouette of a Northern Harrier.  The dihedral flight posture of the narrow wings, the long tail, and the short head projection often make the “marsh hawk” an easy bird to identify.  (October)
Identifying Raptors: Northern Harrier
Long uptilted wings give the Northern Harrier a flight posture that is unique among the diurnal raptors of eastern North America.

NORTHERN HARRIER (Circus hudsonius) Adult

Raptor Identification: Northern Harrier
An adult male Northern Harrier.  Even at a considerable distance, the white rump patch can clinch the identification of this species in all plumages.  (October)
Raptor Identification: Northern Harrier
An adult male Northern Harrier, dorsal view.  (October)
Raptor Identification: Northern Harrier
An adult male Northern Harrier, ventral view.  (October)
Raptor Identification: Northern Harrier
An adult male Northern Harrier, known colloquially as a “gray ghost”.  (October)
Raptor Identification: Northern Harrier
An adult female Northern Harrier.  (October)
Raptor Identification: Northern Harrier
An adult female Northern Harrier.  Note the heavily streaked breast.  (October)

NORTHERN HARRIER (Circus hudsonius) Hatch-Year (Juvenile)

Raptor Identification: Northern Harrier
A hatch-year/juvenile Northern Harrier.  Note the cinnamon-rufous tint of the bird’s body plumage.  (September)
Raptor Identification: Broad-winged Hawk and Northern Harrier
A hatch-year/juvenile Northern Harrier (lower right) soaring with an adult Broad-winged Hawk (upper left).  (September)
Raptor Identification: Northern Harrier
A hatch-year/juvenile Northern Harrier.  When seen, the owl-like face and “headless hawk” flight posture are two good field marks.  Normally a graceful flier, a Northern Harrier may appear clumsy while flapping because of its long wings.  (October)
Raptor Identification: Northern Harrier
A hatch-year/juvenile Northern Harrier.  Note the pointed look of the wings while the bird is gliding.  (October)
Raptor Identification: Northern Harrier
A gliding hatch-year/juvenile Northern Harrier.  (October)

SHARP-SHINNED HAWK (Accipiter striatus)

Raptor/Accipiter Identification: Sharp-shinned Hawk vs. American Kestrel
A Sharp-shinned Hawk (right), the smallest of the North American accipitrids, tangles with an American Kestrel (left).

SHARP-SHINNED HAWK (Accipiter striatus) Adult

Raptor/Accipiter Identification: Sharp-shinned Hawk
A probable second-year/adult Sharp-shinned Hawk.  “Sharpies” often glide with an arched posture, their tails raised above the plane of the forward portion of the body.  (September)
Raptor/Accipiter Identification: Sharp-shinned Hawk
An adult Sharp-shinned Hawk.  (October)
Raptor/Accipiter Identification: Sharp-shinned Hawk
An adult Sharp-shinned Hawk.  A squared-off or notched tail is typical of all “Sharpies” in powered flight, as is a snappy set of wing beats between glides.   (October)
Raptor/Accipiter Identification: Sharp-shinned Hawk
An adult male Sharp-shinned Hawk.  When fully mature, all Accipiters have red eyes like this bird.  (November)

SHARP-SHINNED HAWK (Accipiter striatus) Hatch-Year (Juvenile)

Raptor/Accipiter Identification: Sharp-shinned Hawk
A hatch-year/juvenile Sharp-shinned Hawk showing short head projection and a squared-off tail with a notched appearance.   (September)
Raptor/Accipiter Identification: Sharp-shinned Hawk
A hatch-year/juvenile Sharp-shinned Hawk.  (September)
Raptor/Accipiter Identification: Sharp-shinned Hawk
A hatch-year/juvenile Sharp-shinned Hawk.  Note how the head barely projects beyond the wrists on this gliding bird.  (October)
Raptor/Accipiter Identification: Sharp-shinned Hawk
A hatch-year/juvenile Sharp-shinned Hawk. Note the yellow eyes, a field mark of “sharpies” in their first year of life.
Raptor/Accipiter Identification: Sharp-shinned Hawk
A hatch-year/juvenile Sharp-shinned Hawk.  (October)

COOPER’S HAWK (Accipiter cooperii) Adult

Raptor/Accipiter Identification: Cooper's Hawk
An adult Cooper’s Hawk.  The red eyes indicate that this bird is probably at least in its fourth year.  (January)
Raptor/Accipiter Identification: Cooper's Hawk
An adult Cooper’s Hawk early in its second year (still less than one year of age).  Reddish-brown markings are visible where juvenile feathers along the flanks and in the underwing coverts have been replaced.  There is not yet any sign of molt in the flight feathers.  Note that the well-worn juvenile rectrices (tail feathers) appear nearly equal in length on this particular individual.  (February)
Raptor/Accipiter Identification: Cooper's Hawk
An adult Cooper’s Hawk.  Note the long, rounded tail.  While in a glide, the head projects well forward of the wrists.  (October)
Raptor/Accipiter Identification: Cooper's Hawk
A soaring adult Cooper’s Hawk.  Note the double-notched appearance of the tail’s trailing edge created by the shorter outer tail feathers, a shape often reminiscent, when a bird is seen at this angle, of the top of a keystone.  (October)
Raptor/Accipiter Identification: Cooper's Hawk
An adult Cooper’s Hawk.  In a glide, the shorter outer tail feathers contribute to the rounded appearance of the compressed tail.  (October)
Raptor/Accipiter Identification: Sharp-shinned and Cooper's Hawks
An adult Sharp-shinned Hawk with slightly rounded corners on the tail (left) compared to the adult Cooper’s Hawk from the preceding image (right).  Note the heftier appearance of the protruding head and more tubular contour of the Cooper’s Hawk’s body and tail.  (October)
Raptor/Accipiter Identification: Cooper's Hawk
Note the slightly shorter outermost tail feathers on this adult Cooper’s Hawk.  In flight, particularly while soaring or gliding, they will cause the corners of the tail to appear notched or rounded.  The pale orange eye indicates that this bird is probably in its second or third year.  (December)

COOPER’S HAWK (Accipiter cooperii) Hatch-Year (Juvenile)

Raptor/Accipiter Identification: Cooper's Hawk
A hatch-year/juvenile Cooper’s Hawk showing both a central notch and rounded corners on its tail.  (September)
Raptor/Accipiter Identification: Cooper's Hawk
A hatch-year/juvenile Cooper’s Hawk.  Note the long wings and tail.  (September)
Raptor/Accipiter Identification: Cooper's Hawk
A hatch-year/juvenile Cooper’s Hawk.  While soaring with wings fully extended, this species often gives the impression of a flying cross.  (October)
Raptor/Accipiter Identification: Cooper's Hawk
A hatch-year/juvenile Cooper’s Hawk.  When soaring, the tail of this species appears especially large for the bird.  (November)
Raptor/Accipiter Identification: Cooper's Hawk
A hatch-year/juvenile Cooper’s Hawk.  Yellow eyes are diagnostic of juvenile accipiters.  (November)
Raptor/Accipiter Identification: Cooper's Hawk
A hatch-year/juvenile Cooper’s Hawk in the early stages of molt showing some gray adult feathers on its back.  (December)
Raptor/Accipiter Identification: Cooper's Hawk
A hatch-year/juvenile Cooper’s Hawk.  (December)

NORTHERN GOSHAWK (Accipiter gentilis) Hatch-Year (Juvenile)

Raptor/Accipiter Identification: Northern Goshawk
A hatch-year/juvenile Northern Goshawk.  Note the hefty barrel-chested appearance of this accipiter.  Goshawks at this age have a “dirty” appearance created by dense streaking on the breast that extends along the flanks into the undertail coverts.  (November)
Raptor/Accipiter Identification: Northern Goshawk
A hatch-year/juvenile Northern Goshawk.  (November)

RED-SHOULDERED HAWK (Buteo lineatus)

Raptor/Buteo Identification: Red-shouldered Hawk
The translucent wing panels on Red-shouldered Hawks of all age classes appear as crescent-shaped “windows” at the base of the primary wing feathers.

RED-SHOULDERED HAWK (Buteo lineatus) Adult

Raptor/Buteo Identification: Red-shouldered Hawk
A second-year/adult Red-shouldered Hawk molting juvenile rectrices and remiges.  (June)
Raptor/Buteo Identification: Red-shouldered Hawk
An adult Red-shouldered Hawk.  (January)
Raptor/Buteo Identification: Red-shouldered Hawk
An adult Red-shouldered Hawk.  (June)
Raptor/Buteo Identification: Red-shouldered Hawk
An adult Red-shouldered Hawk.  (September)
Raptor/Buteo Identification: Red-shouldered Hawk
An adult Red-shouldered Hawk.  (November)
Raptor/Buteo Identification: Red-shouldered Hawk
An adult Red-shouldered Hawk soaring.  (November)
Raptor/Buteo Identification: Red-shouldered Hawk
An adult Red-shouldered Hawk in a glide.  (November)
Raptor/Buteo Identification: Red-shouldered Hawk
An adult Red-shouldered Hawk in a glide.  (November)
Raptor/Buteo Identification: Red-shouldered Hawk
An adult Red-shouldered Hawk in powered flight.  (November)
Raptor/Buteo Identification: Red-shouldered Hawk
An adult Red-shouldered Hawk with a damaged rectrix.  (November)

RED-SHOULDERED HAWK (Buteo lineatus) Hatch-Year (Juvenile)

Raptor/Buteo Identification: Red-shouldered Hawk
A hatch-year/juvenile Red-shouldered Hawk soaring.  Note the translucent wing panels, crescent-shaped “windows” at the base of the primaries.  (August)

BROAD-WINGED HAWK (Buteo platypterus)

Raptor/Buteo Identification: Broad-winged Hawk
Migrating Broad-winged Hawks “kettling” on a thermal updraft.  (September)
Raptor/Buteo Identification: Broad-winged Hawk
Broad-winged Hawks gliding away to the southwest after gaining altitude in a column of rising warm air.  (September)

BROAD-WINGED HAWK (Buteo platypterus) Adult

Raptor/Buteo Identification: Broad-winged Hawk
A molting second-year/adult Broad-winged Hawk showing retained juvenile (longer) secondary flight feathers.  (September)
Raptor/Buteo Identification: Broad-winged Hawk
An adult Broad-winged Hawk.  (September)
Raptor/Buteo Identification: Broad-winged Hawk
An adult Broad-winged Hawk.  Note the translucent wing panels, with light visible throughout the primaries.  (September)
Raptor/Buteo Identification: Broad-winged Hawk
An adult Broad-winged Hawk.  (September)
Raptor/Buteo Identification: Broad-winged Hawk
A backlit adult Broad-winged Hawk.  Note the wing panels, translucence extending throughout the primaries.  (September)
Raptor/Buteo Identification: Broad-winged Hawk
An adult Broad-winged Hawk.  (September)

BROAD-WINGED HAWK (Buteo platypterus) Hatch-Year (Juvenile)

Raptor/Buteo Identification: Broad-winged Hawk
A hatch-year/juvenile Broad-winged Hawk.  (September)
Raptor/Buteo Identification: Broad-winged Hawk
A hatch-year/juvenile Broad-winged Hawk.  (September)
Raptor/Buteo Identification: Broad-winged Hawk
A hatch-year/juvenile Broad-winged Hawk.  Note the translucent wing panels, with light visible throughout the primaries.  (September)
Raptor/Buteo Identification: Broad-winged Hawk
A hatch-year/juvenile Broad-winged Hawk “feeding on the wing” to consume a captured dragonfly.  (September)

SWAINSON’S HAWK (Buteo swainsoni)

Raptor/Buteo Identification: Swainson's Hawk
An adult Swainson’s Hawk.  (May)  (Vintage 35mm image)

RED-TAILED HAWK (Buteo jamaicensis)

Raptor/Buteo Identification: Red-tailed Hawk
In eastern North America, Red-tailed Hawks in all age classes have a speckled belly band.  Compared between individuals and populations, its density and width will vary.  (April)
Raptor/Buteo Identification: Red-shouldered Hawk vs. Red-tailed Hawk
An adult Red-shouldered Hawk (left) harassing an adult Red-tailed Hawk.  (September)

RED-TAILED HAWK (Buteo jamaicensis) Adult

Raptor/Buteo Identification: Red-tailed Hawk
A second-year/adult Red-tailed Hawk beginning molt of the juvenile primaries.  (June)
Raptor/Buteo Identification: Red-tailed Hawk
A second-year/adult Red-tailed Hawk beginning molt of the juvenile rectrices (tail feathers).  Note the growth of the first red replacement.  (Early July)
Raptor/Buteo Identification: Red-tailed Hawk
A second-year/adult Red-tailed Hawk completing molt.  Note the retained juvenile rectrix (the longer tail feather) and the translucent wing panels, with light showing through the inner primaries.  (October)
Raptor/Buteo Identification: Red-tailed Hawk
An adult Red-tailed Hawk.  At times, intense backlighting can make all flight feathers appear translucent.  (March)
Raptor/Buteo Identification: Red-tailed Hawk
An adult Red-tailed Hawk in annual mid-summer molt.  (Late August)
Raptor/Buteo Identification: Red-tailed Hawk
An adult Red-tailed Hawk nearing completion of annual summer molt.  (September)
Raptor/Buteo Identification: Red-tailed Hawk
An adult Red-tailed Hawk soaring.  The dark patagial bar on the leading edge of the proximal portion of each wing is a key field mark for all age classes.  (October)
Raptor/Buteo Identification: Red-tailed Hawk
An adult Red-tailed Hawk in a glide.  Note the carpal crescents formed by a row of dark primary underwing coverts, another key field mark for “Red-tails” in all age classes.  The dark terminal band along the trailing edge of the remiges is a characteristic only of adult birds.  (November)
Raptor/Buteo Identification: Red-tailed Hawk
An adult Red-tailed Hawk.  (November)
Raptor/Buteo Identification: Red-tailed Hawk
An adult Red-tailed Hawk being harassed by an American Crow.  This bird is an example of the faint banding that can be detected in the rufous tails of some adult birds.  (November)
Raptor/Buteo Identification: Red-tailed Hawk
An adult Red-tailed Hawk.  (November)
Raptor/Buteo Identification: Red-tailed Hawk
An adult Red-tailed Hawk in a glide displaying a dark patagial bar, carpal crescents created by a row of dark primary underwing coverts, and a dark terminal band on the trailing edge of the remiges.  (December)

RED-TAILED HAWK (Buteo jamaicensis) Hatch-Year (Juvenile)

Raptor/Buteo Identification: Red-tailed Hawk
A hatch-year/juvenile Red-tailed Hawk.  Note the dark patagial bar on the leading edge of each wing and the carpal crescents formed by a row of dark primary underwing coverts.  (October)
Raptor/Buteo Identification: Red-tailed Hawk
A hatch-year/juvenile Red-tailed Hawk.  Translucent wing panels, with light showing readily through the inner primaries and not the overlapping outer primaries, are a field mark most readily seen on first-year birds like this.  Compared to older “Red-tails”, first-year birds can appear whitish, a look created by the pale juvenile rectrices (tail feathers) and the absence of the dark terminal band found along the trailing edge of the remiges on adults.  (October)
Raptor/Buteo Identification: Red-tailed Hawk
A hatch-year/juvenile Red-tailed Hawk.  Juvenile rectrices may have a faint rufous tint suggesting adult plumage, but fine banding is always present on the tails of first-year birds.  Molt of the juvenile rectrices typically occurs during the bird’s second summer.  (October)
Raptor/Buteo Identification: Red-tailed Hawk
A hatch-year/juvenile Red-tailed Hawk.  (November)
Raptor/Buteo Identification: Red-tailed Hawk
A hatch-year/juvenile Red-tailed Hawk.  (November)

ROUGH-LEGGED HAWK (Buteo lagopus) Hatch-Year (Juvenile)

Raptor/Buteo Identification: Rough-legged Hawk
A hatch-year/juvenile “light morph” Rough-legged Hawk.  Nearly all of a “Rough-leg’s” primary underwing coverts are black, creating a readily visible dark carpal patch.  (December)

Order-Falconiformes

(Falcons)

 


Family-Falconidae

(Falcons)

Falconidae (Falcons)


AMERICAN KESTREL (Falco sparverius) Male

Raptor/Falcon Identification: American Kestrel
A male American Kestrel.  (January) 
Raptor/Falcon Identification: American Kestrel
A hatch-year/juvenile male American Kestrel.  (August)
Raptor/Falcon Identification: American Kestrel
A hatch-year/juvenile male American Kestrel displaying the “string of pearls”, a row of translucent “windows” along the trailing edge of the wings.  (September)
Raptor/Falcon Identification: American Kestrel
A male American Kestrel.  (September)
Raptor/Falcon Identification: American Kestrel
A photo study of a male American Kestrel in flight.  (September)
Raptor/Falcon Identification: American Kestrel
A male American Kestrel reveals a “string of pearls” along the trailing edge of the wings.  (September)
Raptor/Falcon Identification: American Kestrel
A male American Kestrel stooping on a dragonfly.  (September)

AMERICAN KESTREL (Falco sparverius) Female

Raptor/Falcon Identification: female American Kestrel
A female American Kestrel.  (February)
Raptor/Falcon Identification: American Kestrel
A female American Kestrel.  (August)
Raptor/Falcon Identification: American Kestrel
A female American Kestrel.  (August)
Raptor/Falcon Identification: American Kestrel
A female American Kestrel.  (November)
Raptor/Falcon Identification: American Kestrel
A female American Kestrel.  (December)

MERLIN (Falco columbarius)

Raptor/Falcon Identification: Merlin
The Merlin is a fast, dark falcon that quickly passes lookout stations.  (September)
Raptor/Falcon Identification: Merlin
Silhouette of a Merlin.  (October)
Raptor/Falcon Identification: Merlin
A Merlin darts past a hawk counting station.  (November)

“TAIGA MERLIN” (Falco columbarius columbarius)

Adult Male

Raptor/Falcon Identification: "Taiga Merlin"
A probable adult male “Taiga Merlin”.  (September)

“TAIGA MERLIN” (Falco columbarius columbarius)

Adult Female or Hatch-Year (Juvenile)

Raptor/Falcon Identification: "Taiga Merlin"
A probable adult female “Taiga Merlin”.  (May)
Raptor/Falcon Identification: "Taiga Merlin"
A probable adult female “Taiga Merlin”.  (May)
Raptor/Falcon Identification: "Taiga Merlin"
A probable adult female “Taiga Merlin”.  (September)
Raptor/Falcon Identification: "Taiga Merlin"
A probable hatch-year/juvenile “Taiga Merlin”.  (September)
Raptor/Falcon Identification: "Taiga Merlin"
A probable hatch-year/juvenile “Taiga Merlin” with a dragonfly.  (September)
Raptor/Falcon Identification: "Taiga Merlin"
An adult female or hatch-year/juvenile “Taiga Merlin”.  (November)

PEREGRINE FALCON (Falco peregrinus)

Raptor/Falcon Identification: Peregrine Falcon
Silhouette of a Peregrine Falcon in a glide.  Note the broad pointed wings and tapering tail.  (September)
Raptor/Falcon Identification: Peregrine Falcon
A soaring Peregrine Falcon.  (October)
Raptor/Falcon Identification: Peregrine Falcon
A gliding Peregrine Falcon.  In powered flight, note that the tail appears widest at the base, tapering to its narrowest at the tip.  (October)

PEREGRINE FALCON (Falco peregrinus) Adult

Raptor/Falcon Identification: Peregrine Falcon
An adult Peregrine Falcon.  (November)
Raptor/Falcon Identification: Peregrine Falcon in a stoop.
An adult Peregrine Falcon in a stoop, a maneuver enabling these birds to reach speeds approaching 200 miles per hour, the fastest of any animal on earth.  (November)

PEREGRINE FALCON (Falco peregrinus) Hatch-Year (Juvenile)

Raptor/Falcon Identification: Peregrine Falcon
A hatch-year/juvenile Peregrine Falcon.  (August)
Raptor/Falcon Identification: Peregrine Falcon
A hatch-year/juvenile Peregrine Falcon.  (August)
Raptor/Falcon Identification: Peregrine Falcon
A hatch-year/juvenile Peregrine Falcon.  (September)
Raptor/Falcon Identification: Peregrine Falcon
A hatch-year/juvenile Peregrine Falcon.  (September)
Raptor/Falcon Identification: Peregrine Falcon
A hatch-year/juvenile Peregrine Falcon.  (October)

“TUNDRA PEREGRINE” (Falco peregrinus tundrius)

Raptor/Falcon Identification: "Tundra Peregrine"
A “Tundra Peregrine”.  (October)
Raptor/Falcon Identification: "Tundra Peregrine"
A “Tundra Peregrine”.  (October)

“TUNDRA PEREGRINE” (Falco peregrinus tundrius) Adult

Raptor/Falcon Identification: "Tundra Peregrine"
An adult “Tundra Peregrine”.  (September)

“TUNDRA PEREGRINE” (Falco peregrinus tundrius) Hatch-Year (Juvenile)

Raptor/Falcon Identification: "Tundra Peregrine"
A hatch-year/juvenile “Tundra Peregrine”.  The pale forehead and thin mustache (malar stripe) are key field marks.  (October)
Raptor/Falcon Identification: "Tundra Peregrine"
The same hatch-year/juvenile “Tundra Peregrine” seen in the preceding image.  Note how the white superciliary lines (eyebrows) on this bird extend to the back of the head and down to the nape, a field mark shared with some juvenile “Peale’s Peregrines” (F. p. pealei), a mostly non-migratory subspecies found along Pacific Ocean coastlines from Alaska south to California.  (October)
Raptor/Falcon Identification: "Tundra Peregrine"
A hatch-year/juvenile “Tundra Peregrine” equipped with a tracking transmitter.  (October)
Raptor/Falcon Identification: "Tundra Peregrine"
A hatch-year/juvenile “Tundra Peregrine” equipped with a tracking transmitter.  (October)

GYRFALCON (Falco rusticolus)

Raptor/Falcon Identification: female dark-morph Gyrfalcon, Lancaster County, Pennsylvania
Powerful and robust Gyrfalcons are exceptionally rare visitors anywhere south of Canada.  During the winter of 1981-82, this dark-morph female and a white-morph male wintered in the Lower Susquehanna River Watershed in the vicinity of the D. M. Stoltzfus Quarry near Leola, Lancaster County, Pennsylvania.  A third Gyrfalcon, a gray-morph bird, was seen there on numerous occasions as well.  To the astonishment of birders throughout the region, this female and the white-morph male returned to the Stoltzfus Quarry for a second consecutive winter on December 31, 1982.  Soon though, she appeared to be ailing.  A recovery operation was planned and on January 13, 1983, experienced rescuer Thomas Amico rappelled down the walls of the quarry to retrieve the ill bird.  He instead found that she was already deceased.  An examination revealed she died of a duodenal lesion and an abscessed liver caused by an intestinal flatworm.  (Specimen in the Pennsylvania Game Commission collection at the Middle Creek Wildlife Management Area Visitor’s Center)

The perceived visual appearance of raptors in flight can be altered significantly by many conditions including observation angle, distance, lighting, prevailing weather, and a bird’s behavior and flight posture.  Furthermore, some birds do look different than “normal”.  In addition to the variation among individuals regularly occurring in a region, strays from more distant populations possessing unfamiliar traits may wander into an observer’s area from time to time and provide an experience that’s somewhat confounding.  Familiarity with molt cycles and the resulting seasonal changes in plumage can be an asset for identifying and determining the age of a diurnal raptor.  But these changes are not set in stone.  The timing of feather molt can be impacted by genetic variation, nutrition, stress, breeding/nesting activity, and other factors.  Therefore, the information found on this page should be considered as a photographic reference and general overview of field marks presented to familiarize the observer with the basics of identifying and possibly determining the age of a diurnal raptor.  But keep in mind, you will encounter individuals that don’t quite fit the mold. 

WILL YOU BE ABLE TO ACCURATELY INDENTIFY AND AGE EVERY DIURNAL RAPTOR YOU SEE?

YEAH, WHEN PIGS FLY.

A flying pig head?
Is it a bird?  Is it a plane?  Is it a flying pig?  No, wait, it is a bird.  It’s a migrating Broad-winged Hawk diving into the forest to spend the night.  Identifying diurnal raptors sure can be tricky at times.

 

SOURCES

Amico, Thomas M.  1991.  “Gyrfalcons in Lancaster County”.  A Guide to the Birds of Lancaster County, Pennsylvania.  Lancaster County Bird Club.  pp. 116-119.

Dunn, Pete, David Sibley, and Clay Sutton.  1988.  Hawks in Flight.  Houghton Mifflin Company.  Boston, MA.

Dunn, Pete, and Kevin t. Karlson.  2016.  Birds of Prey: Hawks, Eagles, Falcons, and Vultures of North America.  Houghton Mifflin Harcourt.  New York, NY.

Liguori, Jerry.  2005.  Hawks from Every Angle: How to Identify Raptors in Flight.  Princeton University Press.  Princeton, NJ.

Liguori, Jerry.  2011.  Hawks at a Distance: Identification of Migrant Raptors.  Princeton University Press.  Princeton, NJ.