Fall Class Hawk Notes

These are the notes taken by Ed Pullen from Ken Brown’s TAS 2010-11-16 Fall Bird Class

Hawks:

Vultures: 
Turkey Vulture:  SBS, though not extensively studied.  Several years ago vultures were reclassified to be closer to storks, but Howell now thinks they will be moved again, though not clear to where.  6-8 years to get to full adult aspect. Fledge in 2-6 months, breed at about 6 years.  This means that they are growing juvenile feathers for a long time and they are strong so they can last a whole year.  IN fall a bird with all nicely grown flight feathers it is a juvenile, because all the other will be molting.  Accelerated step-wise molt. In PB 2 they molt all their flight feathers, and in the spring the molt 1-4 feathers.  So in the second year of life they molt 12-14 flight feathers. After that they molt all the feathers in the fall, i.e. the rest out to P10 and the P1-4 again.   Note the silvery flight feathers.

Osprey:  summer breeders, most leave by Oct.    CBS.  Stepwise molt.  Stepwise molt occurs in large birds that cannot molt all their flight feathers in one year.   Referred to as cycle and wave of flight feathers.  First stepwise molt at 5 months of age is P1-10.  Second wave starts at 15 months.  Third wave starts at 23-32  months P1-7  Then at  36 – 42 months is P8-P1.

White-tailed Kite:  first seen in WA 1975.  CBS.  Off and on since then. Prefer river valleys in SW WA.   Whitish looking, hover hunt, gull-like appearance.  Small bill.  Open pastures, small canyons, small valleys. Perch in trees.  Juveniles are orangish colored.

 Hawks- Eagles- Kites all in the same family, all CBS.  Falcons also CBS.

This means they all have a preformative molt but that this PF molt is usually limited, and at times absent.  In the more northern birds preformative molt is near the nesting grounds.  Some may protract and have this in the spring.  Southerly birds tend to have a more extensive preformative molt.  Examples are Goshawk, very limited and early.  WT Kite more extensive and extended.

The formative molt can be variable.  This means that there can be a big variation in the appearance of the young birds, because some have more preformative molt than others.

Hawks are morphologically, biochemically, and physically quite different from falcons.

Golden Eagle:  stepwise molt  Golden hackles, young birds have white patch on bases of primaries underwing an white at base of the tail underside.  Bulging secondaries, smaller headed less than half the tail length.  Golden hackles on back of the neck at all ages.

Bald Eagle:  stepwise molt.  Start to breed at 4-7 years, can take up to 7 years to have full adult aspect,  Fledge in 1-3 months.  As with most hawks females are larger.  Females often shed their flight feathers earlier, often before nesting, then suspend the molt until off the nest, then resume after off the eggs.  Male who is smaller can wait longer, and start molt after the eggs hatch and the female can start to help with hunting.  In young bald eagles the head size is over half the tail length.  Bald eagles have variable amount of white in the body, Young bald eagles have whitish coverts.  (golden eagle can have some white spots in the covert during molt, but usually not lines like young bald)   Bald Eagles usually hold their wings out straight, but can use a dihedral.  Back of the wing is a fairly straight line, less bulge in the secondaries than the golden eagles.  3-4000 in winter in W WA.  7-800 in summertime.  In E WA on lakes and rivers lots  of bald eagles.  Golden eagles more often in dryer forested areas.  More golden eagles in summer.

Northern Harrier:  Males pale gray, black emarginated feathers.  Females and young much outnumber males.  Course low over ground in marshes, but can soar high too.  Young birds have dark eyes, adults have yellow eyes.  Adult females have streaks below.  Young birds tend to be buffy on the neck and chest, as well as a band on the carpal.

Accipitors:  3 sizes:  SSHA- flicker size, COHA size of a crow, GOHA the size of a RTHA.

Sharp-shinned hawk:  note smaller head so the eye looks more centered,Young has yellow eye, adults have a red eye.  Somewhat squarish tail, sometimes notched.  Outer feathers of the tail nearly as long as the inner tail feathers. Note just a tiny white band on the tip of the tail.  (wider in Cooper’s)  SSHA looks more dirty bellied than COHA.  More coarse streaks, and lesser white, especially near the vent.  Remember the GISS.  3-4 quick choppy strokes and a glide.  VIewed from overhead the wing is pushed forward.

Cooper’s Hawk:  Eye more forward, broader white tipped tail, Adult with nice defined cap, sometimes a peak at the back of a flat head.  Soaring the forward wing is straight off the bird, in flight not as choppy, powerful and in flight looks like the whole wing flaps  If in doubt, and you cannot tell, especially in flight, it’s likely a sharp shinned hawk.  Tend to be more rural.  More Coopers nest here, in winter a lot more SSHA.

Northern Goshawk:  1-3 years to full adult aspect.  Young birds in plumage resemble sharp shinned hawks, more dingy on breast and belly.  Wing pattern is checkerboard look under side.  Wide tubular tail, almost as wide as the body.  Juvenile undertail has wavy underside.  Adults have nice eyeline, yellowish cere, barred below, mostly a bird of the edge habitit, more in E WA.  Pine forest at some elevation.  W WA more deep forest, sometimes at Skagit.

Red-shouldered Hawk:  first seen 1979 at Nisqually. More SW WA.  Pale crescent in the wings.  Smaller bird, small bill, red shoulder, banded tail.  Perch hunters.  Tend to hunt low like an accipitor.  Look in the understory.  Often seen on borders.

Broad-winged Hawk: many more recently.  Very small buteo.  Polymorphic, though light morph much more common.   Fine barring on the tail in young bird.  Whole wing can be bordered in black in the adult.  Perch hunters.  In WA most seen in the first week of Sept.

Swainson’s Hawk:  Summer birds  Note dark primaries light wing linings  Narrow pointed wings. Long distance migrants.  To Argentina.

Red-tailed Hawk:  Dark head, light chest, belly band.  Many morphs, 5-6 subspecies.  Also polymorphic.  So each subspecies has different morphs.  In WA we have 3 morphs in RTHA.  Black morph, Light Morph. Intermediate morph (rufous morph)  Look for the patagium.  This is pretty specific for RTHA.  Wings a bit shorter, often soars, usually takes 3-4 slow flaps and soars again, Tends to sit on the side of a tree, often 2/3 – 3/4 of the way up.  (vs. RLHA often on top of small tree)

Harlan’s Hawk:  (A race of Red-tailed) Dark morph more common.  Dark morph has near white tail,  Juvenile has silvery flight feathers, look for light tail, can be suffused with gray or rust.  Some have very dark body some white streaking on the breast.  (Dark form RT has red tail)  Juvenile difference is a problem.  Juvenile RT has darkish tail with fine banding.  Usually in Harlan’s juvenile the tail has a lighter base.  Underwing coverts in Harlan’s Juvenile tend to be checkered.    Harlan’s white morph look for very white tail.

Ferruginous Hawk:  rare in winter.  Lanky bird, long wings.  Dark morph is unusual.  Has light tail.  Longer wings.  Bright cere, rufous leggings, Note white base of primaries from above, very light from below, rufous “V” of the legs.   Short distance migrants.  Return early.  Mostly found in great plains.

Rough-legged Hawk:  primarily 2 morphs.  Dark and Light.  Young birds very whitish on back.  Usually a wide dark belly band.  Very small bill with bright yellow cere.  Long lanky wing compared to RTHA.  Hover hunt.  Look for black wrist mark.  Females more light headed.  5:1 ratio of light to dark morphs.  Most young and females in WA in winter.  Dark morph female has more white base of the undertail.  Male more banding on the base of the undertail.  Bright yellow legs, feet and bill.  Look for tail to near the tip of the primaries, in RTHA shorter wings.

Falcons:

Merlin:  3 subspecies, Suckleithat we commonly get (black) often lacks the eyebrow.  Taiga- usually an eyebrow, some banding on the tail.   Overall small, near kestrel size, but wings pump like pistons, strong and fast.

American Kestrel:  sexes look different.  Hover hunt, weaker fliers.

Gyrfalcon:  Large, RTHA size, two main morphs, gray and white with variation down to black.  Almost all of ours are gray in WA.  Adults have yellow ceres and dark eyes.  Juveniles tend to be brownish, with a bluish cere.  Slight moustache.  Short wings when sitting, fall well short of the tip of the tail.  Prairie falls 1 “ above the tip of the tail, Peregrine falls about to the tip of the tail.  Powerful flight, hunt by brute force.  Often fly close to the ground and fly down prey.  Comfortable sitting on the ground, sit on a high clump of dirt or mound.

Peregrine Falcon:  3 subspecies, ours are all mixed up now.  Stoop hunt.  Wings fall near the tip of the tail.  Wing tips seem to whip when they fly, making it look like the action is in the tip of the wing.

Prairie Falcon:  brownish bird. Wings fall well short of the tip of the tail.  Black axillars.  Tend to fly looking more mechanical with the whole wing moving.  Surprise hunters, surprise prey.  Not as much stooping.

 

 

 

 

 

Falcons have a different molt pattern.  Molt starts at about P4, moves in and out at the same time, so that P1 and P10 fall at about the same time.  Also starts at S5 and goes both ways.  At the same time S5 is shed the innermost tertial is shed, and moves outward.

 

 

 

Gyrfalcon:  mostly brown immature, and gray adults, White only recorded twice in WA, Adults have yellowish cyr, immature has bluish cyr, only some birds have an eye stripe, Open areas, very fast flyers, tend to fly low to the ground, fast shallow steady wing beat, seems to be centered in the primaries.  Use brute force and surprise to overpower prey, tend to hunt  grouse and partridge in E. WA.

 

Peregrine Falcon:  3 types, Pacific type, prairie type, and tundra type.   In tundra type look for white on forehead and larger white in cheek patch.  Flight is steady and fluid, looks like the whole wing is moving.  Recovered from DDT caused endangerment.  Often moderate height to very high.   Wings go to the tip of the tail