Thursday, May 2, 2024

Raptors Overhead

Birds of prey make a fascinating presence at Halibut Point. If you get a good look ‒ generally at one that's perched ‒ the talons, hooked beak, and penetrating stare tell the story of the raptor's lifestyle and why it's liable to be mobbed by other birds upon discovery. Their raucous harassment may be the first you know of the raptor's presence. 

More often you'll see raptors in the air, where specific identification can be difficult. You might get only a glimpse of a large fast-moving bird zipping by at treetop level. Or you may notice a faraway speck circling in the sky. Right now the raptors migrating past this area give us one of our best chances for an admiring look. There are many plumages, postures, and age-groups to sort through in making a positive raptor identification. Your sighting will fall into one of these groups. 

BUTEOS

Adult Red-tailed Hawk

The Red-tailed Hawk, seen occasionally as a roadside sentinel in a tree or utility pole, is our most common local raptor. Its chunky proportions and relatively short-tail are characteristic features of buteos

Juvenile Red-tailed Hawk

This juvenile has not yet taken on its mature plumage and eponymous tail coloration. It circles over open areas using long rounded wings and widely spread wide tail feathers to support its lofty soaring on the lookout for small mammal prey far below.

Pictured below are two other buteos overflying Halibut Point. In migration they search out thermal updrafts to gain altitude and glide down forward to the next one on their route, occasionally using spare wing beats.

Broad-winged Hawk

Red-shouldered Hawk

Immature Bald Eagle

Based on anatomical proportions and hunting habits Bald Eagles can be thought of as dark-colored oversized buteos. Adults are distinguished by their white heads and tails. In flight eagles hold their wings level and steady unlike vultures, the other large dark birds, that tilt in flight with wings paired conspicuously in a V-shaped dihedron, and are not adapted to the pursuit of live prey. 

ACCIPITERS

Cooper's Hawk

Accipiters chase small birds and mammals through shrubbery and forested areas. Their relatively short wings and long tail give them exceptional maneuverability. In flight they can often be distinguished by a series of short, rapid flaps followed by a glide.

Cooper's Hawk

Cooper's Hawk, the most common local accipiter, is a crow-sized bird with a conspicuously striped tail. The Sharp-shinned Hawk that closely resembles it is the size of a Blue Jay. 

HARRIER

Northern Harrier

Northern Harriers look for prey from stationery perches such as fence posts, or on the wing by circling low over open country, especially marshes. Thus they are infrequently encountered on the moors and woodlands of Halibut Point.  Long tails and pointed wings enable them to pounce quickly on prey during their low altitude sallies. A prominent white patch above the tail and wings held in a dihedral distinguish Harriers from other raptors.

FALCONS

Falcons use their slender, pointed wings to pursue other birds in wide open spaces. They patrol with steady flapping before sudden acceleration when giving chase.

Merlin

The Blue Jay-sized Merlin may also hunt from a stationery perch. It closes on its prey with powerful, piston-like wing beats.

Peregrine Falcon

This Peregrine Falcon found thermals last week to soar almost stationery in the air rising above Halibut Point. Sometimes they ride these updrafts to great heights, tuck in their pointy wings and plunge with terrific speed on unsuspecting victims. 

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Red-tailed Hawk with prey in talons

Raptors in their various sizes, shapes, and skills illustrate the marvel of diverse niche adaptations in the natural world.



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