1. What's in a name?
2. What does it look like?
3. What does it sound like?
4. How does it behave?
5. Where does it live?
6. Cool Facts
   

WHAT'S IN A NAME?

Common name: Northwestern crow

Scientific name: Corvus caurnis

Spanish names: Cuervo Noroccidental

French names: Corneille d'Alaska

"Family Tree" (Taxonomy)

Order: Passeriformes

Family: Corvidae

WHAT DOES IT LOOK LIKE?

Description:

• Black with bluish violet iridescence on head, neck, wings, tail and back
  
• Stout, glossy black bill
  
• Nares cvered with stiff, bristle-like feathers
  
• Fuscous eyes
  
• Sturdy black legs, large-scaled in front and smooth behind
  
• Tails end slightly rounded
• Sexes alike; males are slightly larger than females
• Immatures (3-15 months old) are black, with less iridescence than in adults
  

Size: Small corvid

Similar species: The Northwestern Crow is distinguished from American Crows by its smaller size, smaller feet, faster wing-beat and lower-pitched voice. A small crow seen incoastal Oregon is not necessarily a Northwestern Crow; it is more likely to be a small subspecies of American Crow.

The Northwestern Crow is distinguished from the Common Raven, whose range also overlaps, by its much smaller size, less powerful bill, squarish (instead of wedge-shaped) tail, and absence of shaggy throat feathers. Fish Crows, which do not overlap with the Northwestern Crow, are smaller, lighter, with a smaller bill.

WHAT DOES IT SOUNDS LIKE?

To play this sound, you will need to have RealPlayer installed. To get RealPlayer, click here. Sounds are provided by the Macaulay Library of Natural Sounds.

HOW DOES IT BEHAVE?

What does it eat? Northwestern Crows are omnivorous, meaning their diet is a mix of vegetation and animal life. They eat terrestrial and marine invertebrates, fishes stranded in tidal pools, snakes, amphibians, small birds and mammals, bird eggs, nestlings and fledglings, fruit, seeds, human refuse, and carrion.

Where does it eat? The Northwestern Crow is an opportunistic eater. It forages alone or in groups throughout the year. It obtains most of its food while on the ground walking. Rarely, Northwestern Crows "fly-catch." They're observant, and will spot prey on the ground from an elevated perch. They carry food in a pouch at the base of the throat, transporting large items in the bill or to the feet in flight.

Who eats it? Peregrine falcons take adult crows in some seabird colonies. Goshawks are reported to live mostly on Northwestern Crows. Also, predation by Cooper's Hawk, the Bald Eagle, owls and domestic cats has been observed.

Nesting: Northwestern Crows lay 3 to 6 eggs (pale bluish-green, olive green, pearly gray-green, blue gray, or pale blue, in some cases largely obscured by blotches and spots of darker colors). A pair inspects several potential nest sites together before choosing the final site. It's likely that the female ultimately chooses the spot, as she places most of the nesting material. Nests are located in trees, shrubs and blackberry tangles, well within canopy. Ground nests are placed under trees and shrubs, often near the trunk or against cliffs, in tall grass, and underneath leaning, fallen tree trunks. The nest bottom and sides consist of branches mostly broken from nearby trees and shrubs, a few obtained on the ground along the tide line. The base of the nest cup consists of grass, moss with adherent soil, and leaf duff. Cedar bark, stripped from driftwood logs on beaches, almost always forms the uppermost layer, directly below the eggs.

WHERE DOES IT LIVE?

Range: Northwestern Crows live on the Pacific coast from southern Alaska to the Puget Sound. They are nonmigratory, and move locally within the breeding range. Winter ranges are more or less identical to breeding ranges, and they withdraw from small coastal islands to join winter flocks around towns and along beaches.

Habitat: The Northwestern Crow nests near intertidal zones, where it forages. Coastal bays, river deltas, and intertidal shores, generally near forested shores, seabird colonies and refuse dumps, beaches and reefs, and along tidal pools are also supportive areas. They may also be found in coastal villages, towns, cities and campgrounds, and on farmland and near cleared land.

COOL FACTS

• The Northwestern Crow may be only a subspecies of the American Crow. The two are extremely similar, differing in just size and voice. In the Puget Sound area, a number of intermediate crows can be found, and just what species is the common one there is difficult to determine.
• In play, the Northwestern crow repeatedly flies high into the air to drop (from either its bill or feet) and catch (with its bill) small objects, such as twigs, following with diving flights.
• Northwestern Crows will take hard food items such as clams and crabs and drop them from mid-air to break them open, and will also drop large snakes to stun or kill them.
• Northwestern Crows store food in caches in the ground (especially during low tide) then retrieves it (usually within 24 hours). 
• The Northwestern Crow nests in iisolated pairs or in loose clusteres in exclusive territories, often near intertidal flats, where it procures much of its food in communal flocks. Some pairs have an immature helper that assists in feeding and defending the nestlings. The species is among the northernmost known to have helpers at the nest.
• Northwestern Crows pick food off the surface of the ground or vegetation; it probes its bill into turf and flicks small objects sideways with its bill to expose food. It grasps heavier objects, such as stones, in its bill if possible, and tosses them aside, or puts bill-tip under or against an object to tilt and roll it forward. It's also known to dig in turf, sand, and pebbles to expose food.
• It is just as adapted to digging clams and catching small crabs and fish on beaches as it is to snatching eggs from unwary seabirds, helping itself to unattended picnic baskets and rummaging in garbage cans in urban areas.
• Northwestern Crows choose to store the larger clams that they have dug when compared in size to clams dropped and eaten when found. They memorize cache locations, and recovery success is usually 99 percent. They may have a sense of smell that they can use to detect decaying food.
• Northwestern Crows stand near feeding Bald Eagles, Peregrine Falcons, and Glaucous-winged Gulls, waiting for leftovers.
• The Northwestern Crow drinks fresh water, despite spending so much time along and in salt water. In over 30 years of study, they have never been observed drinking salt water. The male adds fresh water to the food bolus intended for the female by drinking just before feeding her on the nest.
• The Northwestern Crow walks into shallow fresh water to bathe, using conventional stand-and-dip methods. After a prolonged dry period, it bathes by fluttering among wet tree leaves and dries its feathers by vigorously shaking its wings and ruffling body-feathers. On stormy days, it dries its body and wing feathers by facing into the wind and dangling its wings loosely, half open.
• It makes physical contact with others during territorial and feeding interactions, while avoiding physical contact in most other cases with sound and body language. When fights do occur, the birds grapple while laying on their sides, or one bird standing on the belly of the other, and the birds peck at each others' bills.
• All ages roost socially during the nonbreeding season in traditional roosts. Flocks can approach the roost noisilyand gather noisily in trees or buildings near the roost well before sunset. Their repertoire of communicative signals, both visual and auditory, is well developed. Northwestern Crows gather quickly in flocks, in response to alarm calls, to mob predators.
• Northwestern Crows mob perched predators from safe distances while perched higher off the ground than the predator, particularly when nearby. The Mobbing Call quickly draws others to the scene; the resulting noise can be deafening. They also mob gray squirrels, raccoons, river otters, and domestic cats and dogs, as well as people.
  

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Sources used to construct this page:

Verbeek, N.A.M. and C. Caffrey. 1999. Northwestern Crow (Corvus caurinus). In The Birds of North America, No. 407 (A Poole and F. Gill, eds). The Birds of North America, Ince., Philadelphia, PA.