Introducing the fish crow (Corvus ossifragus).
Having just moved to Vero, I had an endearing experience. Relaxing in my pool, a very large black bird — a crow, apparently — flew directly over me and landed on the roof ridge. It looked down at me, feathers ruffling in the breeze. I wasn’t sure what type of crow it was. I decided to test for fish crow, and did my best to mimic its characteristic call, “ah oh,” in my best crow voice. Amazingly, it answered “ah oh” — the real thing, fish crow it was. I called again; it answered again. Back and forth, four times. Then, presumably bored, it left.
When we lived in Virginia, the tall oaks behind our home were visited regularly by scores of noisy American crows. Their call is “caaw caaw caaw.” I love crows, and why not? They are social, intelligent, opportunistic, entertaining, with great physical presence. And traversing fixed ground, they hop!
Correct you are, these are the black birds that appear in our sky in large numbers, gliding and circling for long periods, making all kinds of noise. Alternatively, one or two streak by at low altitude. Very noticeable — purposefully so, I think. Show offs.
Appearance
Plumage is all black, with blue or blue-green sheen. Feet, legs, and bill also black. Dark brown eyes. Average adult weight is roughly 10 ounces, wingspan 11 inches, overall body length 15 inches. Female slightly smaller than male. The upper bill may have a small, sharp hook.
Behavior
Very social. Found in pairs in breeding season, builds nest in small, loose colony. May mix with American crows. Also very intelligent, cunning, inquisitive. Able to steal food from other species, use and modify tools, drops mollusks from height to break shell.
Song
“Ah oh,” also single “cahrrr.” When calling, will hunch and fluff throat feathers.
Distribution and Habitat
Common along the eastern seaboard of U.S. from Rhode Island to Key West, west along the northern coastline of the Gulf of Mexico, follows many rivers inland for considerable distances. Beaches and coastal marshes, tidewater, inland lakes. Increasing range north and inland. Do not migrate in winter.
Feeding
Omnivorous, i.e., obtains nutrients by feeding on both plants and animals. Does most foraging by walking. Broad assortment of preferred items: crabs and shrimps, other invertebrates, stranded fish, eggs and nestlings of birds, small reptiles, turtle eggs, fruits of many trees, berries, seeds, nuts, carrion, garbage.
Nesting
Nest may be high or low in upright fork of trees and shrubs. Built by both sexes. On coast, located in stands of pines and cedars. Shape described as bulky platform of sticks and strips of bark, lined with grass, hair, feathers, paper, pine needles. A new nest is built for each breeding attempt.
Breeding
Four or five eggs are laid, pale blue-green in color with olive-brown blotches. Incubation by female. Both parents bring food to nestlings. Young leave the nest in roughly three to four weeks. Average lifespan seven to eight years in the wild.
Conservation Status
Categorized as “least concern” by the IUCN given large population and vast range. More resistant to West Nile virus than the American crow: estimated survival rate of 45 percent versus near zero for American crow, whose population has declined by almost half since 1999. (Crows cannot transmit the virus to humans directly.
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