Fish Crow
Encyclopedia
The Fish Crow is a species of crow
Crow
Crows form the genus Corvus in the family Corvidae. Ranging in size from the relatively small pigeon-size jackdaws to the Common Raven of the Holarctic region and Thick-billed Raven of the highlands of Ethiopia, the 40 or so members of this genus occur on all temperate continents and several...

 that is associated with wetland habitats in the eastern and southeastern United States.

Taxonomy

The Fish Crow was first described by Alexander Wilson
Alexander Wilson
Alexander Wilson was a Scottish-American poet, ornithologist, naturalist, and illustrator.Wilson was born in Paisley, Scotland, the son of an illiterate distiller. In 1779 he was apprenticed as a weaver. His main interest at this time was in writing poetry...

 in 1812. The latest genetic testing now seems to indicate that this species is close to the Sinaloan Crow
Sinaloan Crow
The Sinaloa Crow is a crow native to western Mexico. Visually, it is nearly identical to and the same length as the Tamaulipas Crow . It has the same purple-glossed, silky, black plumage with a black bill, legs, and feet...

 (Corvus sinaloae) and the Tamaulipas Crow
Tamaulipas Crow
The Tamaulipas Crow a crow found in northeastern Mexico and some of southern Texas.- Description :It is a relatively small and sleek looking crow, in length. It has very glossy dark, bluish plumage, which appears soft and silky. The bill is quite slender and black, as are the legs and feet...

 (Corvus imparatus), and not as close to the American Crow
American Crow
The American Crow is a large passerine bird species of the family Corvidae. It is a common bird found throughout much of North America...

 (Corvus brachyrhynchos) as outward signs would suggest.

Description

The Fish Crow is superficially similar to the American Crow
American Crow
The American Crow is a large passerine bird species of the family Corvidae. It is a common bird found throughout much of North America...

 but is smaller (36–41 cm in length) and has a more silky smooth plumage by comparison. The upperparts have a blue or blue-green sheen, while the underparts have a more greenish tint to the black. The eyes are dark brown. The differences are often only really apparent between the two species when side by side or, when heard calling. The bill is usually somewhat slimmer than the American Crow, but is only readily distinguishable if both species are seen together.

Visual differentiation from the American Crow is extremely difficult and often inaccurate. Nonetheless, differences apart from size do exist. Fish crows tend to have more slender bills and feet. There may also be a small sharp hook at the end of the upper bill. Fish crows also appear as if they have shorter legs when walking. More dramatically, when calling, fish crows tend to hunch and fluff their throat feathers.

The voice is the most outwardly differing characteristic for this species and other American crow species. The call of the Fish Crow has been described as a nasal "ark-ark-ark" or a begging "waw-waw". Birders often distinguish the two species (in areas where their range overlaps) with the mnemonic aid "Just ask him if he is an American Crow. If he says "no", he is a Fish Crow." referring to the fact that the most common call of the American Crow is a distinct "caw caw", while that of the Fish Crow is a nasal "nyuh unh".

Distribution and habitat

This species occurs on the eastern seaboard of the United States from the state of Rhode Island
Rhode Island
The state of Rhode Island and Providence Plantations, more commonly referred to as Rhode Island , is a state in the New England region of the United States. It is the smallest U.S. state by area...

 south to Key West
Key West
Key West is an island in the Straits of Florida on the North American continent at the southernmost tip of the Florida Keys. Key West is home to the southernmost point in the Continental United States; the island is about from Cuba....

, and west along the northern coastline of the Gulf of Mexico
Gulf of Mexico
The Gulf of Mexico is a partially landlocked ocean basin largely surrounded by the North American continent and the island of Cuba. It is bounded on the northeast, north and northwest by the Gulf Coast of the United States, on the southwest and south by Mexico, and on the southeast by Cuba. In...

 and follows many river systems inland for quite some distance. Coastal marshes and beaches are frequented, also rivers, inland lakes and marshes, river banks, and the land immediately surrounding all.

Diet

Food is taken mainly from the ground and even in shallow water where the bird will hover and pluck food items out of the water with its feet. Small crustacean
Crustacean
Crustaceans form a very large group of arthropods, usually treated as a subphylum, which includes such familiar animals as crabs, lobsters, crayfish, shrimp, krill and barnacles. The 50,000 described species range in size from Stygotantulus stocki at , to the Japanese spider crab with a leg span...

s such as crab
Crab
True crabs are decapod crustaceans of the infraorder Brachyura, which typically have a very short projecting "tail" , or where the reduced abdomen is entirely hidden under the thorax...

s, shrimp
Shrimp
Shrimp are swimming, decapod crustaceans classified in the infraorder Caridea, found widely around the world in both fresh and salt water. Adult shrimp are filter feeding benthic animals living close to the bottom. They can live in schools and can swim rapidly backwards. Shrimp are an important...

s, other invertebrates, stranded fish and live fish if the situation favors their capture, eggs and nestlings, small reptiles and fruits of many trees, peanuts and grains, human scraps where available.

Breeding

The nest is usually built high in a tree and is often accompanied in nearby trees with other nests of the same species forming small, loose colonies. There are usually 4-5 eggs laid. Pale blue-green in colour, they bear blotches of olive-brown.

Conservation

This species appears to be somewhat more resistant to West Nile Virus
West Nile virus
West Nile virus is a virus of the family Flaviviridae. Part of the Japanese encephalitis antigenic complex of viruses, it is found in both tropical and temperate regions. It mainly infects birds, but is known to infect humans, horses, dogs, cats, bats, chipmunks, skunks, squirrels, domestic...

than the American crow. Survival rates of up to 45% have been reported for fish crows, compared with near zero for the American species.

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