American crow

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American crow
Corvus-brachyrhynchos-001.jpg
In Bruce Peninsula National Park, Ontario
Status TNC G5.svg
Secure  (NatureServe) [2]
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Passeriformes
Family: Corvidae
Genus: Corvus
Species:
C. brachyrhynchos
Binomial name
Corvus brachyrhynchos
Brehm, 1822
Corvus brachyrhynchos distribution.png
Global range
Pair of crows chasing away a red-tailed hawk from their nest Crows chasing away a dangerous red tailed hawk.jpg
Pair of crows chasing away a red-tailed hawk from their nest

The American crow (Corvus brachyrhynchos) is a large passerine bird species of the family Corvidae. It is a common bird found throughout much of North America. American crows are the New World counterpart to the carrion crow and the hooded crow of Eurasia; they all occupy the same ecological niche. Although the American crow and the hooded crow are very similar in size, structure and behavior, their calls and visual appearance are different.

Contents

From beak to tail, an American crow measures 40–50 cm (16–20 in), almost half of which is tail. Its wingspan is 85–100 cm (33–39 in). Mass varies from about 300 to 600 g (11 to 21 oz), with males tending to be larger than females. Plumage is all black, with iridescent feathers. It looks much like other all-black corvids. They are very intelligent, and adaptable to human environments. The most usual call is CaaW!-CaaW!-CaaW! They can be distinguished from the common raven (C. corax) because American crows are smaller and the beak is slightly less pronounced; from the fish crow (C. ossifragus) because American crows do not hunch and fluff their throat feathers when they call; and from the carrion crow (C. corone) by size, as the carrion crow is larger and of a stockier build.

American crows are common, widespread, and susceptible to the West Nile virus, making them useful as a bioindicator to track the virus's spread. Direct transmission of the virus from crows to humans is impossible.

Taxonomy and systematics

The American crow was described by German ornithologist Christian Ludwig Brehm in 1822. [3] Its scientific name means literally 'short-billed crow', from Ancient Greek βραχυ-brachy- ('short-') and ρυνχοςrhynchos ('billed'). [4]

A 2012 genetic analysis of the genus Corvus by Knud A Jønsson and colleagues using nuclear and mitochondrial DNA calculated that the American crow diverged from a lineage that gave rise to the collared, carrion and hooded crows around 5 million years ago. [5]

"American crow" has been designated the official name by the International Ornithologists' Union (IOC). [6]

Subspecies

Northwestern crow range Corvus caurinus map.jpg
Northwestern crow range

The number of subspecies varies by authority, ranging between three and five. The unclear taxonomy of the northwestern crow, previously its own species, has complicated subspecies determinations. Subspecies differ in bill proportion and form a rough NE–SW clinal in size across North America. Birds are smallest in the far west and on the southern coast. [7] [3]

Description

In Brooklyn, New York American Crow Brooklyn, NY.jpg
In Brooklyn, New York
Calling

The American crow is a large, distinctive bird with iridescent black feathers all over. Its legs, feet and bill are also black. They measure 40–53 cm (16–21 in) in length, of which the tail makes up about 40%. The wing chord is 24.5 to 33 cm (9.6 to 13.0 in), with the wingspan ranging from 85 to 100 cm (33 to 39 in). The bill length can be from 3 to 5.5 cm (1.2 to 2.2 in), varying strongly according to location. The tarsus is 5.5 to 6.5 cm (2.2 to 2.6 in) and the tail is 13.5 to 19 cm (5.3 to 7.5 in). [7] The body mass can vary from 316 to 620 g (11.1 to 21.9 oz). Males tend to be larger than females. [14] [15] The most usual call is a loud, short, and rapid caaw-caaw-caaw. Usually the birds thrust their heads up and down as they utter this call. American crows can also produce a wide variety of sounds and sometimes mimic noises made by other animals, including other birds, such as barred owls. [16]

Visual differentiation from the fish crow (C. ossifragus) 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 fish crow's 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. [17]

If seen flying at a distance from where size estimates are unreliable, the distinctly larger common ravens (C. corax) can be distinguished by their almost lozenge-shaped tail and their larger-looking heads. They also fluff their throat feathers when calling – like fish crows, only more so. Ravens also soar for extended periods, unlike crows, which rarely fly more than a few seconds without flapping their wings. [18] [19]

Crows have been noted to be intelligent. They have the same brain-weight-to-body ratio as humans. This has led to some studies that have identified that crows are self-aware and that young crows take time to learn from tolerant parents. While a human has a neocortex, the crow has a different area in their brain that is equally complex. [20] [21]

The average lifespan of the American crow in the wild is 7–8 years. Captive birds are known to have lived up to 30 years. [22]

Distribution and habitat

The skull of an American crow American Crow (Corvus brachyrhynchos) skull at the Royal Veterinary College anatomy museum.JPG
The skull of an American crow

The range of the American crow now extends from the Pacific Ocean to the Atlantic Ocean in Canada, on the French islands of Saint-Pierre and Miquelon, south through the United States, and into northern Mexico. [1] The increase in trees throughout the Great Plains during the past century due to fire suppression and tree planting facilitated range expansions of the American crow [23] as well as range expansions of many other species of birds. [24] [25] [26] Virtually all types of country from wilderness, farmland, parks, open woodland to towns and major cities are inhabited; it is absent only from tundra habitat, where it is replaced by the common raven. This crow is a permanent resident in most of the US, but most Canadian birds migrate some distances southward in winter. Outside of the nesting season these birds often gather in large (thousands or even millions [27] ) communal roosts at night. [28]

The American crow was recorded in Bermuda from 1876 onwards. [29]

Behavior and ecology

Skeleton (Museum of Osteology) American Crow skeleton.jpg
Skeleton (Museum of Osteology)

Studying the behavior of American crows is laborious due to the difficulty in catching them to band them, let alone catching them again. Thus much of their behavior, including daily routine, migration, molting, survivorship, age of first breeding, nestling development, and the nature of nesting helpers, remains poorly studied. [3]

Diet

The American crow is omnivorous. [30] It will feed on invertebrates of all types, carrion, scraps of human food, fruits, [31] nuts such as walnuts and almonds, seeds, eggs and nestlings, stranded fish on the shore and various grains. American crows are active hunters and will prey on mice, young rabbits, [31] frogs, and other small animals. In the winter and autumn, the diet of American crows is more dependent on nuts and acorns. Occasionally, they will visit bird feeders. [32] The American crow is one of only a few species of bird that has been observed modifying and using tools to obtain food. [33]

Like most crows, they will scavenge at landfills, scattering garbage in the process. Where available, corn, wheat and other crops are a favorite food. These habits have historically caused the American crow to be considered a nuisance. However, it is suspected that the harm to crops is offset by the service the American crow provides by eating insect pests. [32]

A fledgling, of the Northwestern subtype Corvus caurinus - June 2007.jpg
A fledgling, of the Northwestern subtype

Reproduction

Egg, in the collection of the Children's Museum of Indianapolis The Childrens Museum of Indianapolis - American crow egg.jpg
Egg, in the collection of the Children's Museum of Indianapolis

American crows are socially monogamous cooperative breeding birds. Mated pairs form large families of up to 15 individuals from several breeding seasons that remain together for many years. [34] Offspring from a previous nesting season will usually remain with the family to assist in rearing new nestlings. American crows do not reach breeding age for at least two years. [35] Most do not leave the nest to breed for four to five years. [34]

The nesting season starts early, with some birds incubating eggs by early April. [36] American crows build bulky stick nests, nearly always in trees but sometimes also in large bushes and, very rarely, on the ground. They will nest in a wide variety of trees, including large conifers, although oaks are most often used. Three to six eggs are laid and incubated for 18 days. The young are usually fledged by about 36 days after hatching. Predation primarily occurs at the nest site and eggs and nestlings are frequently eaten by snakes, raccoons, ravens and domestic cats. Adults are less frequently predated, but face potential attack from great horned owls, red-tailed hawks, peregrine falcons and eagles. They may be attacked by predators such as coyotes or bobcats at carrion when incautious, although this is even rarer. [32] [37]

Leucistic crow feeding its offspring American Crow imported from iNaturalist photo 250510645 on 5 December 2024.jpg
Leucistic crow feeding its offspring

Although matings between relatives can cause inbreeding depression, that is, negative effects on offspring fitness, a number of species never-the-less prefer inbreeding. [38] The American crow experiences inbreeding depression (as measured by fledgling survival) but still prefers inbreeding. [38]

West Nile virus

American crows succumb easily to West Nile virus infection. This was originally a mosquito-borne African virus causing encephalitis in humans and livestock since about 1000 AD, and was accidentally introduced to North America in 1999, apparently by an infected air traveller who got bitten by a mosquito after arrival. It is estimated that the American crow population has dropped by up to 45% since 1999. [39] Despite this decline, the crow is considered a species of least concern. [40] The disease runs most rampant in the subtropical conditions which encourage reproduction of its mosquito vectors among which Culex tarsalis is most significant. Mortality rates appear to be higher than those in other birds, causing local population losses of up to 72% in a single season. [35] [41] Because of this, American crows are a sentinel species indicating the presence of West Nile virus in an area. Crows cannot transmit the virus to humans directly. [22]

Intelligence

American crows, like other corvids, are highly cunning and inquisitive. They are able to steal food from other species, often in creative ways. One example shows a group of crows stealing a fish from a Northern river otter: one bird pecked the otter's tail to distract it while other birds swooped in and stole the fish. [3] They are able to use and modify tools. [42]

Relationship with humans

Crows are used as a motif in some human cultures, often associated with death, thieves, graveyards, bad luck, and other negative connotations. [43]

Conversely, they are seen by some neo-pagan and indigenous cultures as signs of good luck, or even signs of certain gods, such as Apollo, Odin, and others. [44]

Status and management

Brooklyn Museum - American crow - John J. Audubon Brooklyn Museum - American Crow - John J. Audubon.jpg
Brooklyn Museum – American crow – John J. Audubon

The intelligence and adaptability of the American crow has insulated it from threats, and it is instead considered an agricultural pest. [3] In 2012, BirdLife International estimated the American crow population to be around 31 million. The large population and vast range result in the least concern status for the American crow, meaning that the species is not threatened with extinction. [1]

Crows have been killed in large numbers by humans, both for recreation and as part of organized campaigns of extermination. [45] In Canada, American crows have no protections, aside from Quebec, which bans their hunting during the nesting season. [3] Laws on their hunting vary throughout the United States. New Jersey allows for a limited hunting season, unless they are agricultural pests, in which case they may be killed. Oklahoma allows hunting even during the nesting season. In the first half of the 20th century, state-sponsored campaigns dynamited roosting areas, taking large numbers of crows. A campaign in Oklahoma from 1934 to 1945 dynamited 3.8 million birds. The effect on populations was negligible and damage to agricultural crops did not decrease, and thus the campaign was halted due to its ineffectiveness. In a study taking data from 1917 to 1999, intentional killings were the overwhelming cause of death for crows, accounting for 68% of all recovered bird bands. [3]

Non-deadly methods of managing crows are varied but usually limited in their effectiveness. High value crops may be netted, but this is cost prohibitive for most other crops. Frightening may be used to disperse crows, including loud noises from guns, fake hawks flown from balloons, fake owls that move with the wind, strips of reflective tape on fences, or recordings of crow distress calls. Poisoned baits are of limited effectiveness, as only the most toxic baits work, and those are generally unacceptable for use. Crows quickly learn to avoid the less-toxic baits, as the baits make crows sick. The actual effect of crows on agriculture has been poorly studied. [3] There is some suggestion that they may be a benefit to farmers, by eating insect pests and chasing off livestock predators like hawks. [43]

Related Research Articles

<span class="mw-page-title-main">Corvidae</span> Family of perching birds

Corvidae is a cosmopolitan family of oscine passerine birds that contains the crows, ravens, rooks, magpies, jackdaws, jays, treepies, choughs, and nutcrackers. In colloquial English, they are known as the crow family or corvids. Currently, 139 species are included in this family. The genus Corvus containing 50 species makes up over a third of the entire family. Corvids (ravens) are the largest passerines.

<span class="mw-page-title-main">Carrion crow</span> Species of bird

The carrion crow is a passerine bird of the family Corvidae, native to western Europe and the eastern Palearctic.

<span class="mw-page-title-main">Hooded crow</span> Species of bird

The hooded crow, also called the scald-crow or hoodie, is a Eurasian bird species in the genus Corvus. Widely distributed, it is found across Northern, Eastern, and Southeastern Europe, as well as parts of the Middle East. It is an ashy grey bird with black head, throat, wings, tail, and thigh feathers, as well as a black bill, eyes, and feet. Like other corvids, it is an omnivorous and opportunistic forager and feeder.

<span class="mw-page-title-main">Great blue heron</span> Species of bird

The great blue heron is a large wading bird in the heron family Ardeidae, common near the shores of open water and in wetlands over most of North and Central America, as well as far northwestern South America, the Caribbean and the Galápagos Islands. It is occasionally found in the Azores and is a rare vagrant to Europe. An all-white population found in south Florida and the Florida Keys is known as the great white heron. Debate exists about whether these white birds are a color morph of the great blue heron, a subspecies of it, or an entirely separate species.

<span class="mw-page-title-main">Australian raven</span> Passerine bird native to Australia

The Australian raven is a passerine corvid bird native to Australia. Measuring 46–53 centimetres (18–21 in) in length, it has an all-black plumage, beak and mouth, as well as strong, greyish-black legs and feet. The upperparts of its body are glossy, with a purple-blue, greenish sheen; its black feathers have grey bases. The Australian raven is distinguished from the Australian crow, and other related corvids, by its long chest feathers, or throat hackles, which are prominent in mature birds. Older individuals and subadults have white irises, while the younger birds' eyes display blue inner rims; hatchlings and young birds have brown, dark irises until about fifteen months of age, at which point their irises become hazel-coloured, with an inner blue rim around each pupil, this lasting until they are roughly 2.5 to 3 years of age. Nicholas Aylward Vigors and Thomas Horsfield described the Australian raven in 1827, its species name coronoides highlighting its similarity with the carrion crow. Two subspecies are recognised, which differ slightly in their vocalisations, and are quite divergent, genetically.

<span class="mw-page-title-main">Torresian crow</span> Species of bird

The Torresian crow, also called the Australian crow or Papuan crow, is a passerine bird in the crow family native to the north and west of Australia and nearby islands in Indonesia and Papua New Guinea. The species has a black plumage, beak and mouth with white irises. The base of the feathers on the head and neck are white. The Torresian crow is slightly larger with a more robust bill than the morphologically similar little crow.

<span class="mw-page-title-main">Forest raven</span> Australian native bird

The forest raven, also commonly known as the Tasmanian raven, is a passerine bird in the family Corvidae native to Tasmania and parts of southern Victoria, such as Wilsons Promontory and Portland. Populations are also found in parts of New South Wales, including Dorrigo and Armidale. Measuring 50–53 cm (20–21 in) in length, it has all-black plumage, beak and legs. As with the other two species of raven in Australia, its black feathers have grey bases. Adults have white irises; younger birds have dark brown and then hazel irises with an inner blue rim. New South Wales populations are recognised as a separate subspecies C. tasmanicus boreus, but appear to be nested within the Tasmanian subspecies genetically.

<span class="mw-page-title-main">Pied crow</span> Species of bird

The pied crow is a widely distributed African bird species in the crow genus of the family Corvidae.

<span class="mw-page-title-main">Collared crow</span> Species of bird

The collared crow, also known as the ring-necked crow or white-collared crow, is a member of the family Corvidae native to China and north of Vietnam.

<span class="mw-page-title-main">Fish crow</span> Species of bird

The fish crow is a species of crow associated with wetland habitats in the eastern and southeastern United States.

<span class="mw-page-title-main">Fan-tailed raven</span> Species of bird

The fan-tailed raven is a passerine bird of the crow family native to Eastern Africa and the Arabian Peninsula.

<span class="mw-page-title-main">Brown-necked raven</span> Species of bird

The brown-necked raven is a larger bird than the carrion crow though not as large as the common raven. It has similar proportions to the common raven but the bill is not so large or deep and the wings tend to be a little more pointed in profile. The head and throat are a distinct brownish-black giving the bird its English name, while the rest of the plumage is black glossed with purple, blue or purplish-blue. Like the common raven, thick-billed raven and white-necked raven, it is one of the larger raven species. The feathers of this species often fade quite quickly to a brownish black and the bird can look distinctly brown by the time it moults. The feet, legs and bill are black. The dwarf raven was formerly considered a subspecies but this bird now appears to be closer to the pied crow than this species.

<span class="mw-page-title-main">Large-billed crow</span> Species of bird

The large-billed crow, formerly referred to widely as the jungle crow, is a widespread Asian species of crow. It is very adaptable and is able to survive on a wide range of food sources, making it capable of colonizing new areas, due to which it is often considered a nuisance, especially on islands. It has a large bill, which is the source of its scientific name macrorhynchos and it is sometimes known by the common name thick-billed crow. It can also be mistaken for a common raven. The eastern jungle crow and Indian jungle crow were once considered conspecific and together called the jungle crow.

<span class="mw-page-title-main">Rough-legged buzzard</span> Species of bird

The rough-legged buzzard (Europe) or rough-legged hawk is a medium-large bird of prey. It is found in arctic and subarctic regions of North America, Europe, and Asia during the breeding season, and migrates south for the winter. Historically, it was also known as "rough-legged falcon" in such works as John James Audubon's The Birds of America.

<span class="mw-page-title-main">Common raven</span> Large, black, passerine bird of the Northern Hemisphere

The common raven or northern raven is a large all-black passerine bird. It is the most widely distributed of all corvids, found across the Northern Hemisphere. There are 11 accepted subspecies with little variation in appearance, although recent research has demonstrated significant genetic differences among populations from various regions. It is one of the two largest corvids, alongside the thick-billed raven, and is the heaviest passerine bird; at maturity, the common raven averages 63 centimetres in length and 1.47 kilograms in weight, though up to 2 kg (4.4 lb) in the heaviest individuals. Although their typical lifespan is considerably shorter, common ravens can live more than 23 years in the wild. Young birds may travel in flocks but later mate for life, with each mated pair defending a territory.

<span class="mw-page-title-main">White-necked crow</span> Species of crow endemic to Hispaniola

The white-necked crow is the largest of the four Caribbean corvids. It is endemic to the island of Hispaniola ; it was formerly also extant on Puerto Rico and Saint Croix in the United States Virgin Islands, but has been extirpated from both islands due to considerable forest clearance and hunting for meat.

<span class="mw-page-title-main">Crow</span> Index of animals with the same common name

A crow is a bird of the genus Corvus, or more broadly, a synonym for all of Corvus. The word "crow" is used as part of the common name of many species. The related term "raven" is not linked scientifically to any certain trait but is rather a general grouping for larger-sized species of Corvus.

<i>Corvus</i> Genus of birds including crows, ravens and rooks

Corvus is a widely distributed genus of passerine birds ranging from medium-sized to large-sized in the family Corvidae. It includes species commonly known as crows, ravens, and rooks. The species commonly encountered in Europe are the carrion crow, hooded crow, common raven, and rook; those discovered later were named "crow" or "raven" chiefly on the basis of their size, crows generally being smaller. The genus name is Latin for "raven".

<span class="mw-page-title-main">Chihuahuan raven</span> Species of bird

The Chihuahuan raven is a species of crow in the family Corvidae that is native to the United States and Mexico.

References

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  2. ↑ "Corvus brachyrhynchos". NatureServe Explorer. Retrieved 18 July 2024.
  3. 1 2 3 4 5 6 7 8 Verbeek, N. A.; Caffrey, Carolee (August 2021). Poole, A. F.; Gill, F. B. (eds.). "American Crow (Corvus brachyrhynchos) version 1.1" . Birds of the World. Cornell Lab of Ornithology. doi:10.2173/bow.amecro.01.1. S2CID   241865621.
  4. ↑ Liddell, Henry George; Scott, Robert; Stuart-Jones, Henry and McKenzie, Roderick: (1980): A Greek-English Lexicon (abridged ed.). Oxford University Press, Oxford, UK. ISBN   0-19-910207-4.
  5. ↑ Jønsson, Knud A.; Fabre, Pierre-Henri; Irestedt, Martin (2012). "Brains, tools, innovation and biogeography in crows and ravens". BMC Evolutionary Biology. 12 (1): 72. Bibcode:2012BMCEE..12...72J. doi: 10.1186/1471-2148-12-72 . PMC   3480872 . PMID   22642364.
  6. ↑ Gill, Frank; Donsker, David, eds. (2021). "Crows, mudnesters, melampittas, Ifrit, birds-of-paradise". World Bird List Version 11.2. International Ornithologists' Union. Retrieved 26 October 2021.
  7. 1 2 Madge, Steve & Burn, Hilary (1994): Crows and jays: a guide to the crows, jays and magpies of the world. A&C Black, London. ISBN   0-7136-3999-7.
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  9. ↑ Dick, Gary Owen (2007): American Crow. Whatbird.com – Field Guide to Birds of North America. identify.whatbird.com/obj/103/_/American_Crow.aspx Retrieved 2007-October-18.
  10. ↑ Slager, David L.; Epperly, Kevin L.; Ha, Renee R.; Rohwer, Sievert; Wood, Chris; Hemert, Caroline; Klicka, John (2020). "Cryptic and extensive hybridization between ancient lineages of American crows". Molecular Ecology. 29 (5): 956–969. Bibcode:2020MolEc..29..956S. doi:10.1111/mec.15377. ISSN   0962-1083. PMID   32034818. S2CID   211064373.
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  15. ↑ American Crow, Life History, All About Birds – Cornell Lab of Ornithology. Allaboutbirds.org. Retrieved on 2013-03-06.
  16. ↑ Lawrence Kilham (1990). The American Crow and the Common Raven. Texas A&M University Press. pp. 62–. ISBN   978-0-89096-466-8.
  17. ↑ McGowan, Kevin (April 6, 2005). "How do you tell a Fish Crow Corvus ossifragus from an American Crow Corvus brachyrhynchos?". cornell.edu. Retrieved June 2, 2023.
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  19. ↑ Mayntz, Melissa (April 13, 2021). "Raven or Crow: Learn to Identify Both". The Spruce. Retrieved June 2, 2023.
  20. ↑ Amanda Heidt. "Like humans, these big-brained birds may owe their smarts to long childhoods".
  21. ↑ Chris Baraniuk. "Crows have long been considered cunning. But their intelligence may be far more advanced than we ever thought possible".
  22. 1 2 Connecticut Department of Environmental Protection (2001): American Crow Fact Sheet Archived November 5, 2006, at the Wayback Machine . Version of 2001. Retrieved 2006-October-25.
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  29. ↑ Long, John L. (1981). Introduced Birds of the World: The worldwide history, distribution and influence of birds introduced to new environments. Terrey Hills, Sydney: Reed. p. 354. ISBN   0-589-50260-3.
  30. ↑ "American Crow | Audubon Field Guide". www.audubon.org. Retrieved 2024-04-20.
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  32. 1 2 3 C. Parr (2005). "Corvus brachyrhynchos". Animal Diversity Web. Retrieved 13 September 2015.
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  34. 1 2 Roger Segelken: Tree-climbing researcher knows exactly how far the crow flies Archived September 16, 2006, at the Wayback Machine Cornell Chronicle. Retrieved 2006-October-25,
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  37. ↑ Johnson, Ron American Crows Archived 2017-07-16 at the Wayback Machine . Internet Center for Wildlife Damage Management
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  39. ↑ LaDeau, Shannon L.; Kilpatrick, A. Marm; Marra, Peter P. (2007). "West Nile virus emergence and large-scale declines of North American bird populations". Nature. 447 (7145): 710–713. Bibcode:2007Natur.447..710L. doi:10.1038/nature05829. PMID   17507930. S2CID   4337661.
  40. ↑ Deen, David (December 12, 2012). "The crow – a sociable bird with a long memory". The Chronicle. Barton, Vermont. p. 34.
  41. ↑ Caffrey, Carolee; Smith, Shauna C.R.; Weston, Tiffany J. (2005). "West Nile Virus Devastates an American Crow Population". Condor . 107 (1): 128–132. doi: 10.1650/7646 . S2CID   85419982.
  42. ↑ Caffrey, Carolee (June 2000). "Tool Modification and Use by an American Crow". The Wilson Bulletin. 112 (2): 283–284. doi:10.1676/0043-5643(2000)112[0283:TMAUBA]2.0.CO;2. ISSN   0043-5643. S2CID   86124230.
  43. 1 2 Sullivan, Emily. "The Glorious American Crow - Romanticism at SU". Archived from the original on 2020-09-28. Retrieved 2021-10-23.
  44. ↑ "Crow Symbolism & Meaning (+Totem, Spirit & Omens)". CBS 19 News. Retrieved 26 February 2023.
  45. ↑ Campbell, Robert Wayne & Canadian Wildlife Service (1997). "American Crow". The Birds of British Columbia: Passerines : flycatchers through vireos. UBC Press. p. 227. ISBN   978-0-7748-0572-8.

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