American crow

{{Short description|Species of passerine bird}} {{Good article}} {{Speciesbox | image = Corvus-brachyrhynchos-001.jpg | image_caption = American crow in Bruce Peninsula National Park, Ontario | image2 = Corvus brachyrhynchos - American Crow - XC115429.ogg | image2_caption = Sound (including rattling) | status = LC | status_system = IUCN3.1 | status_ref = <ref name="iucn">{{cite iucn |author=BirdLife International |date=2018 |title=''Corvus brachyrhynchos'' |volume=2018 |article-number=e.T22705990A131945410 |doi=10.2305/IUCN.UK.2018-2.RLTS.T22705990A131945410.en |access-date=19 November 2021}}</ref> | status2 = G5 | status2_system = TNC | status2_ref = <ref name="NatureServe">{{cite web|title=Corvus brachyrhynchos|url=https://explorer.natureserve.org/Taxon/ELEMENT_GLOBAL.2.1168778/Corvus_brachyrhynchos|website=NatureServe Explorer|access-date=18 July 2024}}</ref> | genus = Corvus | species = brachyrhynchos | authority = Brehm, 1822 | range_map = Corvus brachyrhynchos map.svg | range_map_caption = Range map {{legend|#ff9955|Breeding}}{{legend|#8d5fd3|Year-round}}{{legend|#87aade|Nonbreeding}} }}

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, only absent from the tundra biome. The American crow is the New World counterpart to the carrion crow and the hooded crow of Eurasia, occupying similar ecological niches.

The American crow has all-black plumage, with iridescent feathers. It looks similar to other all-black corvids. It is highly intelligent, similar to other Corvidae, and is adaptable to human environments.

The American crow can be distinguished from the common raven by its smaller size and a slightly less pronounced beak, and from the carrion crow by its size, as the carrion crow is larger and of a stockier build. The American crow can be difficult to distinguish from the fish crow; however, the fish crow tends to fluff its throat feathers when calling. The American crow is an omnivore, feeding on insects, seeds, nuts, and preying on small animals. It also rarely feeds on carrion, leading to associations with death, thieves, and bad luck in some cultures; however, in Native American and some Gaelic cultures, crows are considered good luck due to their intelligence.

The American crow is common, widespread, and susceptible to the West Nile virus, making it a useful bioindicator for tracking the virus's spread. Direct transmission of the virus from crows to humans is impossible. According to BirdLife International, there are 31 million American crows as of 2012.

==Taxonomy and systematics== The American crow was described by German ornithologist Christian Ludwig Brehm in 1822.<ref name="Verbeek-2021" /> Its scientific name means literally 'short-billed crow', from Ancient Greek {{lang|grc|βραχυ-}} {{lang|grc-Latn|brachy-}} ('short-') and {{lang|grc|ρυνχος}} {{lang|grc-Latn|rhynchos}} ('billed').<ref name=Liddell/>

A 2012 genetic analysis of the genus ''Corvus'' calculated that the American crow diverged from a lineage that gave rise to the collared, carrion, and hooded crows around 5 million years ago.<ref name="jonsson 2012">{{cite journal|author1=Jønsson, Knud A. |author2=Fabre, Pierre-Henri |author3=Irestedt, Martin |year=2012|title=Brains, tools, innovation and biogeography in crows and ravens|journal=BMC Evolutionary Biology|volume=12|issue=1 |doi=10.1186/1471-2148-12-72 |page=72 |pmid=22642364 |pmc=3480872 |doi-access=free |bibcode=2012BMCEE..12...72J }}</ref>

"American crow" has been designated the official name by the International Ornithologists' Union (IOU).<ref name="ioclist">{{cite web| editor1-last=Gill | editor1-first=Frank | editor1-link=Frank Gill (ornithologist) | editor2-last=Donsker | editor2-first=David | year=2021 | title= Crows, mudnesters, melampittas, Ifrit, birds-of-paradise | work=World Bird List Version 11.2 | url=https://www.worldbirdnames.org/bow/crows/ | publisher=International Ornithologists' Union | access-date=26 October 2021}}</ref>

===Subspecies=== 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.<ref name="m&b1994" /><ref name="Verbeek-2021">{{Cite journal|last1=Verbeek|first1=N. A.|last2=Caffrey|first2=Carolee|date=August 2021|editor-last=Poole|editor-first=A. F.|editor2-last=Gill|editor2-first=F. B.|title=American Crow (Corvus brachyrhynchos) version 1.1|url=https://birdsoftheworld.org/bow/species/amecro/cur/introduction|journal=Birds of the World|language=en|publisher=Cornell Lab of Ornithology|doi=10.2173/bow.amecro.01.1|s2cid=241865621 |url-access=subscription}}</ref>

* ''C. b. brachyrhynchos'' (Brehm, 1822) – '''eastern crow''': northeastern United States, eastern Canada, and surroundings. The nominate subspecies, and largest.<ref>{{Cite book |last=Brehm |first=L. (Ludwig) |url=http://archive.org/details/beitrgezurvg03breh |title=Beiträge zur Vögelkunde in vollstandigen Beschreibungen mehrerer neu Entdeckter und vieler seltener oder nicht gehörig beobachteter deutscher Vögel |date=1820 |publisher=Neustadt-an-der-Orla |others=University of Illinois Urbana-Champaign}}</ref> * ''C. b. hesperis'' (Ridgway, 1887) – '''western crow''': western North America except the Arctic north, the Pacific Northwest, and the extreme south. Smaller overall with a proportionally more slender bill<ref name="g&g87">Goodwin & Gillmor (1976): p. 87</ref> and low-pitched voice. * ''C. b. caurinus'' (Baird, 1858) ''–'' '''northwestern crow''': of the Pacific temperate rain forests was formerly considered a distinct species as ''C. caurinus'', averaging smaller in size than other American crows with a distinctly hoarser call.<ref name="Dick" /> It forms a hybrid swarm with the American crow (''sensu stricto'') in coastal Washington and British Columbia.<ref name="Pyle, Peter 1997">{{Cite journal|last1=Slager|first1=David L.|last2=Epperly|first2=Kevin L.|last3=Ha|first3=Renee R.|last4=Rohwer|first4=Sievert|last5=Wood|first5=Chris|last6=Hemert|first6=Caroline|last7=Klicka|first7=John|date=2020|title=Cryptic and extensive hybridization between ancient lineages of American crows|url=https://onlinelibrary.wiley.com/doi/10.1111/mec.15377|journal=Molecular Ecology|language=en|volume=29|issue=5|pages=956–969|doi=10.1111/mec.15377|pmid=32034818 |bibcode=2020MolEc..29..956S |s2cid=211064373 |issn=0962-1083|url-access=subscription}}</ref> In 2020, the American Ornithological Society reclassified the Northwestern Crow as conspecific with the American Crow.<ref>{{Cite journal|last1=Chesser|first1=R Terry|last2=Billerman|first2=Shawn M|last3=Burns|first3=Kevin J|last4=Cicero|first4=Carla|last5=Dunn|first5=Jon L|last6=Kratter|first6=Andrew W|last7=Lovette|first7=Irby J|last8=Mason|first8=Nicholas A|last9=Rasmussen|first9=Pamela C|last10=Remsen|first10=J V|last11=Stotz|first11=Douglas F|date=2020-07-24|title=Sixty-first Supplement to the American Ornithological Society's Check-list of North American Birds|journal=The Auk|language=en|volume=137|issue=3|article-number=ukaa030|doi=10.1093/auk/ukaa030|issn=0004-8038|doi-access=free}}</ref> It is now considered a geographic variation within ''C. b. hesperis''.<ref>{{Cite web|title=Corvus brachyrhynchos hesperis (caurinus or occidentalis) (American Crow (caurinus or occidentalis)) – Avibase|url=https://avibase.bsc-eoc.org/species.jsp?lang=EN&avibaseid=2F784967D3BE1046|access-date=2021-10-19|website=avibase.bsc-eoc.org}}</ref> * ''C. b. pascuus'' (Coues, 1899) – '''Florida crow''': Florida. Mid-sized, short-winged, but decidedly long bill and legs.<ref name="g&g87" /> * ''C. b. paulus'' (Howell, 1913) – '''southern crow''': southern United States. Smaller overall, the bill is also small.<ref>Goodwin & Gillmor (1976) p. 88.</ref>

==Description== thumb|In Brooklyn, New York{{Multiple image | image1 = American crow in spring.ogg | image2 = Corvid in tree calling.gk.webm | footer = Calling | direction = vertical }}

The American crow is a large, distinctive bird with iridescent black feathers all over. Its legs, feet, and bill are also black. They measure {{convert|40|–|53|cm|in|abbr=on}} in length, of which the tail makes up about 40%. The wing chord is {{convert|24.5|to|33|cm|in|abbr=on}}, with the wingspan ranging from {{convert|85|to|100|cm|in|abbr=on}}. The bill length can be from {{convert|3|to|5.5|cm|in|abbr=on}}, varying strongly according to location. The tarsus is {{convert|5.5|to|6.5|cm|in|abbr=on}} and the tail is {{convert|13.5|to|19|cm|in|abbr=on}}.<ref name="m&b1994" /> The body mass can vary from {{convert|316|to|620|g|oz|abbr=on}}. Males tend to be larger than females.<ref>Kilham, Lawrence. The American Crow and the Common Raven. p. 52</ref><ref name=":2">{{Cite web|title=American Crow Life History, All About Birds, Cornell Lab of Ornithology|url=https://www.allaboutbirds.org/guide/American_Crow/lifehistory|website=www.allaboutbirds.org|access-date=2025-11-30|language=en}}</ref>

The most usual call is a loud, short, and rapid ''{{not a typo|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.<ref name="Kilham1990">{{cite book|author=Lawrence Kilham|title=The American Crow and the Common Raven|url=https://books.google.com/books?id=GDYXjr2Pk-8C&pg=PA62|year=1990|publisher=Texas A&M University Press|isbn=978-0-89096-466-8|pages=62–}}</ref>

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.<ref>{{Cite web |last=McGowan |first=Kevin |date=April 6, 2005 |title=How do you tell a Fish Crow Corvus ossifragus from an American Crow Corvus brachyrhynchos? |url=https://www.birds.cornell.edu/crows/FishCrow.htm |access-date=June 2, 2023 |website=cornell.edu}}</ref><ref>{{Cite web |title=Fish Crow Similar Species to, All About Birds, Cornell Lab of Ornithology |url=https://www.allaboutbirds.org/guide/Fish_Crow/species-compare/ |access-date=2025-10-28 |website=www.allaboutbirds.org |language=en}}</ref><ref>{{Cite web |date=2016-07-13 |title=Birdist Rule #65: How to Tell the Difference Between Crows {{!}} Audubon |url=https://www.audubon.org/magazine/birdist-rule-65-how-tell-difference-between-crows |access-date=2025-10-28 |website=www.audubon.org |language=en}}</ref>

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.<ref>{{Cite web |date=2012-10-22 |title=How to Tell a Raven From a Crow {{!}} Audubon |url=https://www.audubon.org/magazine/how-tell-raven-crow |access-date=2025-10-28 |website=www.audubon.org |language=en}}</ref><ref>{{Cite web |date=2024-10-22 |title=How to Tell Crows and Ravens Apart by Sight and Sound |url=https://www.allaboutbirds.org/news/similar-species-crows-and-ravens/ |access-date=2025-10-28 |website=All About Birds |language=en-US}}</ref> They also fluff their throat feathers when calling, similarly to fish crows.<ref>{{Cite web |last=Enthusiast |first=The Urban Nature |date=2023-10-28 |title=Tell Crows and Ravens Apart — Corvid Clarity |url=https://urbannature.blog/2023/10/28/telling-crows-and-ravens-apart/ |access-date=2025-10-28 |website=The Urban Nature Enthusiast |language=en-US}}</ref> Ravens also soar for extended periods, unlike crows, which rarely fly more than a few seconds without flapping their wings.<ref>{{Cite web |title=Differences Between an American Crow and a Common Raven (with Map, Pictures, and Sounds) |url=https://avianreport.com/identification-raven-crow/ |access-date=June 2, 2023 |website=Avian Report|date=22 July 2020 }}</ref><ref>{{Cite web |last=Mayntz |first=Melissa |date=April 13, 2021 |title=Raven or Crow: Learn to Identify Both |url=https://www.thespruce.com/american-crow-or-common-raven-386345 |url-status=dead |archive-url=https://web.archive.org/web/20171101011738/https://www.thespruce.com/american-crow-or-common-raven-386345 |archive-date=November 1, 2017 |access-date=June 2, 2023 |website=The Spruce}}</ref> thumb|The skull of an American crowCrows 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 uses a different area in its brain, the pallium,<ref>{{cite journal|last1=Güntürkün|first1=Onur|last2=von Eugen|first2=Kaya|last3=Packheiser|first3=Julian|last4=Pusch|first4=Ronald|title=Avian pallial circuits and cognition: A comparison to mammals|journal=Current Opinion in Neurobiology|volume=71|year=2021|pages=29–36|doi=10.1016/j.conb.2021.08.007|pmid=34562800 |doi-access=free}}</ref><ref name=tool>{{cite journal|last1=Pendergraft|first1=LomaJohn T.|last2=Marzluff|first2=John M.|last3=Cross|first3=Donna J.|last4=Shimizu|first4=Toru|last5=Templeton|first5=Christopher N.|title=American crows that excel at tool use activate neural circuits distinct from less talented individuals|journal=Nature Communications|volume=14|article-number=6539|year=2023|issue=1 |doi=10.1038/s41467-023-42203-8|pmid=37863938 |doi-access=free|pmc=10589215 |bibcode=2023NatCo..14.6539P }}</ref> to perform similar tasks.<ref>{{cite journal |first=Amanda|last=Heidt|title=Like humans, these big-brained birds may owe their smarts to long childhoods |url=https://www.science.org/content/article/humans-these-big-brained-birds-may-owe-their-smarts-long-childhoods|journal=Science|doi=10.1126/science.abd2209|date=8 June 2020}}</ref><ref>{{cite web |first=Chris|last=Baraniuk|date=11 December 2019|title=Crows have long been considered cunning. But their intelligence may be far more advanced than we ever thought possible.|url=https://www.bbc.com/future/article/20191211-crows-could-be-the-smartest-animal-other-than-primates|website=BBC|access-date=6 March 2025}}</ref> They can remember and identify people based on their appearance.<ref>{{Cite web |last=Angell |first=John M. Marzluff and Tony |date=2012-06-07 |title=How Crows Recognize Individual Humans, Warn Others, and Are Basically Smarter Than You |url=https://www.popsci.com/science/article/2012-06/how-crows-recognize-individual-humans-warn-others-and-are-basically-smarter-you/ |access-date=2025-10-28 |website=Popular Science |language=en-US}}</ref><ref>{{Cite web |date=2018-10-23 |title=Crows Are as Intelligent as a Seven-Year-Old Child |url=https://www.nathab.com/blog/crows-are-as-intelligent-as-a-seven-year-old-child |access-date=2025-10-28 |language=en-US}}</ref>

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.<ref name="cdep2001" /> The West Nile virus is a major cause of death in crows.<ref>{{Cite journal |last1=Yaremych |first1=Sarah A. |last2=Warner |first2=Richard E. |last3=Mankin |first3=Phil C. |last4=Brawn |first4=Jeff D. |last5=Raim |first5=Arlo |last6=Novak |first6=Robert |date=April 2004 |title=West Nile virus and high death rate in American crows |journal=Emerging Infectious Diseases |volume=10 |issue=4 |pages=709–711 |doi=10.3201/eid1004.030499 |issn=1080-6040 |pmc=3323091 |pmid=15200865 |bibcode=2004EIDis..10..709Y }}</ref>

=== Distribution and habitat === The American crow has a large range, extending 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.<ref name="iucn" /> They have also been recorded in Bermuda from 1876 onwards.<ref>{{cite book |last=Long |first=John L. |title=Introduced Birds of the World: The worldwide history, distribution and influence of birds introduced to new environments |publisher=Reed |year=1981 |isbn=0-589-50260-3 |location=Terrey Hills, Sydney |page=354}}</ref> 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<ref>{{Cite journal |last=Houston |first=C.S. |date=1977 |title=Changing Patterns of Corvidae on the Prairies |url=https://bluejayjournal.ca/index.php/bluejay/article/view/4262 |journal=Blue Jay |volume=35 |issue=3 |doi=10.29173/bluejay4262|doi-access=free }}</ref> as well as range expansions of other species of birds such as the barred owl.<ref>{{Cite journal |last=Livezey |first=Kent B. |date=2009 |title=Range Expansion of Barred Owls, Part II: Facilitating Ecological Changes |url=https://www.jstor.org/stable/20491442 |journal=The American Midland Naturalist |volume=161 |issue=2 |pages=323-349}}</ref><ref>{{Cite journal |last=Livezey |first=Kent B. |date=2010 |title=Killing Barred Owls to Help Spotted Owls II: Implications for Many Other Range-Expanding Species |url=https://doi.org/10.1898/NWN09-38.1 |journal=Northwestern Naturalist |volume=91 |issue=3 |pages=251-270}}</ref> The American crow inhabits virtually all types of country – from wilderness, farmland, parks, and open woodland to towns and major cities – and is absent only from tundra habitat.<ref name=":1" /><ref>{{Cite web|title=AMERICAN CROW {{!}} The Texas Breeding Bird Atlas|url=https://txtbba.tamu.edu/species-accounts/american-crow/|website=txtbba.tamu.edu|access-date=2025-11-30|quote=American Crows breed in at least some parts of all the 48 contiguous United States, southern Canada, and northern North American Baja California, Mexico, although densities are lower on the western Great Plains and in the intermountain west and the southwestern deserts (Verbeek and Caffrey 2002, Sauer et al. 2005).}}</ref> The American crow is a permanent resident in most of the US, but most Canadian birds migrate some distance southward in winter.<ref name=":1">{{Cite web |title=American Crow {{!}} Audubon Field Guide |url=https://www.audubon.org/field-guide/bird/american-crow |access-date=2025-10-28 |website=www.audubon.org |language=en}}</ref> Outside the nesting season, these birds often gather in large communal roosts of thousands or even millions of crows at night.<ref>{{cite web |last=Di Dilvestro |first=Roger |title=Something To Crow About |url=http://www.nwf.org/News-and-Magazines/National-Wildlife/Birds/Archives/2008/Bird-Watching.aspx |publisher=National Wildlife Federation}}</ref><ref name="Caccamise Reed Stouffer 1997 pp. 628–637">{{cite journal | last1=Caccamise | first1=Donald F. | last2=Reed | first2=Lisa M. | last3=Stouffer | first3=Philip C. | title=Roosting Behavior and Group Territoriality in American Crows | journal=The Auk | volume=114 | issue=4 | date=1997 | doi=10.2307/4089282 | pages=628–637| jstor=4089282 }}</ref>

Studying the behavior of American crows is laborious due to the difficulty in catching them, resulting in much of their behavior, including daily routine, migration, molting, survivorship, age of first breeding, nestling development, and the nature of nesting helpers, being poorly studied.<ref name="Verbeek-2021" /><ref>{{Cite journal |last1=Kirchmeir |first1=Alice |last2=Uhl |first2=Florian |last3=Bugnyar |first3=Thomas |last4=Schwab |first4=Christine |date=2019-01-02 |title=Catching crows: seasonality, techniques and the influence of social behaviour |url=https://doi.org/10.1080/03078698.2019.1759906 |journal=Ringing & Migration |volume=34 |issue=1 |pages=1–7 |doi=10.1080/03078698.2019.1759906 |issn=0307-8698|url-access=subscription }}</ref>

===Diet=== The American crow is omnivorous.<ref name=":1" /> It will feed on invertebrates of all types, carrion, scraps of human food, fruits,<ref name="auto">{{cite web | url=https://animaldiversity.org/accounts/Corvus_brachyrhynchos/ | title=Corvus brachyrhynchos (American crow) | website=Animal Diversity Web }}</ref> 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,<ref name="auto" /> 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.<ref name = parr2005/> The American crow is one of only a few species of birds that have been observed modifying and using tools to obtain food.<ref name=Caffrey2000/>

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.<ref name = parr2005 />

===Reproduction=== 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.<ref name="segelken">{{Cite web|title=Researcher studies the American crow|url=http://www.news.cornell.edu/chronicle/97/4.10.97/crow.html|website=www.news.cornell.edu|access-date=2025-11-30|archive-url=https://web.archive.org/web/20120926112826/http://www.news.cornell.edu/chronicle/97/4.10.97/crow.html|archive-date=2012-09-26|url-status=live}}</ref> 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.<ref name=":2" /> Most do not leave the nest to breed for four to five years.<ref name = segelken />

The nesting season starts early, with some birds incubating eggs by early April.<ref name=":2" /> 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.<ref>{{Cite web |date=2016-03-29 |title=Everything you want to know about crow nests |url=https://corvidresearch.blog/2016/03/29/everything-you-want-to-know-about-crow-nests/ |access-date=2025-10-29 |language=en}}</ref><ref name=":0">{{Cite web |title=Crow Biology {{!}} Internet Center for Wildlife Damage Management |url=https://icwdm.org/species/birds/crows/crow-biology/ |access-date=2025-10-29 |language=en}}</ref> 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 both North American eagles.<ref name="Verbeek-2021" /> They may be attacked by predators such as coyotes or bobcats at carrion when incautious, although this is even rarer.<ref name="Sullivan" /><ref>{{Cite web |author=Ron J. Johnson |date=1994-08-03 |title=Crows, American |url=http://icwdm.org/handbook/birds/AmericanCrows.asp |archive-url=https://web.archive.org/web/20170716182243/http://icwdm.org/handbook/birds/AmericanCrows.asp |archive-date=2017-07-16 |website=icwdm.org |access-date=2025-10-29}}</ref> American crows have been shown to be more wary of disturbances in urban environments.<ref>{{Cite journal |last1=Knight |first1=Richard L. |last2=Grout |first2=Daniel J. |last3=Temple |first3=Stanley A. |date=1987 |title=Nest-Defense Behavior of the American Crow in Urban and Rural Areas |url=https://www.jstor.org/stable/1368772 |journal=The Condor |volume=89 |issue=1 |pages=175–177 |doi=10.2307/1368772 |jstor=1368772 |bibcode=1987Condo..89..175K |issn=0010-5422}}</ref> The American crow experiences inbreeding depression, yet research indicates they maintain a preference for such behavior.<ref name="Townsend2019">{{cite journal |vauthors=Townsend AK, Taff CC, Jones ML, Getman KH, Wheeler SS, Hinton MG, Logsdon RM |date=March 2019 |title=Apparent inbreeding preference despite inbreeding depression in the American crow |url= |journal=Mol Ecol |volume=28 |issue=5 |pages=1116–1126 |bibcode=2019MolEc..28.1116T |doi=10.1111/mec.14866 |pmid=30222228}}</ref>

<gallery widths="200" heights="160" mode="packed"> File:The Childrens Museum of Indianapolis - American crow egg.jpg|Egg, in the collection of the Children's Museum of Indianapolis File:Corvus caurinus - June 2007.jpg|alt=Bird on a human's hand|A fledgling, of the Northwestern subtype File:American Crow imported from iNaturalist photo 250510645 on 5 December 2024.jpg|Leucistic crow feeding its offspring </gallery>

===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. It was accidentally introduced to North America in 1999, apparently by an air traveller who was infected by a mosquito bite after arrival. It is estimated that the American crow population has dropped by up to 45% since 1999.<ref>{{cite journal |last1=LaDeau |first1=Shannon L. |last2=Kilpatrick |first2=A. Marm |last3=Marra |first3=Peter P. |title=West Nile virus emergence and large-scale declines of North American bird populations |journal=Nature |volume=447 |pages=710–713 |year=2007 |doi=10.1038/nature05829 |pmid=17507930 |issue=7145|bibcode=2007Natur.447..710L |s2cid=4337661 }}</ref> Despite this decline, the crow is considered a species of least concern.<ref>{{Cite news | first=David | last=Deen | title=The crow – a sociable bird with a long memory |work= The Chronicle | location=Barton, Vermont | page= 34 | date=December 12, 2012}}</ref> The disease runs most rampant in the subtropical conditions that 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.<ref name=CLO/><ref name=Caffrey2005/> 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.<ref name = cdep2001 />

=== Intelligence === American crows, like other corvids, are highly cunning and inquisitive. They can 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.<ref name="Verbeek-2021" /> American crows have been observed using and modifying tools;<ref>{{Cite journal|last=Caffrey|first=Carolee|date=June 2000|title=Tool Modification and Use by an American Crow|url=https://bioone.org/journals/the-wilson-bulletin/volume-112/issue-2/0043-5643_2000_112_0283_TMAUBA_2.0.CO_2/Tool-Modification-and-Use-by-an-American-Crow/10.1676/0043-5643(2000)112[0283:TMAUBA]2.0.CO;2.full|journal=The Wilson Bulletin|volume=112|issue=2|pages=283–284|doi=10.1676/0043-5643(2000)112[0283:TMAUBA]2.0.CO;2|s2cid=86124230 |issn=0043-5643|url-access=subscription}}</ref> however, unlike the Hawaiian and New Caledonian crow, this behavior is not inherent.<ref>{{Cite web |last=Kenna Hughes-Castleberry |first=Ars |date=2023-12-14 |title=What happens in a crow's brain when it uses tools? |url=https://arstechnica.com/science/2023/12/what-happens-in-a-crows-brain-when-it-uses-tools/ |access-date=2025-10-29 |website=Ars Technica |language=en}}</ref> Female crows have been observed to be better at using tools, according to a 2023 study.<ref name=tool/> American crows have also been noted for their ability to play, such as snowboarding using tree bark.<ref>{{Cite web |last=O'Grady |first=Cathleen |date=2016-01-28 |title=Crows: The tail-pulling, food-stealing bird prodigies |url=https://arstechnica.com/science/2016/01/crows-the-tail-pulling-food-stealing-bird-prodigies/ |access-date=2025-10-28 |website=Ars Technica |language=en}}</ref><ref>{{Cite web |date=2015-03-16 |title=Crow curiosities: Do crows play and why? |url=https://corvidresearch.blog/2015/03/16/crow-curiosities-do-crows-play-and-why/ |access-date=2025-10-28 |language=en}}</ref>

==Status and management== thumb|upright|Brooklyn Museum – American crow – John J. Audubon

The intelligence and adaptability of the American crow have insulated it from threats, and it is instead considered an agricultural pest.<ref name="Verbeek-2021" /> 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.<ref name="iucn" />

Crows have been killed in large numbers by humans, both for recreation and as part of organized campaigns of extermination.<ref name="Campbell" /> In Canada, American crows have no protections, aside from Quebec, which bans their hunting during the nesting season.<ref name="Verbeek-2021" /> Laws on 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 crops did not decrease; 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.<ref name="Verbeek-2021" />

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.<ref>{{Cite web |title=Crow Damage Prevention and Control Methods {{!}} Internet Center for Wildlife Damage Management |url=https://icwdm.org/species/birds/crows/crow-damage-prevention-and-control-methods/ |access-date=2025-10-28 |language=en}}</ref> 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.<ref name="Verbeek-2021" /> There is some suggestion that they may be a benefit to farmers by eating insect pests and chasing off livestock predators like hawks.<ref name="Sullivan">{{Cite web|last=Sullivan|first=Emily|title=The Glorious American Crow - Romanticism at SU|url=https://www.romanticismatsu.com/the-glorious-american-crow%e2%80%8b/|url-status=live|access-date=2021-10-23|language=en-US|archive-url=https://web.archive.org/web/20200928111827/https://www.romanticismatsu.com/the-glorious-american-crow%E2%80%8B/|archive-date=2020-09-28}}</ref>

== Role in human cultures == {{See also|Cultural depictions of ravens}}

Crows are used as a motif in some human cultures, often associated with death, thieves, graveyards, bad luck, and other negative connotations.<ref name="Sullivan" /> American crows are sometimes considered a pest, often due to their loud calls.<ref>{{Cite web |last=Staff|first=P. M. P.|date=2021-08-27|title=Pest Spotlight: American Crow|url=https://www.mypmp.net/pest-spotlight-american-crow/|access-date=2025-10-28|website=Pest Management Professional|language=en-US}}</ref><ref>{{Cite web |title=American Crow|url=https://abcbirds.org/bird/american-crow/|access-date=2025-10-28|website=American Bird Conservancy|language=en}}</ref> However, in other cultures, like Native American folklore, crows are considered good luck, noted for their intelligence.<ref>{{Cite web |title=Native American Indian Crow Legends, Meaning and Symbolism from the Myths of Many Tribes|url=https://www.native-languages.org/legends-crow.htm|access-date=2025-10-28|website=www.native-languages.org}}</ref> Similarly, they are also 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.<ref>{{cite web |url=https://www.cbs19news.com/story/44652969/crow-symbolism-meaning-totem-spirit-omens|title=Crow Symbolism & Meaning (+Totem, Spirit & Omens)|access-date=26 February 2023|website=CBS 19 News}}</ref> Crows are also featured in Aesop's Fables, in stories such as "The Crow and the Pitcher", and "The Fox and the Crow".<ref>{{Cite web |title=Library of Congress Aesop Fables|url=https://www.read.gov/aesop/012.html|access-date=2025-10-28|website=www.read.gov}}</ref>

==References== {{Reflist|colwidth=30em|refs= <ref name=Campbell>{{cite book|author =Campbell, Robert Wayne|author2 =Canadian Wildlife Service|name-list-style =amp|chapter=American Crow|title=The Birds of British Columbia: Passerines: flycatchers through vireos|publisher=UBC Press|year=1997|isbn=978-0-7748-0572-8|chapter-url=https://books.google.com/books?id=OlCGHnhHoM0C&pg=PA227 |page=227}}</ref>

<ref name=Caffrey2000>{{cite journal|author =Caffrey, Carolee|year=2000|title= Tool Modification and Use by an American Crow|journal=Wilson Bull.|volume=112|issue=2|pages= 283–284|doi=10.1676/0043-5643(2000)112[0283:TMAUBA]2.0.CO;2|s2cid=86124230 }}</ref>

<ref name=Caffrey2005>{{cite journal|author1=Caffrey, Carolee |author2=Smith, Shauna C.R. |author3=Weston, Tiffany J. |year=2005|title= West Nile Virus Devastates an American Crow Population|journal=Condor|volume=107|issue=1|pages= 128–132|doi=10.1650/7646|s2cid=85419982 |doi-access=free}}</ref>

<ref name=cdep2001>Connecticut Department of Environmental Protection (2001): [http://www.mosquito.state.ct.us/fact/crowfact.htm American Crow Fact Sheet] {{webarchive |url=https://web.archive.org/web/20061105022804/http://www.mosquito.state.ct.us/fact/crowfact.htm |date=November 5, 2006 }}. Version of 2001. Retrieved 2006-October-25.</ref>

<ref name=CLO>Cornell Lab of Ornithology (2002): Bird Guide – [https://www.birds.cornell.edu/AllAboutBirds/BirdGuide/American_Crow_dtl.html American Crow]. Retrieved 2006-October-24.</ref>

<ref name=Dick>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.</ref>

<ref name=Liddell>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}}.</ref>

<ref name = m&b1994>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}}.</ref>

<ref name = parr2005>{{cite web|author =C. Parr|year=2005|publisher=Animal Diversity Web|url=http://animaldiversity.org/accounts/Corvus_brachyrhynchos/|title=Corvus brachyrhynchos|access-date=13 September 2015}}</ref> }}

==Bibliography== * Goodwin, Derek & Gillmor, Robert (1976): ''Crows of the World'' (1st ed.). University of Washington Press, Seattle.

==External links== {{Commons category|Corvus brachyrhynchos}} {{Wikispecies|Corvus brachyrhynchos}} * [https://web.archive.org/web/20050228104627/https://www.skullsite.com/images/dbimages/large/corvusbrachyrhynchos_s.jpg Skull of American Crow] * [https://www.flickr.com/search/groups/?m=pool&w=42637302%40N00&q=corvus+brachyrhynchos Pictures of American Crow on Birds of the World at Flickr] * {{InternetBirdCollection|american-crow-corvus-brachyrhynchos|American Crow}} * {{EOL}} * [https://web.archive.org/web/20051222121959/https://www.shades-of-night.com/aviary/sounds/crow2.wav American Crow call] * {{VIREO|American+Crow|American Crow}} * [https://web.archive.org/web/20051221233017/https://www.shades-of-night.com/aviary/sounds/crow1.wav Northwestern Crow call (two birds)]

Category:Articles containing video clips Category:Birds described in 1822 Category:Birds of North America Category:Birds of the United States Category:Corvus Category:Least concern biota of the United States Category:Taxa named by Christian Ludwig Brehm Category:Tool-using animals