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What the sources say

American CrowCorvus brachyrhynchos

Every figure, record and mechanism on the American Crow profile was written from a source, and this is the working table behind it: 50 claims checked word for word against these sources. The left column is what the page says. The right column is the source's own words, copied, not paraphrased; a ... marks a cut and[brackets] an insertion. Open any source and check it yourself.

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Source
01

The IUCN Red List of Threatened Species 2018

Corvus brachyrhynchos. The IUCN Red List of Threatened Species 2018: e.T22705990A131945410.

The page saysLeast Concern
The source saysIUCN Red List category: Least Concern (LC).Note: stats.conservationStatus

Source
02

Animal Diversity Web, University of Michigan

Corvus brachyrhynchos (American crow). Animal Diversity Web, University of Michigan.

The page saysOpen land with nearby trees, farms, suburbs and city parks across the lower part of Canada and the continental United States
The source saysAmerican crows prefer open areas with nearby trees. Agricultural and grassland areas are ideal habitat for crows to forage for their food.Note: stats.habitat
The page saysOpen land with nearby trees, farms, suburbs and city parks across the lower part of Canada and the continental United States
The source saysAmerican crows thrive in suburban neighborhoods and urban parks, as well as in coastal habitats.Note: stats.habitat
The page saysOpen land with nearby trees, farms, suburbs and city parks across the lower part of Canada and the continental United States
The source saysThey can be found in the lower part of Canada and through the continental United States.Note: stats.habitat
The page saysOmnivore: insects and their larvae, worms, fruit, grains, nuts, carrion, and the eggs and nestlings of smaller songbirds
The source saysDuring the breeding season, American crows consume insects and their larvae, worms, fruits, grains, and nuts.Note: stats.diet
The page saysOmnivore: insects and their larvae, worms, fruit, grains, nuts, carrion, and the eggs and nestlings of smaller songbirds
The source saysThey also are significant nest predators, preying on the eggs and nestlings of smaller songbirds.Note: stats.diet
The page saysOmnivore: insects and their larvae, worms, fruit, grains, nuts, carrion, and the eggs and nestlings of smaller songbirds
The source saysthey more likely to scavenge carrion such as roadkillNote: stats.diet
The page saysAn adult American crow is completely black, 41 to 53 cm long, and weighs 311 to 623 g.
The source saysAdult American crows are completely black birds
The page saysIts black bill ends in a slight hook, and stiff bristles sit over the nostrils.
The source saysThe bill is also black with a slight hook on the end. Stiff bristles cover their nostrils.
The page saysRavens look similar but are much larger, with a hoarser voice.
The source saysAmerican crows can be distinguished from common ravens (Corvus corax) most easily by size (ravens are much larger), by voice (ravens are hoarser)
The page saysIts call is a set of loud, harsh caws, and the shorter, sharper ones, called "kos", are probably alarm calls.
The source saysThey have a complex system of loud, harsh caws
The page saysIts call is a set of loud, harsh caws, and the shorter, sharper ones, called "kos", are probably alarm calls.
The source saysShorter and sharper caws called "kos" are probably alarm or alert calls.
The page saysFemales lay 4 to 5 eggs, which hatch after 18 days.
The source saysFemales lay 4 to 5 light green colored eggs with brown markings. ... Eggs hatch after 18 days.
The page saysThe young leave the nest at about 35 days old
The source saysThe young fledge (leave the nest) when they are approximately 35 days old.
The page saysthey have blue eyes that darken as they grow up.
The source saysYoung crows are about the same size as adults, but have blue eyes and pink inside the mouth. Both the eyes and mouth darken as the bird becomes an adult.
The page saysAmerican crows are omnivores, eating plants and animals.
The source saysAmerican crows are omnivores
The page saysWhen breeding, crows eat insects and larvae, worms, fruit, grain and nuts.
The source saysDuring the breeding season, American crows consume insects and their larvae, worms, fruits, grains, and nuts.
The page saysThey will hunt frogs, mice and young rabbits, but they are more likely to scavenge carrion such as roadkill.
The source saysThey actively hunt and prey on small animals such as frogs, mice, and young rabbits, though they more likely to scavenge carrion such as roadkill.
The page saysTo crack a nut, a crow pins it under one foot and hammers it with its bill.
The source saysCrows will hold a nut under one foot and strike it with the bill to open it.
The page saysa crow flies high and drops it on a hard surface
The source saysa crow will fly high with it and drop it on a hard surface
The page saysThey also cache food, hiding it in scattered spots instead of one place.
The source saysAmerican crows store food items such as meat and nuts in short-term caches. Caches are hiding places that are scattered around, rather than in one place.
The page saysAmerican crows are native across North America, including the lower part of Canada and the continental United States.
The source saysAmerican crows are native to the Nearctic region all over North America. They can be found in the lower part of Canada and through the continental United States.
The page saysThey like open areas with nearby trees, and they thrive in suburban neighborhoods and urban parks.
The source saysAmerican crows prefer open areas with nearby trees.
The page saysThey like open areas with nearby trees, and they thrive in suburban neighborhoods and urban parks.
The source saysAmerican crows thrive in suburban neighborhoods and urban parks, as well as in coastal habitats.
The page saysThey are cooperative breeders: some offspring stay close to where they were born and help raise young.
The source saysAmerican crows have an unusual social system - they are cooperative breeders. This means that they may stay close to the place where they were born to help raise young and defend the area against predators.
The page saysFaced with a predator, crows gang up to chase it and yell at it, which is known as mobbing.
The source saysCrows will group together to vocally harass and chase predators. This behavior is called mobbing.
The page saysIn winter, roosts can gather tens to hundreds of thousands of crows.
The source saysLarge numbers of crows, from tens to hundreds of thousands, will assemble in the late afternoon hours in an area with large trees.
The page saysIt is an omnivore. Insects, worms, fruit, grains and nuts are on the menu, along with carrion such as roadkill and the eggs and young of smaller songbirds.
The source saysAmerican crows are omnivoresNote: FAQ
The page saysIt is an omnivore. Insects, worms, fruit, grains and nuts are on the menu, along with carrion such as roadkill and the eggs and young of smaller songbirds.
The source saysDuring the breeding season, American crows consume insects and their larvae, worms, fruits, grains, and nuts.Note: FAQ
The page saysIt is an omnivore. Insects, worms, fruit, grains and nuts are on the menu, along with carrion such as roadkill and the eggs and young of smaller songbirds.
The source saysthough they more likely to scavenge carrion such as roadkillNote: FAQ
The page saysIt is an omnivore. Insects, worms, fruit, grains and nuts are on the menu, along with carrion such as roadkill and the eggs and young of smaller songbirds.
The source saysThey also are significant nest predators, preying on the eggs and nestlings of smaller songbirds.Note: FAQ
The page saysFaced with a predator, crows gang up to chase it and yell at it
The source saysCrows will group together to vocally harass and chase predators.Note: vibe.reason

Source
03

AnAge: The Animal Ageing and Longevity Database, Build 15, Human Ageing Genomic Resources

AnAge entry for Corvus brachyrhynchos. AnAge: The Animal Ageing and Longevity Database, Build 15, Human Ageing Genomic Resources.

The page saysAnAge records a maximum longevity of 20 years for the species.
The source saysMaximum longevity 20 years
The page saysThe AnAge database puts the species' maximum longevity at 20 years.
The source saysMaximum longevity 20 yearsNote: FAQ

Source
04

Cornell, Marzluff & Pecoraro 2011

Cornell, Marzluff & Pecoraro (2011). Social learning spreads knowledge about dangerous humans among American crows. Proceedings of the Royal Society B: Biological Sciences.

The page saysLearns a dangerous human face, and the scolding spreads from crow to crow.
The source saysAmerican crows (Corvus brachyrhynchos) use both sources of information to learn the facial features of a dangerous person.Note: tagline
The page saysLearns a dangerous human face, and the scolding spreads from crow to crow.
The source saysLater recognition of dangerous masks by lone crows that were never captured is consistent with horizontal social learning.Note: tagline
The page saysLearns a threatening face and passes the lesson on to other crows
The source saysIndependent scolding by young crows, whose parents had conditioned them to scold the dangerous mask, demonstrates vertical social learning.Note: stats.superpower
The page saysResearchers near Seattle wore a unique mask while they trapped, banded and released crows.
The source saysWe exposed wild crows to a novel 'dangerous face' by wearing a unique mask as we trapped, banded and released 7-15 birds at five study sites near Seattle, WA, USA.
The page saysCrows that had been caught scolded the mask right away.
The source saysAn immediate scolding response to the dangerous mask after trapping by previously captured crows demonstrates individual learning
The page saysLater, lone crows that had never been caught recognized the mask too, which fits with learning from other crows.
The source saysLater recognition of dangerous masks by lone crows that were never captured is consistent with horizontal social learning.
The page saysYoung crows whose parents had taught them to scold the mask joined in on their own.
The source saysIndependent scolding by young crows, whose parents had conditioned them to scold the dangerous mask, demonstrates vertical social learning.
The page saysOver five years at one site, scolding of the "dangerous" mask doubled in frequency and spread at least 1.2 km from where it began.
The source saysLearning enabled scolding to double in frequency and spread at least 1.2 km from the place of origin over a 5 year period at one site.
The page saysCrows can learn a dangerous face. In the Seattle mask study, birds that had been trapped scolded the mask, as did crows that had never been caught and young crows taught by their parents.
The source saysAn immediate scolding response to the dangerous mask after trapping by previously captured crows demonstrates individual learningNote: FAQ
The page saysCrows can learn a dangerous face. In the Seattle mask study, birds that had been trapped scolded the mask, as did crows that had never been caught and young crows taught by their parents.
The source saysLater recognition of dangerous masks by lone crows that were never captured is consistent with horizontal social learning.Note: FAQ
The page saysCrows can learn a dangerous face. In the Seattle mask study, birds that had been trapped scolded the mask, as did crows that had never been caught and young crows taught by their parents.
The source saysIndependent scolding by young crows, whose parents had conditioned them to scold the dangerous mask, demonstrates vertical social learning.Note: FAQ
The page saysa scolding one crow learns spreads to crows that were never caught
The source saysLater recognition of dangerous masks by lone crows that were never captured is consistent with horizontal social learning.Note: vibe.reason

Source
05

Yaremych et al. 2004

Yaremych et al. (2004). West Nile Virus and High Death Rate in American Crows. Emerging Infectious Diseases.

The page saysIn a 2002 Illinois study, more than two thirds of the crows studied died of West Nile virus infection.
The source saysMore than two thirds of our crows died of WNV infectionNote: study of crows captured in Champaign/Urbana, Illinois, 2002
The page saysIn a 2002 Illinois study, more than two thirds of the crows studied died of West Nile virus infection.
The source saysWe monitored the emergence and prevalence of WNV infection in American Crows ( Corvus brachyrhynchos ) in Illinois during the spring and summer of 2002

Source
06

National Audubon Society

American Crow. National Audubon Society.

The page saysAn adult American crow is completely black, 41 to 53 cm long, and weighs 311 to 623 g.
The source saysLength: 16–21 in (41–53 cm)
The page saysAn adult American crow is completely black, 41 to 53 cm long, and weighs 311 to 623 g.
The source saysweight: 11–22 oz (311–623 g)

How the table was made: a writer drafted the profile from these sources and logged each claim with its quote, a reviewer with nothing but this table checked every sentence said no more than its quote, and a script confirmed each quote appears word for word in the source. The method is in the site'sAbout page.