---
title: "What the sources say about the American Crow | AnimalTracks.wiki"
description: "50 claims from the American Crow profile, each beside the words of the source that backs it."
image: "https://animaltracks.wiki/images/animals/american-crow-1.webp"
canonical: "https://animaltracks.wiki/animals/american-crow/sources/"
---

# What the sources say about the American Crow (*Corvus brachyrhynchos*)

> 50 claims from the American Crow profile, each beside the words of the source that backs it. A "..." marks a cut in a quote and [brackets] an insertion.

Profile: [American Crow](https://animaltracks.wiki/animals/american-crow/)

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

https://doi.org/10.2305/iucn.uk.2018-2.rlts.t22705990a131945410.en

| The page says | The source says |
| :--- | :--- |
| Least Concern | IUCN Red List category: Least Concern (LC). (note: stats.conservationStatus) |

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

https://animaldiversity.org/accounts/Corvus_brachyrhynchos/

| The page says | The source says |
| :--- | :--- |
| Open land with nearby trees, farms, suburbs and city parks across the lower part of Canada and the continental United States | American crows prefer open areas with nearby trees. Agricultural and grassland areas are ideal habitat for crows to forage for their food. (note: stats.habitat) |
| Open land with nearby trees, farms, suburbs and city parks across the lower part of Canada and the continental United States | American crows thrive in suburban neighborhoods and urban parks, as well as in coastal habitats. (note: stats.habitat) |
| Open land with nearby trees, farms, suburbs and city parks across the lower part of Canada and the continental United States | They can be found in the lower part of Canada and through the continental United States. (note: stats.habitat) |
| Omnivore: insects and their larvae, worms, fruit, grains, nuts, carrion, and the eggs and nestlings of smaller songbirds | During the breeding season, American crows consume insects and their larvae, worms, fruits, grains, and nuts. (note: stats.diet) |
| Omnivore: insects and their larvae, worms, fruit, grains, nuts, carrion, and the eggs and nestlings of smaller songbirds | They also are significant nest predators, preying on the eggs and nestlings of smaller songbirds. (note: stats.diet) |
| Omnivore: insects and their larvae, worms, fruit, grains, nuts, carrion, and the eggs and nestlings of smaller songbirds | they more likely to scavenge carrion such as roadkill (note: stats.diet) |
| An adult American crow is completely black, 41 to 53 cm long, and weighs 311 to 623 g. | Adult American crows are completely black birds |
| Its black bill ends in a slight hook, and stiff bristles sit over the nostrils. | The bill is also black with a slight hook on the end. Stiff bristles cover their nostrils. |
| Ravens look similar but are much larger, with a hoarser voice. | American crows can be distinguished from common ravens (Corvus corax) most easily by size (ravens are much larger), by voice (ravens are hoarser) |
| Its call is a set of loud, harsh caws, and the shorter, sharper ones, called "kos", are probably alarm calls. | They have a complex system of loud, harsh caws |
| Its call is a set of loud, harsh caws, and the shorter, sharper ones, called "kos", are probably alarm calls. | Shorter and sharper caws called "kos" are probably alarm or alert calls. |
| Females lay 4 to 5 eggs, which hatch after 18 days. | Females lay 4 to 5 light green colored eggs with brown markings. ... Eggs hatch after 18 days. |
| The young leave the nest at about 35 days old | The young fledge (leave the nest) when they are approximately 35 days old. |
| they have blue eyes that darken as they grow up. | Young 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. |
| American crows are omnivores, eating plants and animals. | American crows are omnivores |
| When breeding, crows eat insects and larvae, worms, fruit, grain and nuts. | During the breeding season, American crows consume insects and their larvae, worms, fruits, grains, and nuts. |
| They will hunt frogs, mice and young rabbits, but they are more likely to scavenge carrion such as roadkill. | They actively hunt and prey on small animals such as frogs, mice, and young rabbits, though they more likely to scavenge carrion such as roadkill. |
| To crack a nut, a crow pins it under one foot and hammers it with its bill. | Crows will hold a nut under one foot and strike it with the bill to open it. |
| a crow flies high and drops it on a hard surface | a crow will fly high with it and drop it on a hard surface |
| They also cache food, hiding it in scattered spots instead of one place. | American 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. |
| American crows are native across North America, including the lower part of Canada and the continental United States. | American 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. |
| They like open areas with nearby trees, and they thrive in suburban neighborhoods and urban parks. | American crows prefer open areas with nearby trees. |
| They like open areas with nearby trees, and they thrive in suburban neighborhoods and urban parks. | American crows thrive in suburban neighborhoods and urban parks, as well as in coastal habitats. |
| They are cooperative breeders: some offspring stay close to where they were born and help raise young. | American 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. |
| Faced with a predator, crows gang up to chase it and yell at it, which is known as mobbing. | Crows will group together to vocally harass and chase predators. This behavior is called mobbing. |
| In winter, roosts can gather tens to hundreds of thousands of crows. | Large numbers of crows, from tens to hundreds of thousands, will assemble in the late afternoon hours in an area with large trees. |
| It 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. | American crows are omnivores (note: FAQ) |
| It 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. | During the breeding season, American crows consume insects and their larvae, worms, fruits, grains, and nuts. (note: FAQ) |
| It 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. | though they more likely to scavenge carrion such as roadkill (note: FAQ) |
| It 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. | They also are significant nest predators, preying on the eggs and nestlings of smaller songbirds. (note: FAQ) |
| Faced with a predator, crows gang up to chase it and yell at it | Crows will group together to vocally harass and chase predators. (note: vibe.reason) |

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

https://genomics.senescence.info/species/entry.php?species=Corvus_brachyrhynchos

| The page says | The source says |
| :--- | :--- |
| AnAge records a maximum longevity of 20 years for the species. | Maximum longevity 20 years |
| The AnAge database puts the species' maximum longevity at 20 years. | Maximum longevity 20 years (note: FAQ) |

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

https://doi.org/10.1098/rspb.2011.0957

| The page says | The source says |
| :--- | :--- |
| Learns a dangerous human face, and the scolding spreads from crow to crow. | American crows (Corvus brachyrhynchos) use both sources of information to learn the facial features of a dangerous person. (note: tagline) |
| Learns a dangerous human face, and the scolding spreads from crow to crow. | Later recognition of dangerous masks by lone crows that were never captured is consistent with horizontal social learning. (note: tagline) |
| Learns a threatening face and passes the lesson on to other crows | Independent scolding by young crows, whose parents had conditioned them to scold the dangerous mask, demonstrates vertical social learning. (note: stats.superpower) |
| Researchers near Seattle wore a unique mask while they trapped, banded and released crows. | We 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. |
| Crows that had been caught scolded the mask right away. | An immediate scolding response to the dangerous mask after trapping by previously captured crows demonstrates individual learning |
| Later, lone crows that had never been caught recognized the mask too, which fits with learning from other crows. | Later recognition of dangerous masks by lone crows that were never captured is consistent with horizontal social learning. |
| Young crows whose parents had taught them to scold the mask joined in on their own. | Independent scolding by young crows, whose parents had conditioned them to scold the dangerous mask, demonstrates vertical social learning. |
| Over five years at one site, scolding of the "dangerous" mask doubled in frequency and spread at least 1.2 km from where it began. | Learning 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. |
| Crows 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. | An immediate scolding response to the dangerous mask after trapping by previously captured crows demonstrates individual learning (note: FAQ) |
| Crows 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. | Later recognition of dangerous masks by lone crows that were never captured is consistent with horizontal social learning. (note: FAQ) |
| Crows 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. | Independent scolding by young crows, whose parents had conditioned them to scold the dangerous mask, demonstrates vertical social learning. (note: FAQ) |
| a scolding one crow learns spreads to crows that were never caught | Later recognition of dangerous masks by lone crows that were never captured is consistent with horizontal social learning. (note: vibe.reason) |

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

https://doi.org/10.3201/eid1004.030499

| The page says | The source says |
| :--- | :--- |
| In a 2002 Illinois study, more than two thirds of the crows studied died of West Nile virus infection. | More than two thirds of our crows died of WNV infection (note: study of crows captured in Champaign/Urbana, Illinois, 2002) |
| In a 2002 Illinois study, more than two thirds of the crows studied died of West Nile virus infection. | We monitored the emergence and prevalence of WNV infection in American Crows ( Corvus brachyrhynchos ) in Illinois during the spring and summer of 2002 |

## American Crow. National Audubon Society.

https://www.audubon.org/field-guide/bird/american-crow

| The page says | The source says |
| :--- | :--- |
| An adult American crow is completely black, 41 to 53 cm long, and weighs 311 to 623 g. | Length: 16–21 in (41–53 cm) |
| An adult American crow is completely black, 41 to 53 cm long, and weighs 311 to 623 g. | weight: 11–22 oz (311–623 g) |