Carrion Crow

The carrion crow (Corvus corone) is a medium-sized and exceptionally adaptable crow distributed across much of Eurasia. Adults are roughly 44–52 cm long and average around half a kilogram, although size varies geographically. The species includes strikingly different plumage forms. The western nominate subspecies, western carrion crow (C. c. corone), is entirely black, while hooded crow (C. c. cornix) and related eastern forms have a pale grey body contrasting with a black head, throat, wings and tail.

These forms are easy to recognise in the field despite belonging to the same species. Where all-black and grey-and-black populations meet, they hybridise and produce birds with intermediate plumage. The species is also distinguished from the larger common raven (Corvus corax) by its smaller size, less massive bill and more rounded tail.

Hooded and carrion crows have repeatedly moved between species and subspecies status. They were widely treated as separate species from the early 2000s, but AviList reunited them in 2025 as subspecies within Corvus corone. This treatment is unchanged in AviList v2025b, released in 2026.

The European hybrid zone helps explain why the classification has been difficult. A genomic study published in 2019 examined more than 400 birds from the hybrid zone and found extensive gene flow across most of the genome even though plumage remained sharply differentiated. Much of the colour variation was linked to only a few genomic regions kept different by natural selection. Major differences in these pigmentation-related regions can therefore persist while the rest of the genome mixes much more freely.

Carrion crows use an exceptionally broad range of habitats, including farmland, pasture, woodland edges, moorland, coasts, wetlands, mountains, villages and cities. They favour landscapes that combine open ground for feeding with trees, cliffs or structures suitable for resting and nesting.

The species succeeds in both relatively natural and heavily modified landscapes because it is not tied to one narrow habitat or food source. Local numbers instead depend strongly on access to good feeding areas, safe nest sites and resources that change through the year.

Carrion crows are omnivorous and opportunistic. They eat insects and other invertebrates, earthworms, grain and seeds, fruit, carrion, eggs, nestlings, small vertebrates and discarded human food. Individuals quickly learn where temporary food sources appear, from ploughed fields and shorelines to roadsides and urban parks.

The birds also use flexible feeding techniques. They can drop or manipulate hard-shelled food to open it, and surplus food may be cached for later use. A Norwegian study published in 1988 documented hooded crows storing food and later returning to recover it, showing how food caches can supplement an already broad diet.

Most breeding carrion crows form long-term territorial pairs, while non-breeders may gather in loose groups and communal roosts. Social organisation varies geographically. In parts of northern Spain, family groups can remain together and breed cooperatively, with additional birds helping to defend territories and feed the young. A transfer experiment published in 2002 showed how flexible this system can be: five of six young from a non-cooperative Swiss population remained on their foster parents’ territories when raised in a cooperative Spanish population, and two later became helpers.

A GPS study published in 2025 followed 80 first-year carrion crows in Paris and documented fission–fusion dynamics, in which groups repeatedly split and re-form. Young birds met again around feeding sites and communal roosts, while many continued to use their parents’ territories through winter before becoming more mobile in spring. The same birds can therefore associate repeatedly without belonging to a permanently stable flock.

Crows are unusually flexible learners and problem-solvers. In a 2024 experiment, trained carrion crows learned to produce a planned sequence of one to four calls in response to cues representing different numbers. The birds therefore had to connect the number they perceived with a specific number of calls they produced themselves.

Another study published in 2024 showed that hooded crows could make pieces that matched a previously learned template in colour and relative size. Together, these experiments reveal cognitive abilities that help explain how well crows cope with complex and rapidly changing environments.

The species is resident or only partly migratory across much of its range. Adults in western and central Europe are commonly sedentary, while birds from colder northern and eastern regions are more likely to move southward or toward coasts in autumn and winter.

Movements vary with age, region, weather and food rather than following one fixed migration pattern. Young birds and non-breeders can range more widely than established territorial adults.

Carrion crows normally breed as territorial pairs and raise one brood per year. The large stick nest is most often built high in a tree, although cliffs, pylons and buildings may also be used. A typical clutch contains 3–5 eggs, with some regional variation. The female does most of the incubation for roughly 18–20 days, while the male supplies food and helps defend the territory.

Both parents feed the chicks, which normally remain in the nest for about four to five weeks and continue to depend on the adults after fledging. Cooperative breeding occurs in some populations, especially in northern Spain, where additional group members may help with territory defence and feeding the young, but this is not the normal breeding system throughout the range.

Carrion crows have adapted particularly well to human-modified landscapes. Farms, roads, parks and cities provide abundant food, open ground for foraging and many potential nesting sites. Urban birds can become markedly tolerant of people and adjust where and when they feed and how closely they allow people to approach.

The same adaptability can bring the species into conflict with people. Crows may be persecuted because they take eggs and young of gamebirds or other wildlife, damage crops locally or gather around refuse. Their effects vary greatly among places, however, and high crow numbers alone do not show that crows are the main cause when another species declines.

The carrion crow is classified as least concern on the IUCN Red List. It has an enormous Eurasian range and remains common across large parts of both the all-black and hooded forms’ distributions.

The 2025 update from the Pan-European Common Bird Monitoring Scheme, based on data through 2024, shows a 22% long-term increase in the European breeding index, while the change over 2015–2024 was a small decline of 2%. The species has therefore remained broadly stable at continental scale in the most recent decade despite the longer-term increase.