Crows and jackdaws are two types of birds that belong to the corvid family. They have some similarities in appearance and behavior, but there are also key differences between the two species.
Quick Answers
Crows and jackdaws are closely related birds in the corvid family, which includes ravens, jays, and magpies. While they share some physical traits, crows and jackdaws have distinct differences in size, coloration, range, nesting habits, and behavior.
In short:
- Crows are completely black, while jackdaws have gray napes and pale eyes.
- Jackdaws are smaller than crows.
- Crows have a worldwide range, but jackdaws are concentrated in Europe, Asia, and North Africa.
- Crows build nests high up in trees, jackdaws nest in cavities like chimneys and cliff faces.
- Crows are more solitary while jackdaws are highly social and colonial.
So while crows and jackdaws share the same family, they are considered separate species with distinct characteristics. Calling a jackdaw a “crow” would not be technically accurate.
Taxonomy and Classification
Crows and jackdaws both belong to the corvid family Corvidae, which consists of over 120 species of birds including ravens, jays, magpies, and nutcrackers. This family is known for their intelligence and complex social behavior.
Within the corvid family, crows and jackdaws belong to the genus Coloeus. The scientific classifications are:
- Crows – Genus Corvus
- Jackdaws – Genus Coloeus monedula
There are several species of crows found worldwide, including the American crow, northwestern crow, Hawaiian crow, and more. Jackdaws are all considered a single species Coloeus monedula with four distinct subspecies.
While crows and jackdaws share similarities and are closely related, they are not considered the same species. They have distinct genetic differences and reproductive isolation from each other.
Physical Differences
The most obvious physical difference between crows and jackdaws is their size and coloration:
- Size: Jackdaws are smaller than crows. Jackdaws reach 13-16 inches in length with a wingspan around 30 inches. Crows are larger at 16-21 inches long with a wingspan over 3 feet.
- Color: Crows are completely black, including their eyes, beak, and feet. Jackdaws are also predominantly black but have a distinctive light gray/silver nape (back of the neck), pale eyes, and grayish legs and feet.
In flight, the paler nape of the jackdaw stands out compared to the all-black crow:
Crow | Jackdaw |
---|---|
Completely black plumage | Black plumage with pale gray nape |
Black eyes, beak, and feet | Pale eyes, grayish beak and feet |
The birds also have some subtle differences in proportions. Jackdaws have shorter, thicker bills and legs compared to crows. Their heads appear rounder and their necks shorter.
Range and Habitats
Crows are found worldwide, distributed across North America, Central America, South America, Europe, Africa, Asia, and Australia. They inhabit a wide range of habitats from forests to grasslands to urban areas.
Jackdaws have a more limited range confined mostly to Europe, Asia, and northern Africa. Their habitat is also more specific, concentrated around temperate woodlands and areas containing cliffs, buildings, and caves that provide nesting sites.
Crows | Jackdaws |
---|---|
Worldwide distribution | Limited to Europe, Asia, and northern Africa |
Diverse habitats including forests, grasslands, deserts, and urban areas | Mainly temperate woodlands and areas with cliffs/caves |
There are no crows native to Australia. The birds known as “crows” there, like the Australian raven, are more closely related to jackdaws or rooks than true crows.
Nesting and Roosting Habits
Crows typically nest high up in the tops of trees, usually 20-60 feet above the ground. Their nests are a large basket of sticks and twigs, lined with bark, moss, feathers, grass, and soft materials.
Jackdaws nest in cavities like chimneys, cliff faces, castle ramparts, and old buildings. They fill the cavity with sticks and materials to create a nest cup on the flat surface. Jackdaws do not build nests completely from scratch like crows.
Crow Nests | Jackdaw Nests |
---|---|
Large nests built high in tree branches | Smaller nests inside cavities and crevices |
Constructed entirely from sticks and twigs | Fill existing space with sticks and materials |
Crows are also more solitary roosters. They may forage in large flocks by day but roost alone or in smaller family units at night.
Jackdaws congregate in large flocks at night to roost communally inside nest cavities or on ledges. A single roost can contain over 1,000 jackdaws at once.
Behavior and Social Structure
Both crows and jackdaws exhibit complex social behavior and intelligence. However, jackdaws have a more elaborate social structure and dynamics:
- Crows are more solitary and territorial. Mated pairs defend their breeding areas.
- Jackdaws are highly gregarious and colonial. They nest, roost, and forage in large flocks.
- Jackdaw flocks have a clear hierarchy with dominant breeding pairs at the top.
- Pairs of jackdaws often form monogamous bonds for life.
- Jackdaws interact more as a group, using calls to coordinate activities and warn each other of threats.
Researchers have found that jackdaws that live in larger colonies with more social dynamics have larger brains and more neural cells associated with higher cognition and problem solving.
Vocalizations
Crows and jackdaws produce a wide range of calls and sounds:
- Crows – Loud, harsh “caw” sound; also rattles, clicks, pops, and whistles.
- Jackdaws – Hard “chak” call; also softer conversational clucks and contact calls.
Jackdaws often make a “chyak-chyak” sound in flight. Their calls are generally higher pitched than the lower croaking of crows.
Both crows and jackdaws are capable of mimicking sounds and human speech, though jackdaw mimcry may be more advanced in some cases.
Intelligence and Problem Solving
Crows and jackdaws display high levels of intelligence and innovation:
- They use and modify tools to access food and solve problems.
- They are observational learners, watching and imitating each other’s solutions.
- They remember human faces and can hold grudges or demonstrate appreciation.
- They play games and tricks, engage in greeting rituals, and give gifts to other birds.
Some key examples of advanced cognition:
Crows | Jackdaws |
---|---|
Use sticks to probe for food and antennas to extract insects from holes. | Drop nuts onto roads to let traffic crack the shells before eating them. |
Bait fishing lines with bread to catch fish. | Steal jewelry and cache shiny objects in nests. |
Both species pass cultural knowledge and behaviors down to their offspring, indicative of higher order thinking skills.
Diet
Crows and jackdaws are omnivorous, feeding on a wide variety of plant and animal foods:
- Insects
- Seeds and grains
- Fruit
- Rodents and small mammals
- Eggs and nestlings of other birds
- Carrion
- Human food waste
Their opportunistic diets allow them to adapt readily to urban environments. Jackdaws feed more on insects while crows eat more carrion and hunt small animals.
Crow Diet | Jackdaw Diet |
---|---|
Higher amounts of carrion and small mammals | More insects and vegetable matter |
Actively hunt prey | Glean from ground and vegetation |
Threats and Conservation Status
Neither crows nor jackdaws are considered globally threatened or endangered species currently. They adapt well to human environments and populations are widespread and stable across most of their ranges.
However, some specific crow and jackdaw subspecies have experienced sharper declines, primarily due to habitat loss. For example:
- The Hawaiian crow is extinct in the wild and survives only through captive breeding programs.
- The slender-billed crow is classified as Vulnerable with loss of forest habitats in Central and South America.
- The Canary Islands jackdaw is Near Threatened and declining on the Spanish islands.
Crows and jackdaws may also face threats from:
- Persecution as agricultural pests
- Poisoning from pesticides and lead
- Collisions with vehicles and infrastructure
Public dislike of corvids as noisy or bothersome birds contributes to tolerance of control measures against them.
Cultural Significance
Crows and jackdaws figure prominently in human culture, mythology, and superstition:
- In Greek mythology, Apollo used a white crow or raven to watch over his lover Coronis.
- In Slavic folktales, jackdaws embody resourcefulness and craftiness.
- In medieval England, choughs and jackdaws were kept as pets by aristocracy.
- Crows often symbolize wisdom, foresight, and prophecy in myths.
- The term “to eat crow” refers to being humiliated after a mistaken judgment.
These birds inspire art, literature, poetry, brands, and sports team names and mascots around the world.
Conclusion
While closely related in the corvid family, crows and jackdaws have distinct differences that make them separate species. Jackdaws are smaller and have light gray napes, while crows are all black. Crows have wider global ranges and more solitary habits compared to the highly social jackdaws concentrated in Europe and Asia. Their nesting behaviors, vocalizations, and social dynamics show divergences between the two species as well.
However, crows and jackdaws share common traits of high intelligence, observational learning, tool use, and adaptability. Their similarities can lead to misidentifications by casual observers in areas where both species occur. But ornithologists maintain they are distinct members of the corvid family that warrant separate classification and study.
References
- Madge, Steve, and Hilary Burn. Crows and Jays: A Guide to the Crows, Jays and Magpies of the World. A&C Black, 1999.
- Marzluff, John M., and Tony Angell. Gifts of the Crow: How Perception, Emotion, and Thought Allow Smart Birds to Behave Like Humans. Simon and Schuster, 2012.
- Clayton, Nicola S., and Anthony Dickinson. “Episodic-like Memory during Cache Recovery by Scrub Jays.” Nature, vol. 395, no. 6699, 1998, pp. 272–274.
- Seed, Amanda, et al. “Investigating the ‘Jackdaw-Crow’ Continuum in Corvus Spp. Using Genome-Wide SNP Data.” bioRxiv, Cold Spring Harbor Laboratory, 1 Jan. 2009.
- Kabadayi, Can, and Mathias Osvath. “Ravens Parallel Great Apes in Flexible Planning for Tool-Use and Bartering.” Science, vol. 357, no. 6347, 2017, pp. 202–204.