What do they look like?
Common ravens are large, black birds with a wedge-shaped tail. They have long feathers on their throats, which are called 'hackles'. Common ravens are the largest species of perching birds (passerines). Adults reach up to 69 cm in length and from 689 to 1625 grams in weight. They can be distinguished from other crow and raven species by their large size, more wedge-shaped tail, thick bill, a tendency to soar and glide, rather than flap their wings (as in crows), and their harsh, croaking calls. The sexes are generally alike, although females may be smaller. (Boarman and Heinrich, 1999)
- Other Physical Features
- endothermic
- hom*oiothermic
- bilateral symmetry
- Sexual Dimorphism
- sexes alike
-
- Range mass
- 689 to 1625 g
- 24.28 to 57.27 oz
-
- Range length
- 69 (high) cm
- 27.17 (high) in
-
- Average basal metabolic rate
- 5.5656 W
- AnAge
Where do they live?
Common ravens are are one of the most widespread, naturally occurring birds worldwide. They are found throughout most of North America, into Central America, Europe, Asia, and northern Africa. They are native to the Nearctic and Palearctic regions.
- Biogeographic Regions
- nearctic
- native
- palearctic
- native
- oriental
- native
- neotropical
- native
- Other Geographic Terms
- holarctic
What kind of habitat do they need?
Common ravens prefer open landscapes, such as treeless tundra, seacoasts, open riverbanks, rocky cliffs, mountain forests, plains, deserts, and scrubby woodlands. However, these ravens can be found in most types of habitats except for rainforests. Common ravens in North America tend to be found in wild areas, whereas their cousins, common crows tend to be found more in cities and suburbs. (Boarman and Heinrich, 1999)
Common ravens generally roost on cliff ledges or in large trees but have also established nests on power-lines, in urban areas, and on billboards, to name only a few. (Boarman and Heinrich, 1999)
- These animals are found in the following types of habitat
- temperate
- terrestrial
- Terrestrial Biomes
- tundra
- taiga
- desert or dune
- savanna or grassland
- chaparral
- forest
- scrub forest
- mountains
How do they reproduce?
Common ravens spend a lot of time doing various kinds of displays towards each other, some of these may be courtship displays. They probably find mates during the fall or winter of their first year and stay together for at least a few years and perhaps for life. (Boarman and Heinrich, 1999)
- Mating System
- monogamous
Common ravens lay their eggs and begin incubating them between mid-February and late May, depending on the length of the winter. Usually 3 to 7 eggs are laid per nest and incubated for 20 to 25 days. The young leave the nest at 5 to 7 weeks old. After leaving the nest they often stay around their parents for longer, being fed and learning more about their environment. (Boarman and Heinrich, 1999)
- Key Reproductive Features
- iteroparous
- seasonal breeding
- gonochoric/gonochoristic/dioecious (sexes separate)
- sexual
- fertilization
- internal
- oviparous
-
- How often does reproduction occur?
- Common ravens breed once yearly.
-
- Breeding season
- Breeding occurs in lmid-February through May.
-
- Range eggs per season
- 3 to 7
-
- Average eggs per season
- 5
- AnAge
-
- Range time to hatching
- 20 to 25 days
-
- Range time to independence
- 5 to 7 weeks
-
- Average age at sexual or reproductive maturity (female)
- 3 years
-
- Average age at sexual or reproductive maturity (female)
Sex: female - 1095 days
- AnAge
- Average age at sexual or reproductive maturity (female)
-
- Average age at sexual or reproductive maturity (male)
- 3 years
-
- Average age at sexual or reproductive maturity (male)
Sex: male - 1095 days
- AnAge
- Average age at sexual or reproductive maturity (male)
Females incubate the eggs but both parents care for the young once they have hatched.
- Parental Investment
- altricial
- male parental care
- female parental care
How long do they live?
A wild raven was recorded living for 13 years and 4 months. Captive birds may live much longer, captives at the Tower of London in England live for 44 years or more. Probably most common ravens die during their first few years of life. (Boarman and Heinrich, 1999)
-
- Range lifespan
Status: wild - 13 (high) years
- Range lifespan
-
- Range lifespan
Status: captivity - >44 (high) years
- Range lifespan
-
- Average lifespan
Status: wild - 206 months
- Bird Banding Laboratory
- Average lifespan
How do they behave?
Common ravens are known for their intelligence and complex social behaviors. They seem capable of learning innovative solutions to newly encountered problems. Common ravens often feed in larger groups where food is plentiful, and young birds may roam together and sleep in common night roosts, but most ravens live alone or in male and female pairs. These mated pairs establish territories and keep other ravens out of them. Common ravens don't migrate, but they may travel shorter distances to avoid extreme weather. (Boarman and Heinrich, 1999)
Common ravens walk on the ground or fly. They may also glide and soar, which they do more often than American crows. (Boarman and Heinrich, 1999)
- Key Behaviors
- flies
- glides
- motile
- sedentary
- solitary
- territorial
-
- Range territory size
- 5.1 to 40.5 km^2
How do they communicate with each other?
Common ravens make many different kinds of calls for communication. They often seem to be speaking or mimicing the sounds of other animals because they are capable of making so many different kinds of sounds. They also make alarm calls, advertise their territories by calling, and make comforting sounds. They also use physical displays to either threaten or appease other ravens. (Boarman and Heinrich, 1999)
- Communication Channels
- visual
- tactile
- acoustic
- Perception Channels
- visual
- tactile
- acoustic
- chemical
What do they eat?
Common ravens are omnivorous. They eat a wide array of animal foods, including insects, spiders, amphibians, small mammals, birds, reptiles, and carrion. They are attracted to carrion and eat also the insects that feed on carrion (chiefly on maggots and beetles). They are also known to eat the afterbirth of ewes and other large mammals. Vegetable foods include grains, acorns, fruits, and buds. By looking at raven stomach contents, researchers have shown that the most important food source for common ravens is mammal flesh, probably in the form of carrion. Insects and birds are also important food sources. Common ravens take their food from the ground and will store foods of all kinds, including nuts, bones, eggs, and meat. As soon as young ravens leave the nest they begin experimenting with hiding foods in storage areas. (Boarman and Heinrich, 1999)
- Primary Diet
- carnivore
- scavenger
- Animal Foods
- birds
- mammals
- amphibians
- reptiles
- eggs
- carrion
- insects
- terrestrial non-insect arthropods
- Plant Foods
- seeds, grains, and nuts
- fruit
- Foraging Behavior
- stores or caches food
What eats them and how do they avoid being eaten?
Common ravens are not often preyed on, even as eggs or young in the nest. Predators on nestlings may include large birds of prey, other ravens, owls, and martens. Golden eagles, great horned owls, and coyotes have been observed attacking nests and fledglings. Adults are usually successful at defending their young and will chase predators away. Common ravens are careful at foraging areas and will only approach new types of carrion or new situations after reassuring themselves that no predator is nearby. (Boarman and Heinrich, 1999)
-
- Known Predators
-
- birds of prey
- owls
- martens
- golden eagles
- great horned owls
- coyotes
What roles do they have in the ecosystem?
Common ravens help to recycle nutrients into the ecosystem by eating the carcasses of dead animals. They are also important predators.
Do they cause problems?
Common ravens sometimes eat crops such as grains, nuts, and fruits, and have been accused of killing or maiming small livestock. They may also negatively affect conservation efforts aimed at desert tortoises, sandhill cranes, and California condors. (Boarman and Heinrich, 1999)
- Ways that these animals might be a problem for humans
- crop pest
How do they interact with us?
Common ravens eat carrion, which helps by removing the carcasses of dead animals that may carry diseases.
Are they endangered?
Common ravens no longer occur in some parts of their range because they have been shot and poisoned. There are some local programs to control raven populations where they are considered dangerous to endangered species such as desert tortoises and sandhill cranes. However, common ravens may be re-establishing populations in some parts of their range and continue to do well in other parts of their range. (Boarman and Heinrich, 1999)
-
- IUCN Red List
- Least Concern
More information
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- US Migratory Bird Act
- Protected
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- US Federal List
- No special status
-
- CITES
- No special status
Some more information...
Common ravens are very important in native cultures throughout their range. Raven is a common and important mythic creature in western Native American traditions. (Boarman and Heinrich, 1999)
References
Chandler, Robbins, Bruun, Zim, Golden, A GUIDE TO BIRDS OF NORTH AMERICA, Golden & Press, New York, 1966. (pgs 212-213)
Goodwin, CROWS OF THE WORLD, 2nd Edition, British Museum, 1986. (pgs. 124-130)
Terres, John K, THE AUDOBON SOCIETY ENCYCLOPEDIA OF NORTH AMERICAN BIRDS,
Boarman, W., B. Heinrich. 1999. Corvus corax: Common Raven. The Birds of North America, 476: 1-32.
