Bird Families

Barnacle Raven

Pin
Send
Share
Send
Send


Ravens (Corvus) Is a genus of widespread birds of the Vranov family, the suborder of the Songbirds, the order of the Passerines. It includes such famous birds as ravens, ravens, jackdaws and rooks and makes up 1/3 of all species of the family.

There are other birds with a similar name that do not belong to this genus: Shrub crow (Zavattariornis stresemanni), genus Horned crows (Bucorvus). They will be discussed in other articles.

Etymology of the name

According to one version, birds owe the appearance of this name to the predominant color of their plumage. In Slavic languages, the adjective blackderived from the stem crow, meant black suit. In Indo-European dialects, a related word meant "to burn", "to burn", "to burn", "to turn black." Another version speaks of the origin of the word from the onomatopoeia "work", which is also present in the name of the sparrow.

Photo by: TagaSanPedroAko, CC0

Where do the crows live?

Corvus originally evolved from Central Asia. From there they traveled to North America, Europe, Africa, Australia and some islands. There are 7 species of the raven genus in Russia. They were brought to North America during the colonization of the mainland by Europeans. Their number increased with the development of agriculture, as crows are partially anthropodependent birds. They often live in cities and villages next to humans. In winter, they gather in large flocks, in which there are up to 200 individuals, and seek food in landfills or near shopping centers. Only in South America and Antarctica there are no representatives of this genus.

Ravens are found from the tropics to the arctic. Most of the species live in southern latitudes. In the north of Eurasia and North America, only the common raven lives. Birds occupy a variety of habitats: swampy meadows, dense forests, highlands, deserts and cultural landscapes.

Photo by: Neo, Mr. Anderson, CC BY-SA 4.0

Ravens lifestyle in the wild

Ravens are diurnal. They begin to fly before dawn. Until noon, the animals are actively looking for food, guarding mice at their holes, ravaging bird nests, and collecting scraps from garbage dumps. By noon, they gather in the trees to rest and exchange "impressions." Then they hunt and eat again. They spend the night in trees in parks and gardens, often forming large clusters.

After departure and separation from their parents, young birds first keep solitary. In October, they gather in flocks and begin to memorize each other's voices. For this, a "roll call" takes place in the group, then one bird screams, while the others are silent and remember its voice.

Photo by: Masa Sakano, CC BY-SA 2.0

All ravens know and are able to distinguish each other, they have a hierarchical division. The presence of high intelligence in these birds is evidenced by their ability to play. For example, the favorite game of crows is "baton with a baton": one bird jumps, holding a branch in its beak, the other catches up with it and picks up the object, taking the baton. At the same time, the first bird does not offer resistance, but immediately rushes in pursuit of the second. Ravens "dance", throw pebbles, pretend to be wounded to tease dogs, and do many other things that are not directly necessary for survival. Collectively, they take food from dogs and cats. One bird grabs the mammal by the tail, while the other takes the tidbits away at this time. In a pair, they steal eggs from birds, then one drives the hen from the nest, and the other drags the eggs.

Representatives of the genus are sedentary, wintering, less often nomadic or migratory birds. They adapt well to changes in external conditions. Common ravens are mostly sedentary, the hooded crow migrates south of the main range, the rook flies to winter in warm areas. In the temperate zone, the latter is present at all seasons, but these are different populations. In winter, flocks arrive here from the northern territories, and individuals nesting here in summer migrate to lower latitudes.

Photo by: Estormiz, CC0

What do crows eat?

Ravens are omnivorous birds, and their diet is very diverse. They eat almost anything, including other birds, molluscs, crabs, earthworms, small mammals, and amphibians up to hares and frogs. They eat carrion, nuts, fruits, eggs, seeds of cereals, conifers, field grasses (bird buckwheat, field bindweed). Fish crows pick up fish, crabs and shrimps discarded or lost by fishermen from the coast. The largest species of the genus mostly eat carrion, often kill wounded animals, and can even kill weak lambs.

The New Zealand crow hunts from under the bark of beetle larvae with the help of a tree branch, previously chopped off and cleaned of excess bark. He not only uses the tool, but also transforms it. Many birds feed on insect larvae from the back of cattle.

The hooded crow has a habit of storing excess food in reserve. She hides them in flower pots, in water pipes, in loose earth under bushes.

Rooks are mainly insectivorous birds. They also eat vegetable feed.

Photo by: GerifalteDelSabana, CC BY-SA 4.0

Types of ravens, names and photos

Below is a description of several species of birds from the genus Corvus.

  • Corvus corone (Linnaeus, 1758) - Black crow

It is a black bird with a metallic and purple sheen on the upper body. The body length of adult females is 50-54 cm, of males - 54.5-56.5 cm. The wingspan is 97-105 cm, wing length is 31-37.5 cm, weight is 600-690 g. The black crow is often confused with the rook. The crow's beak is thicker, but short, and the nostrils are covered with feathers. And she screams louder than a rook, clearly pronouncing the sound "r".

The black crow lives in Central and Western Europe, East and Central Asia, North Africa and North America. In Russia, it is found mostly in Eastern Siberia and the Far East. It settles on the edges of forests, in parks and gardens, in thickets of river valleys, in groves, less often on the slopes of coastal cliffs and on rocks.

Photo Credit: Judy Gallagher, CC BY 2.0

  • Corvus corone cornix, Corvus cornix (Linnaeus, 1758) -Graycrow

It is a subspecies of black, although some classifications distinguish it as an independent species. It is an ash-gray bird with black feathers on its tail, head (hood), throat, goiter (shirt-front) and wings. On the tail and wings, a feather with a metallic sheen. The bird's beak and legs are black. Juveniles are distinguished by the presence of a brownish tint in the gray coloration and the general softness of the feather.

The tail is rounded, in flight it opens like a fan. Wing length 30.5-34 cm, span about 1 m, body excluding tail 48-52 cm long, tail 17.5-18.5 cm, average weight 510 g. Beak 4-5 cm long is slightly curved along skate. In adult birds the eyes are dark brown, in juveniles it is dull-bluish. The crow flies slowly and hard, at a speed of 50 km / h. The bird's voice is well recognizable - it is a loud "kraa" or "carr".

The hooded crow lives in Western and Central Asia, in Northern, Eastern and Western Europe (Ireland, Scotland, Scandinavia, Poland, Hungary, Germany, Italy, Great Britain, Denmark). In Russia, she lives in the European part everywhere, except for the tundra, and in Western Siberia up to Lake Baikal. Leads a sedentary and nomadic lifestyle. Northern species migrate to the south for the winter. It inhabits river valleys, the outskirts of forests of various types, human settlements. In winter he settles in villages and towns.

Photo by: Marta Boroń, CC BY 2.0

  • Corvus corax (Linnaeus, 1758) -Raven, or common raven

Completely black raven, with a bluish or lilac metallic sheen on the upper side of the body and greenish on the underside. A bird with a massive beak and elongated neck feathers - "beard". This is the largest representative of the genus, its weight reaches 1-1.6 kg, body length varies from 60 to 70 cm, wingspan 120-150 cm. The eyes are dark brown. It differs from the black crow in its massive beak, dense build, and sedentary lifestyle.

The raven lives on the continents of Eurasia and North America, lives in North Africa, Greenland, Iceland. It is easier to name the regions and parts of the continents of the Northern Hemisphere where he does not live: in Taimyr, Yamal, the islands of the Arctic Ocean, in the deserts of Kazakhstan and Central Asia, in the central and eastern states of the United States, rare in Western and Central Europe.

Near the northern limits of their distribution, crows nest on rock ledges, usually on cliffs along the banks of rivers or the sea, in canyons of small streams, and in flat areas - on bushes and trees.

These birds feed on rodents, chase young and weakened hares, ravage bird nests, fish in shallow water bodies, peck at various berries. But the preference is given to the fallen.

Photo by: Frank Schulenburg, CC BY-SA 4.0

  • Corvus tristis Lesson & Garnot, 1827 - Hooded Raven

It differs from the black crow and the giant crow in relatively long tail feathers and short legs. The size is comparable to the black crow. Among the black plumage of an adult bird, white blotches on the tail and wings can be found. Juveniles have a gray body, pink beak and legs.

The habitat of the hooded crow is New Guinea and small nearby islands. It occupies forests of all types, rises in the mountains up to 1350 m above sea level.

Taken from the site: www.enciclopedino.it, CC BY-SA 3.0

  • Corvus frugilegus Linnaeus, 1758 - Rook

A bird with black shiny plumage. At the base of the beak of adults there is a patch of light skin, devoid of a feather. Unlike crows, rooks are more slender, they have pointed long wings and a sharp beak, the eyes are dark brown, and their legs are black. Rook wing length 28-34 cm, span 80-100 cm, beak length 5.4-6.3 cm, body length 45-47 cm, weight 300-500 g. Rooks are omnivorous, but mostly feed on worms, insects and their larvae.

The common rook is widespread in Europe, with the exception of the Far North, where it also sometimes flies. There is it in the south of Siberia and the Far East of Russia, in Central Asia and in the north of Egypt. In the northern regions it is a migratory bird; it winters in Great Britain, southern Europe, the Caucasus, in Minor, Central, East and Southeast Asia. In the southern regions of its range, the rook is sedentary. Inhabits the outskirts of deciduous and mixed forests, forest belts, groves near human habitation, in the mountains it occurs up to an altitude of 1600 m.

Photo Credit: Andreas Trepte, CC BY-SA 2.5

  • Corvus typicus (Bonaparte, 1853) - Sulawesian Raven

Body length is 35-40 cm, weight 175 g. The tail of the bird is short, the beak is thin, the plumage is black and white. The underside of the body and the ring on the neck are white, the rest of the body, legs and beak are black.

This species is endemic to the islands of Sulawesi, Muna and Butung from the Sunda Archipelago. The raven lives in high-mountainous tropical forests up to 1600 m above sea level, in lowlands and on hills.

Photo by: Kama Jaya Shagir, All rights reserved

  • Corvus caurinus (Baird, 1858)

The smallest crow with a body length of 33 to 41 cm, with relatively short legs and a thin beak. The plumage of the bird is black with a metallic sheen, the beak and legs are black. From the American crow (Corvus brachyrhynchos) the species differs only in size, so only a specialist can distinguish between birds.

It lives in the northwest of North America, Canada and the USA. Lives off the coast of Alaska, Washington State in the United States and British Columbia in Canada. Inhabits nearby islands as well. It feeds on insects, their larvae, as well as plants, such as figs.

Photo by: Ianaré Sévi, CC BY-SA 3.0

  • Corvus ossifragus Wilson, 1812 - Fish Raven

Outwardly, we hardly distinguish it from the American crow, except in the elongated feathers of the neck and thighs or in the softer and silky plumage. The truth is a little smaller in size. The length of its body is 36-41 cm. The upper side with a blue-green sheen, the lower side with a more green metallic shade. The eyes are dark brown.

It is found in the east and south of the United States, settling along the coast of the oceans, on the banks of rivers, lakes, and swamps.

The fish crow is omnivorous, but prefers crabs, shrimps, fish, eggs and chicks, nuts and grains, scraps of human food.

Photo by: Katka Nemčoková, CC BY-SA 3.0

  • Corvus monedula Linnaeus, 1858 - Jackdaw

Some classifications classify this bird as a separate genus. Coloeus... The datazone.birdlife.org database (dated 01/10/2019) classifies the bird as a raven (Corvus).

The bird is smaller than crows in size, with dense plumage and a short beak. The length of its body, taking into account the tail, is 34-39 cm, the wingspan is 65-74 cm, the weight is 136-265 g. The wings, tail and top of the head of the jackdaw are black with a blue or purple tint. The rest of its plumage is slate gray.

Jackdaws spend their nesting period in Europe, North Africa and Western Asia. In Russia, the border of their distribution coincides with the southern outskirts of the taiga. They hibernate in Central Asia, Southern Europe and North Africa. Some populations are sedentary.

Photo by: MatthiasKabel, CC BY-SA 3.0

Raven bird hybrids

Many taxonomists attribute the gray and black crows to the same species, but to different geographical races or subspecies. The emergence of viable hybrids also testifies in favor of their close relationship. Later, scientists found differences between them in the set of genes in the composition of one chromosome, so some classifications define these birds as 2 different species.

Birds born when these varieties of crows are crossed do not differ in life expectancy from their parents, but in general their viability is somewhat reduced. Their color is dominated by black, gray feathers form a collar of various configurations and sizes or a gray back with black streaks. The abdomen is often gray.

Hooded crows and ravens also have offspring, but their hybrids are not capable of reproduction. They are dark gray in color with a black head, wings and tail.

Crow's nests in the trees. Photo by: Dominicus Johannes Bergsma, CC BY-SA 4.0

What is the difference between a black raven and an ordinary raven?

These absolutely black birds are difficult to distinguish at first glance. But a closer look reveals that:

  • a raven's beak is thicker than a raven's,
  • crows are generally larger, their body length reaches 60-70 cm, while the body of crows does not exceed 50 cm,
  • in old ravens, the feathers of the goiter are characteristically bristling,
  • ravens rarely gather in groups, they prefer solitude or life as a couple, while ravens gather in flocks,
  • the raven "speaks in the nose", pronouncing sounds reminiscent of the combination "ka", can click, the raven makes guttural cries of "ka" or "kra".

Left black crow, photo: Dan Davison, CC BY 2.0. On the right is a common crow, photo: Diliff, CC BY-SA 3.0

Differences between a rook and a crow

  • The raven's beak is black and thick, in the rook it is thinner, its base is light, and there is no plumage around the beak.
  • The rook is less massive, its weight is 300-500 g, the raven weighs up to 1.5 kg.
  • In flight, it can be seen that the raven's tail is wedge-shaped, and that of the rook - with a straight edge.
  • The wings of the raven are pointed, the rook has straight.
  • The crow moves on the ground with wide strides, but never jumps, as the rook often does.
  • Ravens prefer to eat carrion, rooks - insects and seeds.

Rook on the left, photo: nottsexminer, CC BY-SA 2.0. On the right is a common crow, photo: Wolfgang Krause, CC BY-SA 3.0

Raven breeding

Males reach sexual maturity at the age of 5 years, females become sexually mature by living up to 3 years. Their breeding season begins at the end of winter. At this time, male crows show a class of "aerobatics", they make sharp turns in flight, take off vertically upward and turn over in the air. During courtship, partners show each other feathers on their throats.

Ravens often pair up for a long time or for a lifetime, and the juveniles left with their parents since last year help them guard the nests and feed the chicks. Birds build nests on treetops, rocks, human buildings, and power line poles. They are made from dry branches held together by pieces of bark, grass, wire and lined with feathers, wool or rags. Both the male and the female are involved in the construction. The building has been used by a couple for several years in a row. Sometimes representatives of the genus can settle in the nests of birds of prey. They lay eggs not only in the nests, but also in the hollows of trees, under the roofs of houses, in holes, in crevices of rocks.

Photo by: Vijayanrajapuram, CC BY-SA 4.0

The nesting period of ravens lasts from 30 to 40 days. Birds lay 3 to 9 greenish-blue eggs with brown specks.

Egg weight is 19 g, length 42 mm, diameter 29 mm. When the first clutch is lost, the birds lay the second. The female incubates eggs for 19-22 days.The male feeds her.

Photo by: nottsexminer, CC BY-SA 2.0

The hatched crows live in the nest for 6-10 weeks. Mother and father feed them reptiles, molluscs, rodents, insects, worms, carrion, eggs and chicks of other birds, ruthlessly destroying nests and birdhouses.

After departure, they remain under the care of their parents for a long time.

Photo by: Reju.kaipreth, CC BY-SA 3.0

Ravens know how to defend their nests. All neighboring birds fly to the cry of the attacked pair. Falcons often settle next to them and in old crow's nests. This neighborhood also saves their offspring. Falcons also do not remain in debt: having heard the warning cry of crows, they attack swamp harriers, buzzards and other predators.

Photo by: nottsexminer, CC BY-SA 2.0

The chick in the photo is only 10 days old. Photo by: Bugaga, Public Domain

How many years do crows live?

In nature, crows live up to 15-20 years, jackdaw up to 7.3 years. In captivity, life expectancy reaches 40-70 years.

Enemies in nature

The Hooded Crow is a secondary host for nesting parasites such as the Great Spotted Cuckoo and the European Magpie. At the same time, the crows' own offspring suffers. In addition, the worst enemy of individuals of the genus Corvus is the owl, it attacks birds at night. Crows are vindictive and take revenge on their abuser for a long time.

Also, representatives of the genus are hunted by golden eagles, goshawks, white-tailed eagles, peregrine falcons.

Ravens accompany large predators (bears, foxes, arctic foxes, wolves) in the hope of getting hold of the remnants of prey and at the same time fall into their paws.

Photo by: Yellowstone National Park, Public Domain

Ravens harm

With a large concentration on one territory and with a lack of food, the hooded crow ruins the nests of waders, ducks and many other openly nesting birds. But for the most part, the remains of sparrow and pigeon eggs are found in her stomach.

The invasion of a flock of crows in vegetable gardens and orchards does not bode well either. In cities, birds carry scraps from landfills, make noise and pollute monuments with droppings.

The claim that crows spread the disease is false. And this is precisely what the crohunters (fans of shooting birds) justify their cruelty. Crows are scavengers, and their stomachs contain a large amount of concentrated acid that kills pathogenic microflora. Their high body temperature and ability to resist infections make them very clean animals. And by eating dead carcasses of birds and rodents, they, on the contrary, destroy the infection, cleansing human settlements.

Photo by: PJeganathan, CC BY-SA 4.0

The benefits of ravens

Falcons, merlins, kestrels, long-eared owls often live in old nests of crows. Hooded crow is the main supplier of nests for these birds.

Ravens, feeding on carrion, are nursery birds. In places where cereals are grown, they destroy rodents. Their role is also significant in the regulation of the number of insects. For example, the hooded crow pecks many larvae of the oak leafworm, the May beetle, because its nutrition is 60 or 70% of insects. Rooks also eat harmful insects: grass beetles, poisonous scoops, weevils, turtle bugs, meadow moth caterpillars.

Ravens love to stock up. When storing plant seeds, they hide them in different crevices, pits, and often forget about it. And the seeds germinate and give rise to new phytocenoses. It turns out that the distribution of pines and oaks is largely due to crows and jays.

Photo by: Rajatsharma10695, CC BY-SA 4.0

Keeping a crow at home

Hooded and black crows, as well as common crows, especially when taken when young, are easy to tame. They are very smart, but restless, thieving and noisy birds. If the owner has the patience, they can be taught to speak and made tame. The talking raven attracts with its exoticism. But how to keep such a bird next to you?

A domestic crow should live in a spacious aviary or perch, fixed with a chain. In any case, he needs to be given time every day for flying and moving around the house. He must "walk" for at least 1.5 hours. The bird needs to be bathed 1 time in 2 days, and also taken out into the sun.

You can feed a bird in captivity:

  • raw chicken and beef,
  • boiled chicken
  • quails,
  • mice,
  • day-old chicks,
  • rabbits,
  • cereals (buckwheat and oatmeal),
  • low-fat cottage cheese,
  • carrots,
  • berries
  • apples,
  • boiled chicken eggs,
  • dry dog ​​food (but not more than 1/3 of the total diet).

  • pork meat
  • salty foods
  • tomatoes,
  • potatoes,
  • citrus fruits,
  • black bread
  • milk.
back to content ↑

Pin
Send
Share
Send
Send