Avian Cooperation: Rooks Work Together to Solve Puzzle for Food

Nests are built high in the trees and made of twigs and branches. These are broken off trees or stolen from a nearby nest. Some rookeries can contain thousands of birds, with their noisy calls making them easy to discover. Worms, beetles and other invertebrates are the rook’s main food, which it catches by probing the ground with its large beak. It will also feed on grain, fruit, acorns and occasionally carrion and birds’ eggs. Rooks have all-black plumage, but an iridescent sheen is notable when seen up close.

Thanks to Clayton’s own eclectic tastes, which span consciousness to choreography (her other love, besides birds, is dance), the lab also engenders a curious synthesis of ideas drawn from both science and the arts. The rook (Corvus frugilegus) is a member of the family Corvidae in the passerine order of birds. It is found in the Palearctic, its range extending from Scandinavia and western Europe to eastern Siberia. It is a large, gregarious, black-feathered bird, distinguished from similar species by the whitish featherless area on the face. Rooks nest collectively in the tops of tall trees, often close to farms or villages, the groups of nests being known as rookeries.

An open letter signed by 358 academics from around the world has called on the university to reconsider. One signatory, Alex Thornton, a professor of cognitive evolution at Exeter University, said it would represent an act of “scientific vandalism and monumental self-sabotage”. Emery told me that creating something similar somewhere else would be pretty difficult, “if not impossible”, and incredibly expensive. “These birds cannot be purchased ‘off the shelf’,” he said. “If Nicky’s corvid lab closes down, then it couldn’t really start up again.” As the letter states, the lab at Madingley is the only one of its kind in the UK, and remains “globally unique in its size and capability”. “Magic reveals a lot about the blind spots we have,” says Clayton, and lately magic has opened up a new line of inquiry for the lab.

They are slightly smaller than crows, with a typical wingspan of 90cm. The species’ key identifying feature is the grey-white skin at the base of its long, pointed beak. This distinguishes it from the similar-looking carrion crow, which has an all-black beak. Chimpanzees, and possibly a few other primates, are the only other species that have proved themselves capable of the same task. Rooks are extremely social birds, living in colonies of hundreds of members, and are likely to have faced evolutionary pressure to learn to cooperate, Seed says. As news that the lab faces closure has rippled through the scientific community, the reaction has been of sadness and dismay.

Only this time the venue is the Comparative Cognition Laboratory in Madingley, Cambridge, and the ball is a waxworm. Leo – poised, pointy, determined – is perched on a wooden platform eager to place his bet. A wriggling morsel is laid under one of three cups, the cups shuffled. He snatches What do birds eat the waxworm in his beak and retreats to enjoy his prize. Aristotle, a fellow resident donned in a glossy black feather coat, who has been at the aviary almost as long as the lab itself, looks on knowingly. Rooks are communal breeders, nesting in colonies known as rookeries.

Their nests are solidly constructed of twigs and soil and are used year after year. The birds lay three to five light greenish, heavily speckled eggs, and the young are able to fly about a month after birth. Rooks dig for larvae and worms in meadows and plowed fields and may pull up grain seedlings and young potato plants. Rooks are mainly resident birds, but the northernmost populations may migrate southwards to avoid the harshest winter conditions. The birds form flocks in winter, often in the company of other Corvus species or jackdaws.

One of the big questions for her concerned “mental time travel” – the ability to remember the past or plan for the future. “People assumed this is something that only humans have,” she says. But, at Madingley, she observed that jays were also capable of thinking about the future.

They are good at problem-solving and memory puzzles and they can even use tools. Referring to animal species that have been transported to and established populations in regions outside of their natural range, usually through human action. Rooks are highly social, living and interacting in large groups, although mating tends to monogamous. This bird species is largely arboreal and actively defends its territory.

They return to their rookeries and breeding takes place in spring. They forage on arable land and pasture, probing the ground with their strong bills and feeding largely on grubs and soil-based invertebrates, but also consuming cereals and other plant material. Historically, farmers have accused the birds of damaging their crops, and have made efforts to drive them away or kill them. Like other corvids, they are intelligent birds with complex behavioural traits and an ability to solve simple problems. Watching alongside me is Professor Nicola Clayton, a psychologist who founded the lab 22 years ago, and we are joined by Francesca Cornero, 25, a PhD researcher (and occasional cups and balls technician).

Rook, (Corvus frugilegus), the most abundant Eurasian bird of the crow family Corvidae (q.v.). It resembles the carrion crow in size (45 cm [18 inches]) and in black coloration, but the adult rook usually has shaggy thigh feathers and has bare white skin at the base of its sharp bill. The species ranges discontinuously from England to Iran and Manchuria and is migratory. Rooks nest in large colonies (rookeries) in tall trees, sometimes within towns.

Every day, around 10.30 am, rooks would start to assemble on the roof above the kitchen. Then, as the coffee service finished, the servers would toss the unsold toast out of the window. Almost every day, an Australian raven drops a hard crust of bread in our birdbath.

Birds that had not previously stolen food for themselves remained blissfully ignorant. It seemed that jays could not only relate to a previous experience, but put themselves in the eyes of another bird and make decisions based on the possibility of future events. The results of the study were published in Nature in 2001. As large, noisy and social birds, rooks are easy to spot. Look for groups of black birds feeding in open fields and along roadsides.

But Rooks also form life-long partnerships, called pairbonds. Rook pairs spend a lot of time close together, feeding one another, displaying and vocalising together and preening. They also act at the same time, one copying the other’s movements. We wanted to know if Rooks were interacting in pairs and groups, and whether they were aggressive to each other.

We reserve the right to edit items for clarity and style. Please include a postal address, daytime telephone number and email address. A grassland with scattered trees or scattered clumps of trees, a type of community intermediate between grassland and forest. For example, light reflected off of water has waves vibrating horizontally. Some animals, such as bees, can detect which way light is polarized and use that information. Reproduction in which eggs are released by the female; development of offspring occurs outside the mother’s body.

The rooks in Seed’s lab, on the other hand, kept trying (and failing) to move the platform alone, even after successfully obtaining the food with a partner. Rooks and other corvids, such as crows and ravens, are extremely clever, with intellectual abilities on a par with those of chimpanzees. Animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Young are born in a relatively underdeveloped state; they are unable to feed or care for themselves or locomote independently for a period of time after birth/hatching.

In winter, keep your eyes peeled for flocks flying above woodland as they come in to roost. Scientists at the University of Cambridge tested the rooks, which are Eurasian members of the crow family, by placing dishes of food on a platform out of reach of a bird enclosure. A single string looped from the enclosure to the platform and back again. Moving the platform closer required pulling on both ends of the string simultaneously, a feat that is only possible if two birds work together, each tugging on one end.

Rooks like to play with different objects, including sticks and stones. Although they don’t use sticks as tools, they do play with them, as well as use them to build nests. We asked if Rooks were using objects, especially in unusual ways. Many years ago, at work, we had a mobile service with coffee and toast for sale. My ground-floor office looked out onto a grassy area, and the kitchen was opposite.

Scientific American is part of Springer Nature, which owns or has commercial relations with thousands of scientific publications (many of them can be found at /us). Scientific American maintains a strict policy of editorial independence in reporting developments in science to our readers. The rooks would swoop, grab a slice of toast, tear it into pieces and bury it.

It added that it would be “delighted” to work with an external funder to keep the aviaries open, should one emerge in the next few months. It is hard to put a precise figure on what it would cost to keep the lab open in the long run, but Clayton estimates it could cost £300,000 to £500,000 to secure the birds for another five or six years. She has received some partial offers from potential donors, though nothing has been confirmed. All corvids are noisy birds, who vocalize to tell others about the location and quality of food, the membership of a pairbond, warning about predators and possibly even their name. We wanted to know what vocalizations were occurring and whether they accompanied visual displays.

Soak up the wonder of wetlands at this sweeping riverbank reserve where wildfowl and wading birds flock to feed, rest and nest. Even as we reach the beginning of November, autumn migration is still very evident. Birds continue to arrive in the UK from more northerly regions to spend the next few months here in our warmer winters, before…

It comes back after 20 minutes or so to retrieve and eat it, once soft. I am sure the rook described in the question – a fellow corvid – is doing a similar thing. No doubt the moisture in the earth softens the bread too. Referring to an animal that lives in trees; tree-climbing.