We asked BTO Garden BirdWatch participants to keep a record of the different types of Rook behaviour that they witnessed in their gardens, grouped according to whether the behaviour related to:

• feeding,
• caching food,
• tolerance of other individuals,
• playing with an object,
• social interactions,
• vocalisation.

A total of 91 people recorded at least one behavioural act during the recording period from across the country, though 43 commented on behaviour seen outside of the recording period. Of the behaviours recorded, feeding was the most common, followed by tolerance behaviour and vocalisations.

Feeding and object play

Unsurprisingly, 92% of people who recorded behaviour saw Rooks feeding in their gardens. While the Rooks were not fussy, eating anything from seeds to ‘Flutter Butter’, a couple of observers were surprised to see them take young birds or even mice. Four participants observed Rooks coming into their gardens for walnuts, which anecdotally seem to be popular amongst corvids. 

Almost 40% of observed feeding behaviour involved manipulation of feeders. A few Rooks seemed adept at pulling food up on strings, but most preferred to remove the feeders from where they were hanging to drop them onto the ground. It was interesting to see an element of cooperation, though not surprising as Rooks have strong social bonds. One participant saw a bird pushing the feeder towards another Rook so that it could catch and feed from it. Several people saw individual birds emptying feeders so that others could feed on the ground below. 

Of the birds that were manipulating feeders, only 15% were juveniles, suggesting that these were birds that had learned these behaviours before. Manipulation of feeders is very similar to object play behaviour, but sadly little of the latter behaviour was seen. One participant, however, did observe a Rook picking a stick up, dropping it, hopping away and repeating this behaviour which must have been for fun.

Caching food

While quite a few participants saw Rooks flying off with food, only 5% actually saw them bury it. It does make sense, however, for a bird to bury food away from prying eyes. Most Rooks that were observed caching were adults and took peanuts or bread. Many of the birds that watched to see where the food was cached were juveniles, presumably learning about what to do in the future.

Tolerance behaviour

64% of participants observed Rooks displaying tolerance behaviour towards other species and only 35% of cases involved intolerance, suggesting Rooks are more than happy feed alongside other birds. Of the birds that were not tolerated, Jackdaws and pigeons were at the top of the list potentially due to being greater competition than smaller birds.

Vocalisation and social behaviour

According to anecdotal comments from participants, juvenile Rooks seemed to have a much more limited vocabulary than the adults and were often only vocal when begging. While many people heard Rooks generally cawing, almost a quarter saw them doing so with display behaviour. Many also commented on how adults would fly into nearby trees and advertise that food was being put out and one person even heard a Rook ‘sing’ which is very rare. They described it as involving caws, clicks, pops and chattering without a break.

Other than vocalising, the other social behaviour observed most was Rooks feeding each other. While much of this was early in the recording period, with adults feeding juveniles, some people did see it as part of pair-bond behaviour. Some people also saw pairs displaying together and grooming each other. 

The results of this observational study were summarised in an article in our quarterly magazine Bird Table.