Rook

By Dominic Couzens

Steve Young/Alamy

Steve Young/Alamy

Here’s some advice: never pick a hotel too close to an airport. I recently selected what seemed like the perfect spot near Gatwick, but the extraneous noise was remarkably persistent. It wasn’t just the air traffic in the sky and on the runway, the disturbance also came from excessive commotion and shouting in a construction site next door. You would think the hotel would have been properly sound-proofed, but the din, particularly the intermittent swell of raised voices, kept me awake from the crack of dawn. Trip Advisor (there are other such websites) has been alerted.

Mind you, none of this was human noise; the gentle, far-off rumble of Gatwick planes was incidental. All the sound – the taking off and landing, the construction and the shouting – was made by Rooks. The hotel was next to a colony in the midst of its early-season explosion of activity – and it was a glorious hubbub. And of course, truthfully, I relished the immersion into natural noise and have no complaints at all.

Many people are familiar with this wondrous countryside cacophony, a far cry from the sweetness of the dawn chorus, more heavy metal than easy listening, an offering of Rook rock. There are, apparently, more than 20 different Rook calls, but differentiating them is hard because many of them are variations of ‘caw’. Generally, Rook caws are gentler and less hostile than Carrion/Hooded Crow calls (a Rook is a crow that has had anger counselling); but after that, who can tell a ‘caw’ from a ‘caw’? Listen carefully for long enough and you will hear the odd higher-pitched offering, as if an adolescent’s voice was breaking, but the great delight in listening to a Rook colony is the overall sound that many voices make together. The dark birds bring life and verve. If you are stressed, I seriously suggest that you spend a few minutes next to a rookery in full breeding swing. Shut your eyes, breathe in the rural smells and allow the sound to wash over you. The racket is remarkably peaceful.

Nature Photographers Ltd/Alamy

Nature Photographers Ltd/Alamy

Another delicious aspect of rookery life is also, of course, its early start. Rooks are among the earliest of all British birds to breed, frequently bringing sticks to their nests in February, or even on a balmy January day. By the third week of March, anywhere in the UK, Rooks will have eggs. And before that, the birds build nests, display, copulate and make a great deal of noise. While the early spring countryside tentatively opens its eyes and yawns, and Primroses peep shyly from banks that aren’t yet used to the sun, Rooks are already partying.

The reason for the Rook’s fast start is that it needs to feed its young on invertebrates that are easier to find and harvest when the ground has not yet dried out. Rooks relish the swish and squelch of spring, when the ground is likely to be saturated from winter rains. Not only will the ground be soft, so that Rooks can plunge their bills into mud full of leatherjackets and earthworms, but it will also be comparatively bare, before too much growth overtakes the foraging areas and make it easier for prey to hide.

Their internal physiology does the arithmetic for them. If they lay eggs, say, on or about 15 March, they will hatch 16-18 days later, in the first week of April. As we all know, that is long before the sun takes hold and dries out the British countryside. An interesting quirk of breeding early is that Rooks need to work their relationships out early, too. You might be surprised to hear that this happens in autumn, when you’d think that birds’ minds are consumed with the coming winter. But no, with such a strict timetable, the nuptials are sorted before the leaves have fallen off the trees.

Judging by the behaviour of Rooks in their colonies in early spring, however, you could conclude that they don’t do a very effective job in the autumn. The rookery is a place of sexual licence, and this goes some way to explaining why, at certain times, the colonies make such a fearful racket. Despite having been paired off, both sexes are given to promiscuity. For example, it seems that a male Rook doesn’t pass muster unless it has copulated with every one of its nearest female neighbours. Several weeks in February and March see daily conflicts over inappropriate liaisons.

Vishnevskiy/Alamy

Vishnevskiy/Alamy

Part of the problem is the opportunity. Intensely colonial, Rooks place their nests, on average, 0.5m to 2m apart. There is no such place as a rookery nook, a private corner of the melee, because everybody can see everybody else.

If there is a particularly desirable member of the opposite sex in the nearest neighbourhood, there is scant chance to escape temptation. A randy male is going to know exactly when the irresistible female’s mate is not at home; it will also be aware that the female, which tends to remain on or close to the nest for long periods of the breeding season, including all incubation and most brooding, will frequently be home alone.

The result is rookery nookie, and not all of it is consensual. ‘Rape,’ or forced copulation, happens all the time. And every time it happens, there is an almighty outbreak of indignation. The nearby males leap to the ‘defence’ of the blighted female, voices at full volume in protest. Their aim, it seems, is to stop the outrage in its tracks, but their real motive may be different. Rooks have been seen to angrily break up an ‘attempted rape’, only to succumb to temptation with the same female themselves. It seems that the lofty, open cup-nests, situated close together, in treetops yet without leaves, promote open relationships. It has also been said that the female Rook’s soliciting posture is not very different from its posture when incubating, which cannot help.

The open nest arrangement is also a cue for some intriguing female behaviour. Somewhat surprisingly, given the above, many Rookeries hold a proportion of unpaired females. Such birds won’t have any problem becoming impregnated, of course, but they need a male to help them guard the nest and provide food when they are incubating.

In the absence of a mate, these females sometimes actually get round to building a nest, somewhat unsubtly, directly next to another bird’s nest, or even abutting it, presumably in the hope of siphoning off some of the male’s provision. It rarely ends well; typically, both the unpaired female’s nest and her immediate neighbour fail.

One of the great sights of spring is to watch the comings and goings of Rooks at a rookery. Throughout March, and into the second half of April, almost all of these comings and goings are commuting runs by males. With good nest sites at a premium (the higher they are up a tree, the fewer the losses of eggs and chicks), somebody needs to be present on a territory most of the time, so it becomes incumbent on the males to do all the provisioning.

For weeks they fly to and fro from feeding site to nest site, travelling ‘as the crow [actually the Rook] flies’, bringing in food. From the egg-laying stage to the point where the chicks are half grown, the male brings everything. And every time they arrive at the nest, there is a cacophony, an excuse for Rook rumpus.

Meeting, greeting, competing, complaining – the noises of Rooks are many and wondrous, reflecting the complexities of their lives.

Rook species factfile

Scientific name: Corvus frugilegus
Length: 44-46cm
Wingspan: 81-99cm
UK numbers: 1,100,000 breeding pairs
Habitat: Open field or along roadsides. Town parks and villages
Diet: Pretty much anything – seeds, insects, worms, small mammals as well as eggs and nestlings

Where to see Rook

Mostly seen in flocks in open fields or feeding along a roadside. Largely steer clear of the middle of big towns and cities, but will come into town parks and villages. They are absent from the far north-west of Scotland.