Rookery

This is rook country; a late Easter break has brought me to the undulating pasturelands and woodlots of Dorset, where the green of spring is a week or more in advance of that in Norfolk. The still bare trees that crowd the narrow lanes are topped with the nests of rooks, upturned cones of sticks collected from nearby or stolen from the unguarded nests of neighbouring pairs. Many nests, though, have rooks in attendance, dressed in funereal black and with bone white bills. These are splendid birds; their ragged loose-winged forms rise effortlessly from the trees in the brisk wind, sweeping away to feed on the slowly warming turf. Others attend to unfortunate creatures that have been killed by traffic, scavenging much-needed protein from road-kill badgers and rabbits. A closer view in the strengthening sunshine reveals a plumage that is not simply black, but is instead dressed with a wonderful mix of bronze, blues and purples, reminiscent of the way in which oil on water separates out into a kaleidoscope of colours.

It is the social cohesion of the rookery that, to me, provides a real sense of the vitality of spring, more so than the sight of newborn lambs or a woodland alive with the sound of the first chiffchaffs. The sound of a rookery at dawn is something else, providing a bustling sense of the activity that is taking place within this vibrant community. Yet, most English rookeries contain fewer than 50 nests and only a handful have been recorded with more than three hundred nests. A few really big rookeries have been recorded in the past, notably on large Scottish estates where, for example, some 2,274 nests were noted at the Haddo House rookery near Aberdeen in the 1970s. The trend, certainly within England, seems to be towards smaller and smaller rookeries, perhaps a reflection of food availability, loss of suitable nesting trees or increased levels of disturbance.

Levels of activity vary throughout the day and, indeed, also change as the breeding season progresses. During the period of nest construction, raiding parties, composed primarily of young birds, attempt to steal twigs from unguarded nests. For this reason, breeding females will typically guard the nest while their mate seeks out suitable twigs. Only when the lining of the nest begins, is the female confident enough to join the male in collecting material. Once the nest is complete the female will initiate egg-laying, typically producing between two and six eggs which she will then incubate alone over the coming weeks. As the season progresses, so the expanding leaf cover hides the rookery from prying eyes, halting our glimpse on the busy collective lifestyle of these enigmatic birds.