Water levels challenge the birds

The volume of water passing down the river over recent weeks has been staggering, requiring careful management of the sluices by Environment Agency staff. Such volumes underline the power of nature, the swollen waters swirling and deeply coloured with debris, and flowing with force. On some days the waters have slipped the confines of the river banks to flow out across the low lying meadows and on through the wood where I will search for blackbird nests come spring.

The conditions must prove challenging for the river’s inhabitants and I often wonder how the fish and otters fair when the river is in full spate. The rising waters will also have caught out some of our nesting birds. I have a suspicion that at least some of the local mallards will have been down on eggs, their early nesting prompted by the mild conditions witnessed earlier in the year. A few pairs nest in the alder carr alongside the river and any that had already started here this year will have been flooded out.

The water level by the old mill has crept up above the entrance to a small cavity in which the grey wagtails often nest. The fact that these delightful little birds start breeding somewhat later in the year means that they should be fine. Elsewhere, and well away from the lowland rivers of the brecks, many dippers will be beginning their breeding season, nesting in river bank cavities or on ledges under bridges. Some of these nest sites will almost certainly have been lost to the torrents of water rushing downstream, through river systems across the north and west of the country.

Away from the river and some of our other early nesters will have instead had to face a battering from the strong winds. Rooks and herons will already be at their nest sites, situated high in the canopies of trees, and their nests of stick may well have been dislodged. Repairs will be necessary, delaying the start of the breeding season. Of course, the weather also provides opportunities. The local crows have, for example, been feasting on insects and other prey pushed out of the meadow’s thick cover by rising waters. It would seem that there is resilience in nature.

In pursuit of spring

The other weekend, a series of meetings and a conference took me south through the Chilterns, west to Reading and beyond. Any journey south that is made at this time of the year has the lure of spring about it. Spring is more advanced on the south coast than here in East Anglia; the buds more strongly swollen and the spring flowers further into bloom. It feels as if you are passing through time, rather than space.

Driving through mixed arable land, I passed many a clump of trees that hosted a rookery, with birds in attendance and standing sentinel over nesting attempts that already well underway. Skirting further south I drove through Gilbert White’s Selborne, dominated by its beech hanger and the surrounding downs. On another day I would have stopped here, walked the zig-zag path up the hanger or tacked across the fields towards Noar Hill. There is a strong sense of history in this landscape, the feeling that it has not changed quite so much as to now be unrecognisable to its former inhabitants.

The poet and writer Edward Thomas made a not dissimilar journey almost exactly a century ago. Heading west out of London with his bicycle, Thomas set out ‘In Pursuit of Spring’ documenting the landscape, its people and its sense of place. Although sometimes portrayed as a piece of nature writing, Thomas’s book is, in reality, something rather different. The wildlife described in his account is not central to the text. Instead it is part of the backdrop, contributing to the sense of landscape and place, working its part alongside names marked on the gravestones of the churchyards visited or the character of the buildings that sit within the folds of countryside that are passed.

Thomas’s journey is also a personal one and through his words you can discover something of the man and his reactions to a landscape that was undergoing a period of change. There are passages where Thomas laments what has been lost, something that I suspect is common to most writers on landscape, but these are balanced by moments where the joy of being at one with the landscape pushes through strongly. Landscape has this amazing ability to take hold of us and to lift our spirits. For me the sight of these springtime rookeries is a case in point; they are so characteristic of spring in the south of England, reflecting the wider landscape within which they sit. To see such a rookery can transport me immediately back to my childhood, delivering me to a landscape that skirts the downs and which appears timeless in its associations. This remains the landscape of Edward Thomas and those writing before him.

A sense of spring

It is the spring warmth on my skin that really lifts my spirits, the sense that winter has passed and that life is returning. These first few days of spring, though changeable, mean more to me than the warmer, predictable, days of summer and I suspect that it is the sense of renewal that makes this season so special.

The dawn air rings with the calls of rooks. Settled at their rookery, there is much society to be had as pairs reinforce bonds or bicker with their neighbours over the ownership of sticks destined for the nest. The clear skies and lack of foliage show the rookeries off at their best, the birds striking in their black feathering and bone white faces. While other birds are singing to attract a mate or are still on their way back from African wintering grounds, the Rook breeding season is well advanced. Most Rooks will be incubating a clutch of four or five eggs by now and it will not be long before there are hungry young in the nest. The blue-green eggs, with their pattern of speckles and blotches, were once the unfortunate targets of egg-collecting children and it would have been a fearless youngster who sought out these nests, perched precariously within the fine outermost branches.

In addition to the avian activity, the first of the season’s insects are on the wing. Most obvious of these are the butterflies and queen bumblebees, newly emerged from their winter slumberings and in need of nectar to replenish resources metabolised during the dark days of winter. The queen bumblebees seek suitable nesting chambers in which to initiate a colony that will grow in size through into autumn and the next major change in the seasons. I love watching these bees as they buzz about noisily, peering into each potential nest site before lumbering on somewhere else until the perfect site is found.

This spring seems to have started with good numbers of hoverflies foraging at early season nectar and there have even been reports of Hummingbird Hawk-moths active within the county. These are either recent emigrants or, more likely, individuals that arrived late last autumn and which have, somehow, managed to survive the winter.

With the leaves yet to form on the trees, there is a flush of green across the woodland floor. These are plants that manage to take advantage of the short gap between the end of winter and the restoration of a new summer canopy, after which the woodland floor will be plunged back into shade. Visit an old woodland, like Bradfield Woods (just over the border in Suffolk) and you will be treated to a fine display.

Fenland rooks greet a rosy dawn

There is no denying that the fenland landscape can be bleak, dominated as it is by vast skies and little else to break the spirit-level flat horizon. Dull winter days bring brooding skies, the colour leaching from the land and only the deep peaty darkness of the rich black soils remains. The wildlife often seems pushed to the margins and the intrusive sounds of farm machinery and overhead aircraft remind you that this is a landscape in servitude to our needs.

At the same time, there are moments when the Fens can deliver great beauty and, sometimes, a sense of remoteness and closeness to nature. The other morning, for instance, I found myself at Ely station, waiting for a connection into Cambridge. It was still early and a broad sweep of horizon was blushed with soft purples and reds, a legacy of the changing weather and a weak winter sunrise. The sky, deeply patterned, was stunningly beautiful, with a real sense of depth. The feeling of great distance, a sense often felt in these flat lands, was further deepened by the stark silhouettes of distant poplars, two fields away. Few of my fellow passengers seemed to notice the breaking dawn, suffuse with colour. Perhaps they were too engrossed in their phones, papers or morning coffee to notice the spectacle of this particular fenland morning.

Above the murmurings of chattering people could be heard the more strident calls of Rooks, a steady but loose stream of birds crossing the sky and most likely freshly emerged from a communal overnight roost. The calls of these birds, less harsh in tone than those of the equally familiar Carrion Crow, are one of my most favourite farmland sounds. To me, these early nesters herald the approaching spring and it is a delight to see them present in such good numbers. They hint at the first stirrings of spring, of what is to come with the passing of a few more weeks and with the strengthening sun.

The colour of the sky soon changes and the beauty slips away as the colour slides from purple into grey. Then the moment is gone. My train arrives and I manage to grab a window seat to watch the landscape roll past me: dark soils, narrow ditches and fields that appear as vast lakes, so well are they covered in warming polythene. A small group of Whooper Swans loafing in a field, a flight of wild duck and a thick-coated Roe buck, all slip by. There are days when I love the Fens and others when I struggle to find any attachment, so bleak do they seem. There is, however, always some emotional response to this great landscape.

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.

Rookeries buzz with activity

I have noticed a great deal of activity in the local rookeries over recent days, as pairs add sticks to their nests and indulge in a spot of petty theft from those left unattended. There is a real sense of excitement, with the first eggs likely to be laid within the next two weeks. Since Norfolk is a county dominated by agriculture it should come as no surprise that we have such a large population of breeding rooks. The most recent survey, carried out by the British Trust for Ornithology in the mid-1990s, estimated that there were 17,600 nests located in 340 rookeries spread across the county. This represents an increase on previous figures, perhaps a reflection of a run of mild winters, coupled with the ban on stubble burning and the increasing number of outdoor piggeries. These last two changes will have increased the amount of food available to these farmland specialists. My own impression is that they have continued to increase and that there are now many more rookeries to be found within the county. Some of these are small, numbering a few pairs, such as the one alongside the B1108 just outside Watton or that close to the heart of Wymondham. Most rookeries sit high in tall deciduous trees and at this time of the year, before bud-burst, the large nests are obvious. Others are in conifers and I recall one in hawthorn scrub at Bunwell. I have also heard of a few rooks nesting on the pylons that run alongside the Norwich southern bypass at Keswick.

Although rookeries may seem noisy, disorganised affairs, there is a structure and hierarchy to them. Dominant birds, typically well-established pairs that have bred together over several seasons, will occupy nests at the centre of the rookery. Presumably this gives them the greatest protection from predators and the elements. Less-experienced pairs, usually young birds, are forced to nest on the periphery of the colony and these are more likely to fail through a combination of position and lack of experience on the part of the birds themselves. Although both members of the pair construct and defend the nest, it is the female who incubates the eggs and broods the chicks. During this period, as Gilbert White noted in his journal of 1775, the male provides the female with food. Although the breeding season diet is dominated by invertebrates, the rook is omnivorous and has developed a reputation for taking grain. Despite this, rooks are tolerated across much of the county, though some are still shot each year and the loud thump of a gas gun remains commonplace. Not that such measures seem to have halted the increase of this wonderful bird.