Changing waterfowl require greater understanding

The latest review of waterbird populations in the UK makes interesting reading. At first glance it suggests contrasting fortunes for many of the species with which we share these islands. The review, jointly published by the BTO, RSPB and JNCC, stems from the efforts of some 3,000 volunteer counters. These volunteers participate in the synchronised monthly counts that take place across our many inland and coastal waterbodies.

While some species reached new ‘highs’ in terms of their population levels, others reached all-time lows. An examination of the ‘winners’ and ‘losers’ reveals that many of the ‘winners’ are introduced species whose naturalised populations continue to expand. These include Egyptian Goose, Mandarin Duck and Barnacle Goose. However, in with these are genuine colonists like Little Egret, a species expanding north on the back of global climate change.

The numbers of some species reflect breeding conditions elsewhere, the UK being a wintering ground with little or no breeding population of its own. A poor breeding season elsewhere may see fewer birds available to make the journey to our shores. The recent downtown in wintering numbers of Bewick’s Swans was once thought to be linked to a contraction eastwards in the wider European wintering range. However, recent research has revealed a decline in the overall population rather than just a shift in distribution. In contrast, our population of wintering Whooper Swans has continued to increase, with most of our visiting Whoopers arriving from Icelandic breeding grounds. The nature of the survey also enables the volunteer counters to gather information on breeding success for some species. In the case of the Whooper Swan, cygnets accounted for 16.8% of the birds present, slightly up on the previous winter.

The estuaries around Britain & Ireland are important wintering sites for many wading birds and these are also surveyed by the volunteers. Again fortunes appear mixed, with some notable increases seen in Avocet (a real conservation success story), Grey Plover and Sanderling. Balanced against this is the apparent news that Ringed Plover and Dunlin have both hit all time lows. Britain has eight sites of international importance for Ringed Plover but, while the decline might seem worrying, news of increasing numbers at sites elsewhere in Europe (notably The Netherlands) suggests that what we are actually seeing is an eastward shift in the core wintering range, perhaps linked to a run of mild winters.

Taken as a whole, this report highlights the need to monitor the changing fortunes of these birds at a much wider spatial scale, since a decline here may not mean that the population is falling, merely that it is now wintering elsewhere. Fortunately, our knowledge of waterbirds is increasing, placing our understanding into a wider context.

All in the eye

I have been reading Carry Ackroyd’s book about the Fens and the influence it has on her work as a printmaker. The subtitle of the book ‘Landscape Change John Clare and Me’ bears testament to the hold that this unique landscape has had on artists and writers down through the years. John Clare, often referred to as the peasant poet, documented the loss of ancient countryside to the changes he saw in farming practices. Working as a farm labourer, he was connected with the land in a way that other poets writing on natural history could never be; this shows through in his detailed observations and closeness to the subjects of his lines.

A key element of Carry’s work is the natural history that sits within her fenland landscapes. She is not just documenting the land but also the creatures that are an integral part of it. In this way, her work is refreshingly different from a traditional view of ‘wildlife art’, with its simple presentation of animals and birds divorced from their surroundings. In fact, Carry is part of a wider movement away from the tired images of lions, elephants and eagles that were once the mainstay of wildlife art. For me, art should stimulate an emotional response from the viewer and wildlife art should be no different. Whether it is the sense of space that comes from Carry’s fenland views or the tension of Andrew Haslen’s Brown Hares, crouched low within their Norfolk forms, good wildlife art connects you with the landscape or creature that you are viewing.

I have always been influenced by the tones of nature, be they the purples of the autumn heathland where I grew up or the olive-green of hares within a winter field. It is these qualities that reach out to me from prints and paintings, along with subtle shapes that bring life to birds or animals captured in two or three dimensions, shapes that echo my own recollections of seeing these creatures in the field.

Art is very much about personal taste; being able to view a group show in a gallery provides the opportunity to discover what it is that you most connect with. As well as the grand opportunities provided by the art marquee at the BirdFair in August or the SWLA show in London in September, there are local galleries – notably at Cley, Glandford and Lavenham – where you can see a wide range of art by wildlife artists.

The Natural Eye, the 47^th exhibition of the Society of Wildlife Artists, is being held at the Mall Galleries, London from Wednesday 22^nd September until Saturday 2^nd October. For more information, visit www.swla.co.uk

A subterranean way of life

Rake through a piece of woodland leaf litter with your hand and you may well come across a cobweb-like mat of fine white threads. These are fungal hyphae; they are building blocks of filamentous fungi, thin cylinders that contain cell nuclei, mitochondria and other life-defining organelles. The fungal fruiting bodies familiar to us as mushrooms and toadstools are formed from hyphae and great empires of these threads carpet the soil and shroud the rootlets of trees and shrubs.

Fungal hyphae show certain similarities to the roots of plants, not least in that they absorb nutrients from their surroundings, acquiring resources to support growth and, ultimately, the production of the fruiting bodies that will disperse their spores. The hyphae also produce digestive enzymes, which digest the material in which the hyphae are growing. Most typically these enzymes digest cellulose – think of all the fungi you have seen growing on dead wood, but others digest keratin (hair and fur) or chitin (the material that forms the exoskeletons of insects). There are even fungi (in the broadest sense) that produce enzymes which can digest kerosene!

Many of our familiar fungi are associated with trees; rather than occurring loosely in the soil, their hyphal networks accumulate around the rootlets of certain trees and larger shrubs. Some of the hyphae grow into the rootlet, forcing their way between the tree’s cells. This association is not as one-sided as you might imagine, since it is not simply a case of the fungus attacking and feeding on the tree’s tissue. While the fungus receives moisture and nutrients from the tree (the latter most likely as by-products) the tree receives access to the soil nutrients being harvested by the fungus. The structure of this close association, the rootlet and the hyphae, is known as a mycorrhiza or ‘fungus-root’.

Knowledge of fungus-tree associations can be particularly useful when seeking to find or identify certain fungi. There are, of course, a number of species that are generalist in their habits, and which are associated with a number of different tree species, but others are rather choosy. Fly Agaric, for instance, seems to favour mature birch trees (invariably those of 15 years age or older) or, to a lesser extent, pines. However, other features probably also have a roll to play, notably soil pH, soil condition and how wet the soil is. The sight of fruiting bodies at this time of the year reveals the presence of fungi that exist beyond our gaze for the rest of the year. The weather seems to have been favourable this year and there is a rich crop of fungi to be found across the woods, heaths and grasslands of Norfolk.

The last orchid of summer

Gather a group of naturalists together and the chances are that they will find something interesting to look at and to talk about. Last weekend, a friend’s wedding in Holt brought together a number of naturalists and, in the interval following the meal and speeches, we were able to pop outside and see a colony of Autumn Lady’s-tresses. This delicate little plant, the last of the orchids to flower each year, is a rare species in Norfolk and the opportunity to view it was not one to be missed.

Each plant is small (just 15 cm or so in height) and fragile in appearance. Approaching the lawn, I became aware of a smudge of white sitting just above the green of the lawn itself and creating the illusion of a thin low mist. This effect was caused by the white flowering spikes of Autumn Lady’s-tresses, a vertical spiral of crisp mint-white tubular flowers. To appreciate the flowering spikes fully, you had to get down on your hands and knees – no doubt a comical site to anyone watching us in our wedding finery. These orchids were very much my kind of plant; not garishly bright and shouty but soft and understated. Most had a dozen or so white flowers spiralling up the stem, some spiralled clockwise and others anti-clockwise. There were even a few plants which showed hardly any spiral at all.

Since the flowers open in succession, from the base of the stem upwards, there were some that had finished flowering but with others yet to open. This strategy helps to prevent self-pollination, the plants attracting bumblebees to carry pollen from one plant to another. This approach works well and cross-pollination is pretty much guaranteed. Even so, these orchids can reproduce vegetatively if necessary. Autumn Lady’s-tresses is a plant of southern Britain and is most commonly encountered south-west of a line running from Monmouth to Hastings but there are scattered colonies as far north as Cumbria. Many of the sites on which this orchid once occurred in East Anglia have been lost, invariably areas of damp grassland now drained. Autumn Lady’s-tresses is associated with short nutrient-poor grassland, where it is released from competition from larger and more dominant plants. This old lawn in Holt makes an ideal site, with careful mowing and control over the addition of nutrients keeping potential competitors in check. Proof of the success of the management approach can also be seen in the large number of grassland fungi recorded from the site. Since this species has been lost from more than half of its former range in Britain, it is reassuring to know that this particular site is likely to be secure for many years to come.

Wryneck

In yesterday’s column I touched on the arrival of east coast vagrants, birds that had been drifted to our shores while on their autumn migration south. One of these, the Wryneck, deserves a more detailed piece, not least because of its rather unusual character.

The first thing that strikes you about the Wryneck is its size. As a member of the woodpecker family I’d always expected my first Wryneck to be a substantial creature, similar in size to a Great Spotted Woodpecker. Instead, the small and slender bird that greeted me prompted the involuntary comment ‘it’s tiny!’ In terms of body length the Wryneck is only a little smaller than a Starling but it is of slighter build, a characteristic further emphasised by some of the postures that it adopts. As a child I had a similar response to my first Mole (found dead by the side of the road) and Kingfisher (glimpsed on a local stream); both were significantly smaller than I’d imagined.

With its brown, grey and black vermiculated plumage and its short but pointed bill, the Wryneck doesn’t look like your typical woodpecker either. Unlike other woodpeckers it does not use its tail for support when climbing, nor does it hammer with its bill, preferring instead to chisel away. It can sometimes be seen perching crossways on a branch (again rather unwoodpecker-like) and even its flight bears little resemblance to that of its relatives. Most of the Wrynecks I have seen have been on the ground, either on coastal dunes or the lawns of suburban gardens. In both of these localities the birds will have been foraging, searching the ground for ants.

For me, part of the attraction of the Wryneck is the folklore with which it is associated, even though most of this lore remains firmly rooted elsewhere in Europe. Of particular interest is the name ‘snakebird’, which was used widely across southern England when the bird once bred here in good numbers. This association comes from the defensive display, in which the bird writhes its head around in a strongly reptilian fashion. I have been told that this behaviour is all the more striking when seen at the nest hole, since here the chicks also indulge in the writhing display, occasionally darting out their tongues and all the while uttering a most snake-like hiss. This behaviour, and its effect on nest-robbing children, is wonderfully described in John Clare’s poem ‘The Wryneck’s Nest’.

In the ancient world the Wryneck was ascribed magical powers and associated with various fertility rites. It may have been the bird’s snake-like behaviour that first suggested magical properties, since snakes were strongly associated with fertility. Even now, there is something magical about the Wryneck.

On the move

Early autumn fogs hold the prospect of vagrants from the east. Small migrant birds, setting off from Scandinavia under clear skies, may find themselves drifted west across the North Sea. Here they may encounter a bank of fog or rain, which forces them down on to the East Anglia coast. If the combination and timing of these meteorological conditions happens in a certain way then many hundreds or even thousands of birds may seek the relative security of England’s east coast. This is a truly exciting event for the birdwatcher and an early morning walk among the dunes at Winterton or along the long shingle ridge towards Blakeney Point may yield some stunning birds. The sight of hundreds of Robins or Pied Flycatchers is one not readily forgotten. In with these more familiar migrants may be less commonly encountered species, including various warblers, thrushes and other delights.

Frustration comes when the forecast shows real promise and you have a full day of work ahead, with no prospect of an early morning dash to the coast. The walk out to Blakeney, which is to be recommended, is at least a half-day affair and not something you can squeeze in before work. It is a strange place, an exposed and empty landscape, touched by the hand of past human activities to leave a desolate air. In the clearing mists of early morning, ridges of shingle take on weird shapes and the landscape appears all the more alien. I sometimes feel as if everything else has gone, that human society has disappeared and all that is left are vague echoes of our presence in the form of discards from passing ships and former inhabitants of the point.

The Point at Blakeney has held some nice birds over the last two weeks, with one of my favourites – the Wryneck – reported by visiting birdwatchers. There are some birds that seem ideally suited to a particular place or landscape and the Point is the place that I most strongly associate with the Wryneck. This diminutive member of the woodpecker family was once a regular breeder across much of England but now it is effectively extinct as a breeding species – a real loss.

The arrival of these autumn migrants feels somewhat early this year, no doubt a reflection of the cold autumnal spell felt in the last two weeks of August. I usually associate late September and early October with visits to the coast to watch visible migration in action (the sight of pipits and thrushes passing south at dawn) or to seek out some of our rarer visitors. Even now, the long walk on shingle might be hard work but the rewards are likely to be worth it.