Monday, 11 October 2010

Signs of the times: Summer #20

More comparisons between the British countryside of today and that from 1959-1961 in the paintings of Charles Tunnicliffe in the Ladybird "What to look for..." series of books.

Relatives are the worst friends, said the fox as the dogs took off after it.”

Anonymous Danish proverb

(Copyright: Ladybird Books)

Summer Picture 20
A moorland scene that could be from Scotland, Yorkshire or, at the time the book was published, Cumberland. Let us, from my Scottish bias, assume it is a Scottish moorland. A small flock of red grouse look on as a red fox, a potential predator, is running off to the right of the picture. A dipper sits on a rock in the stream, above some small brown trout sitting in the current. Both the bell heather and the ling heather are in flower, with small dark blue fruit growing on the bilberry plants in the bottom right. A high-brown fritillary butterfly flutters nearby, while an emperor moth caterpillar is feeding on the ling heather. We’ve looked at the brown trout in an earlier post, here, so I won’t discuss it again now.

The red grouse (Latin name: Lagopus lagopus) is a native game bird, the distinctive dark-winged scotica race being endemic to Britain and Ireland and with the great majority of its population within the UK. Those unfamiliar with it may well recognize it as the cartoon caricature bird that stars in the amusing adverts for “The Famous Grouse” blended Scottish whisky. The British Trust for Ornithology describes how the red grouse is economically very important to some rural communities as a game bird and has benefited from intensive management of many moorlands, designed specifically to increase the numbers of grouse available to be shot. There are no accurate survey figures for red grouse populations going back to 1960, but BTO shows that there have been fluctuations in red grouse populations, but no overall trend, since 1994:

Shooting bags, from figures collated by the Game and Wildlife Conservation Trust,  (i.e. the number reported as having been shot) have revealed long-term declines, apparently driven by the loss of heather moorland, increased predation from corvids (crows and ravens) and foxes, and an increasing incidence of viral disease. In conservation terms, this decline resulted in the moving of this species from the “green” (safe) list to the “amber” list. The BTO’s account does an excellent job of summarizing the complex and complicated interaction of natural processes and human interference affecting grouse:  “Longer-term trends in Red Grouse abundance are overlain by cycles, with periods that vary regionally, linked to the dynamics of infection by a nematode parasite ... Raptor predation is believed not to affect breeding populations significantly, although it can reduce numbers in the post-breeding period ... Hen Harriers in particular can reduce grouse shooting bags, limit grouse populations and cause economic losses to moor owners, and have been subject to much illegal persecution ... Finding a solution to the harrier–grouse conflict would bring considerable benefits to the management of the UK's heather moorlands and have broad implications for the conservation of predators.”

And on the subject of predators of red grouse… Most people probably don’t think about it in these terms, but the red fox (Vulpes vulpes) is Britain’s only surviving native wild dog species, following the elimination of the last wolf in the 18th Century and, possibly, the prehistoric retreat northwards of arctic foxes with the retreat of the ice fields of the last Ice Age. The Joint Nature Conservation Committee’s review of British mammals provides an estimate of the fox population of Britain as around 240,000, of which Scotland has around 23,000. The JNCC reports that the fox population of Britain is probably still growing, including the phenomenon of urban foxes. As you’ll know if you watch the BBC Springwatch programmes which always seem to feature films of them, foxes are increasingly found in urban habitats, with around 3000 urban foxes estimated in Scotland.

A few winters ago, we had a resident fox living in or around our garden, much to the frustration and occasional excitement of Ella the Wonder Dog. It made its way around the area on the top of the six foot high walls between the gardens and, where we had a large growth of ivy growing over the top of the wall, it used to sleep there, under the ivy cover, curled up with its large tail (or brush) wrapped around it. Occasionally we would see, reflected in our torch light, a single shining eye open up to check that we weren’t approaching too closely, but otherwise it ignored us completely... whereas every time the fox was “staying”, Ella ran back and forward in a frustrated growling frenzy, at the bottom of the wall!

No doubt there is still active game-keepering activity on the grouse moors of Britain, perhaps accounting for the nervous disposition of the fox in this picture! There’s lots more to say about the fox’s place in British ecology and culture, but the fox, and fox-hunting feature in the Autumn book, we’ll revisit this later in the year (but not too much later).

The dipper (Cinclus cinclus) is the little dark brown, chestnut brown and white bird standing on the rock in the stream. It is unique among the passerine (or perching) birds of Britain as the only one that feeds from the bottom of streams and rivers, plunging in, walking upstream into the current and feeding on riverine insect larvae and other stream invertebrates ( it isn’t the ONLY species that dives into freshwaters to feed though – consider the kingfisher!). The BTO provides a picture of the long-term fate of Britain’s dipper population. Dipper populations have fluctuated over the last thirty years, but with an overall downward trend:

Dippers are very sensitive to the acidification of rivers (from acid rain), which leads to the loss of their invertebrate prey. Not surprisingly, the acid rain problems of the 1970’s badly affected dippers in the uplands where acidification was worst. Since 1975, there has been a 30% decline in the dipper population, although there is probably now an ongoing recovery from acid rain problems in many of Britain’s worst affected freshwaters in recent years (I can find you evidence if you need it!). I speculated previously here on the possible recovery of dippers. In our recent Corsican adventure, we were surprised (presumably unreasonably so) and delighted (not unreasonably) to see dippers regularly in the rocky river running through the mountain city of Corte.

The overwhelmingly dominant plant in this picture is heather. The painting purports to show two species, bell heather (Erica cinerea) and ling heather (Calluna vulgaris). Erica cinerea, named bell heather on account of its small purple bell-like flowers has ,according to the New Atlas of the British and Irish Flora, declined in southern England from loss of heathland habitat, and has disappeared from many former 'chalk heath' sites through encroachment of rank grass and scrub following reduction in sheep and rabbit grazing. The ling heather (Calluna vulgaris) is also reported in the New Atlas to have declined as suitable habitat has declined greatly, particularly in much of England, “since 1950 through loss of heathland to forestry, agriculture, mineral workings and scrub. It cannot tolerate continued heavy grazing, and has declined in some upland areas for this reason.”

According to Tess Darwin, in “The Scots Herbal”: “Of all Scottish wild plants, the prize usefulness must surely go to heather. In a typical dwelling in many parts of Scotland until this century, heather might have been found in the walls, thatch, beds, fire, floor mats, ale, tea, baskets, medicine chest and dye pot, being used to sweep the house and chimney, to feed and bed down sheep and cattle and to weave into fences around the farm”. Phew! Also, very sagely, she points out that, while many people consider heather to be just as much of an emblem of Scotland as the thistle, although heather moorland is “an artificial and degraded landscape created by deforestation and maintained by over-grazing of sheep and deer and burning for grouse management.” Phew!

The bilberry (Vaccinium myrtillus) in the extreme bottom right of the picture, known in Scotland as the blaeberry and in Shropshire and the Welsh Marches as the wimberry, is also a member of the Heather family. Blaeberries are an important wild food resource, the collection of which in Britain took a bit of a dent following the contamination of many British upland areas by the Chernobyl explosion’s fallout. Tess Darwin points out that, as well as a food source, in Scotland, they have also been used as a treatment for kidney stones and as a dark purple blue dye for cloth. The New Atlas reports declines in the blueberry from the edge of its range: “in England since 1950, reflecting the loss of lowland heathland. It has also declined in C[entral] Ireland, probably for the same reasons. Elsewhere it remains common in suitable habitats.” My wife is obsessed with harvesting blaeberries when we find ourselves among fruiting bushes when out hill-walking. In such circumstances, there is little point in me expecting to go any further for some considerable time.

Just to finish off this rather long post, there are two insects featured, the high brown fritillary butterfly and the caterpillar of the emperor moth. The high brown fritillary (Argynnis adippe) has, since the 1970’s, suffered the greatest distribution decrease of any surviving butterfly species in Britain and is now one of our most threatened species. The NGO for butterflies, Butterfly Conservation reports a 79% decline in distribution, and a decline of 85% in monitored populations between 1995 and 2004. This may all be down to changes in the way that moorland and upland forest edge habitats have been managed, as positive habitat management in England has brought about local increases in populations. The emperor moth (Saturnia pavonia) is common across Europe and its caterpillar feeds on bramble, heather and other shrubs. I couldn’t find any detail about how it is doing in Britain, although I did read that emperor moth males can detect the pheromones of the females up to five miles away.

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