Conservation and Natural History in the Rannoch area

Rannoch Net

 

Scottish Mink Initiative

Rannoch is an area of great scenic beauty and one which has been a Mecca for biologists and conservationists since last century. Ten thousand years ago the ice, which covered Scotland retreated and the land became clothed in a spacious pine forest from coast to coast. Scots pine was the dominant tree, supported by rowan, birch, oak and juniper. Man burned or cut most of this forest to flush out bandits and exterminate the wolf, however a few important patches of the original forest remain. These include the Rothiemurchus and Abernethy forests and the Black Wood of Rannoch.

The Black Wood is owned by the Forestry Commission and jointly managed by the Commission and Scottish Natural Natural Heritage. The northern part is a minimum disturbance area which is not touched at all. There is some active management in the outer regions. Scottish Natural Heritage is trying to extend the wood by removing exotic species to allow the native species to propagate.

The Black Wood lies immediately to the west of Rannoch School (Dall) and features splendid pines, some hundreds of years old. Rannoch School assisted in a number of biological investigations. Aberdeen University came to the school to study Capercaillie. From time to time birds became very tame in the spring and they wandered about the school taking little notice of people. There is a photograph in an old school magazine of a female capercaillie sitting on the (stationary) rotor blade of a helicopter which came to the school.
The Institute of Terrestrial Ecology has fenced off a number of areas of the Black Wood to study the effect of deer grazing on the regeneration of pine, rowan, and birch. It is clear that regeneration is much more obvious in the fenced areas. The school was enlisted in the institute's survey of red deer. This involved half the school forming a human wall to drive the deer through the trees towards the counters. Pupils also benefited from tuition on the information provided by deer droppings. Droppings featured large in a survey of otter and mink along the Dall burn. Otter spraints (droppings) were found at a number of places along the burn. Mink are relatively common in the area, numbers having escaped from fur farms near Pitlochry a long time ago. Another prominent member of the Mustellidae is the pine marten, which has spread into the area during the last 14 years. Pine martens appeared at one member of staff's house as a welcome visitor. Stoats and weasels are fairly common mustellids but the badger is relatively rare.(Mammals)

Rannoch school assisted the Nature Conservancy (now SNH) in surveys of insects, plants and fungi in the Black Wood (Peter Orton, a former member of staff of Rannoch School was a world expert on one particular genus of fungus found in the Black Wood, called Cortinarius). He was also a very good entomologist and discovered many insects new to the list for the Black Wood. There are two moths that have been named after the area, the Rannoch Looper and the Rannoch Sprawler. Butterflies are not terribly common but Painted Ladies, Scotch Argus, Green-veined White and Northern Brown Argus are to be found. There are also two species of dragonfly which are almost peculiar to the Rannoch area. An interesting feature of the Black Wood is the Scottish Wood Ant (Formica aquilonia) which is very similar to the English Wood Ant but which is hairier. It makes large conical nests from pine needles and twigs. The presence of these nests is a good sign of the ecological health of the Wood. The nests are designed to warm up in the sun so that the ants, which are cold-blooded can become active as soon as possible. The ants are largely camivorous and will overpower other insects using their jaws and squirting jets of formic acid. They are well known for tending the aphids (greenfly) which are found on all sorts of vegetation but especially the Scots pine. The aphids are protected from predators and parasites by the ants and in return they provide honeydew which is a sweet substance rich in carbohydrate. The honeydew is the aphids excretory product and is held on a ring of hairs around the anus of the aphid before being ingested by the ants. The ants themselves fall prey to predators and parasites that live in their nests. Some of these produce sweet substances to fool the ants into not attacking them. A larger predator is the Green Wood Pecker which digs into the nest with its beak, making a conical hole from which it gathers ants using its long sticky tongue. Its tongue is so long that it has to be wrapped in a special track around the back of the skull. It is thought that regeneration of the native Caledonian pine in the Black Wood is hindered by browsing deer (both red and roe) and these animals are culled by the forest rangers. Regeneration seems quite strong along tracks where there is light and where the ground is disturbed. tracks are also good for the discovery of cones eaten by either red squirrels or cross bills, each leaves distinctive signs. There are adders to be found but no grass snakes, perhaps because adders are oviviviparous (which means that the eggs hatch inside the female and then it gives birth to live young) while the grass snake is oviparous and has to find somewhere for its eggs to be incubated. Common lizards abound in the hot summer and the slow worm is common. The latter is often mistaken for a snake but it is, of course, a legless lizard and is able to shed its tail if attacked, as is typical of lizards. The idea here, is that the predator will delay, eating the tail while the lizard escapes and grows another tail.

Loch Rannoch (a ribbon lake) is eleven miles long and 1.5 miles wide at its widest point. It is sufficiently large to sport large breaking waves in windy weather when it can look quite like the sea. It has an interesting population of Charr (Salvelinus alpinus) which was the subject of a taxonomic study at Rannoch School. This was funded by the Royal Society under the 'research in schools scheme'. Charr populations seem to have been isolated from each other in deep lakes, since the end of the last ice age and races or subspecies have evolved. It was thought that the Loch Rannoch Charr might belong to two separate populations, one deep water and the other shallow water.


Other fish that occur in the loch are pike (which are netted by the Loch Rannoch Conservation Association to reduce there predation on trout), brown trout, salmon, perch and some rainbow trout. The rainbow trout were introduced and may be disappearing as they do not breed. It is now policy not to introduce any but native, locally bred fish when stocking the loch to avoid genetic pollution.
The fish research laboratories at Faskally have a long running project to 'seed' burns around Loch Rannoch with salmon parr to encourage a larger returning population. The original population having suffered from the difficulty of returning past the hydroelectric darns in the Tummel system. The dams have fish ladders but these apparently still represent a formidable barrier. Assessment of the population is done by stunning fish in the burns with electric probes. The fish are unharmed and can be returned to the water.


The Royal Society for the protection of birds keeps a weather eye on the birds of prey in the area and was grateful for the assistance from members of staff of the school who discovered a photographer in a local eagle eyrie, making the eaglet flap its wings so that he could get a better photograph. we were able to take his car registration which was traced to an address in Lancashire.
Other birds of prey of note in the area, include hen harriers, short eared owls, merlins, peregrine falcons and ospreys. The latter seem to be getting quite common;

In autumn the loch and local reservoirs play host to numerous ducks (mallard, teal, wigeon, pochard, tufted, goldeneye, red-breasted merganser, goosander) and geese (greylag, pink foot). Hundreds of greylags spend the winter but are not always popular with the farmers. The geese are accompanied by whooper swans and one pair of these stayed to breed, an unusual event. Unfortunately the pair had their eggs stolen and failed to breed although they had had four cygnets the previous year. Black throated divers breed on the larger lochs and red throated divers breed on smaller bodies of water. One small loch has been the breeding site of the rare Slavonian grebe.(Birds)
Rannoch School Conservation Service has worked with the Countryside Commission to set up an information board and parking area at a local disused lime kiln. The kiln was repointed and made safe, trees were planted and the board describes its history and technical details of the function and functioning of the kiln.
The service also helped restore stone dykes at Kinloch Rannoch. We hope to help Bristol University with its survey of British hare populations. We have both brown hares and the mountain or blue hare.

The encouragement of native species and their reintroduction has been a long term policy but is perhaps gaining pace. The capercaillie was reintroduced from Scandinavia after going extinct in Scotland. The red kite has been reintroduced to Scotland after having gone extinct in Britain except for the Tregaron bog area of mid Wales. The Caimgorms are quite famous for their reindeer which were brought from Sweden. The white-tailed sea eagle is now reasonably common on the cliffs of islands such as Rhum, again after reintroduction from Scandinavia. At one time it nested on Rannoch Moor and was, in fact, more common than the golden eagle but proved less adaptable. In Roman times these eagles fed on bodies after battles. It is interesting to note that a brief newspaper article claimed that brown bears had been released in the area of Amulree. This is presumably not the case and would not really be a feasible proposition because of the potential conflict with human activities. As yet I have heard of no plans for reintroducing the wolf or lynx but perhaps Rhum would be a suitable site.
Rannoch Moor is a site of international importance, since it is a national nature reserve and here the Rannoch rush which is peculiar to the area is to be found. It is perhaps fortunate that a road has never been built across the moor or it would have changed the character of the area. There is nevertheless a railway, the West Highland Line. In places the line is built on brushwood which cunningly prevents it from sinking into the bog.


The Rannoch area is blessed with an unusual limestone called the Dalradian limestone which is 600 million years old. The lime which it provides to the soil has an influence on the vegetation and is favourable for certain plants such as the Northern Felwort, Astragalus, thyme, bottle sedge, rock rose, wild strawberry and globe flower to name but a few. The limestone pavement on the Schiehallion road is one of the best in Scotland and all the more mteresting because it is in Dalradian limestone. The grykes (furrows) in it protect the original woodland plants from grazing and contain, Dog's Mercury, Herb Bennet, Ivy, Wood Sorrel and Wood Anemone.
Further to the east an on going conservation issue resides in the barytes deposit at Farrogon Hill. Barytes is a mineral (barytes is a mineral (barium sulphate) which is used as a drilling mud in the oil wells of the North Sea. The MI mineral company now exploits the resource with consequent very heavy lorries crossing Wade's bridge in Aberfeldy and disturbance of the hillside with heavy vehicles. The mining has brought to light a rare mineral called celsian which is a barium feldspar and which has caused some of the site to be declared an SSSI. The barytes deposit continues further east to Cluny Moor where the deposit is even purer and will be of use for medical purposes. (it is used for barium meals and enemas since it is opaque to X-rays). Whether or not to exploit the Cluny Moor barytes is the subject of a public enquiry.(Geology)

The John Muir Trust is a conservation body which is devoted to preserving the wild areas of Britain.

Natural History

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