Basin Notes - January 2006

Successful migrant flexible in its feeding

The advantage of a small brain may not be immediately obvious; the bird brain copes with the navigation problem of long flights from the wintry north to southern sub-Saharan climes, in due course returning to the Northern Hemisphere.

The successful migrant is flexible in its feeding habits. Partial migrants - birds such as oystercatcher, curlew and lapwing, as well as resident flocks such as redshank - will have their food source sussed to carry them through the harsh periods of wintry weather.

Our pink foot geese, which return to Iceland and Greenland, have to adapt to what is available. This year there is an abundance of carrots in the fields. The carrot harvester tops and tails, the nugget goes off to the supermarket and leaves residual feed in the drills. Thrushes arrive from Scandinavia when snow and frost have clamped down on their feeding, so large flocks of redwing, fieldfare and wax-wing arrive on our shores - heading as likely as not into Glen Esk, where berries are still plentiful.

At Mavisbank near Farnell, Scotia seed merchant Gilles Laverack is growing Scottish native wildflowers and grasses, etc. The fields of hay and wildflowers are really lovely and attractive to larks whose tremendous lark song fills the air with joyful noise. Native wildflowers are increasingly marginalised with toeholds on roadside verges, clifftops and ditches and hedgerows. Some measures are being taken to correct this state of affairs.

Conservation really is very dependent on our farmers. Even high moorland plants, which have to tough it out through the winter, adapting to grow in cushions, also have to survive the severe damage caused by grazing animals. Very special care and monitoring of these unique areas at the head of our glens is essential to conserve what we have. Young trees are equally vulnerable to the red deer and those trees which give animals, birds and insects shelter such as the Scots Pine need the help of conservation-ists to keep their populations from dying out in the glens.

One tree which established itself in Scotland after the last Ice Age and even before the Scots Pine is the Aspen It is an indicator of ancient woodland. However, forestation has separated the colonies of Aspen and even ancient oak woods seldom have many Aspen left.

The oak woods were utilised for, among other things, iron smelting - although the Aspen was perhaps less valued by the foresters then. Some isolated specimens of Aspen have spread but this is a clone colony - all male or all female - having little possibility of pollen transfer from other Aspen.

Several specialised lichen are found on the Aspen. Likewise a moth, the Dark Bordered Beauty, has an affinity for the newly emerging bronze coloured leaves which are its preferred food Aspen hover fly is also uniquely adapted to breed on the dead wood of this tree. There are several small colonies of Aspen in the eastern Cairngorms.

As days lengthen and spring flowers start to emerge, we can look forward to the lovely show - snowdrops, primroses, lesser celandine and aconites followed by bluebells carpeting the woodland floor Ladies' tresses, bedstraw and wood anemone will quickly get going before the coarser grasses take over These all encourage a walk or cycle run in the countryside to enjoy the splendid show.