Basin Notes - January 2003

Some like it wet!

What dreary wet weather we've been having recently. "Nice weather for ducks" I hear you say, but do ducks really like this weather?

The answer is probably "yes", otherwise they would not be here. The great mobility that flight affords bird species means that they can move quite rapidly away from danger. So a fox, a fast moving car, or bad weather are all avoidable if you are a bird.

So Montrose Basin (and any other wintering site) must have a lot of things going for it if the 8,500 ducks that are floating around on the water at the moment are happy to stay. In addition, there are close to 6,000 wading birds here as well.

For a lot of the waders, the current temperature is much higher than it is at their breeding grounds, which are at high altitude or high latitude (within the Arctic Circle). They deliberately come to Scotland because of it's relatively mild conditions in winter.

Even so, they cannot afford to waste energy, and can be seen in large numbers at high tide packed together on roosts like Rossie Spit. Staying together reduces the cooling affect of the wind as the birds in the centre of the group are insulated by the birds on the periphery. Also, you will see birds standing on one leg with their bills tucked under their wings so as to minimise the heat loss.

Waders also have another adaptation to prevent heat loss via their legs. The arterial blood vessels carrying warm oygenated blood from the body lay close to the venous blood vessels returning cold blood from the legs. This means that the cold returning blood is heated by the outgoing warm blood and the total heat loss to the body is minimised. The feet of waders are often close to freezing all the time in icy conditions with no adverse affect to the bird (or its feet!).

When the tide recedes these waiting waders wake up and busily start foraging in the mud for food, to replenish the energy stores. The small snails, shrimps, worms and molluscs are abundant on the Basin all winter - another reason they like being here.

The wigeon (small colourful ducks) have come to escape the Scandinavian snows and are quite happy grazing the wet and marshy margins of the basin for seeds, shoots and roots. The recent rain and flooding are, if anything, a great advantage to them as more fields are flooded and hence more plant material is floating around waiting to be picked up.

The eider ducks are here all year round and find the supply of mussels and cockles more than enough compensation for any adverse weather conditions. Both species of duck can fluff up their feathers to help conserve heat when the temperature drops.

The Basin is also a good place to see other ducks like the elegant pintail and the stocky shoveler, which have been seen in sizeable flocks of 80-90 recently.

So we should not bemoan the recent weather, but relish the fact that it brings so many beautiful birds to the Basin where they can be easily seen and admired.