ALL wildlife takes a real beating during periods of bad weather, especially at times of heavy snow.

Birds suffer particularly badly and many die.

Although it may appear to be a bit gruesome, good naturalists should examine every dead bird they come across.

Some birds will have a ring on their leg. These should be removed and dealt with based on the following information.

Why do we ring birds?

Much has been discovered about birds by watching and counting them but such methods rarely allow birds to be identified as individuals. This is essential if we are to learn about how long they live and when and where they move, information which is vital if we are to help conserve birds.

Placing a lightweight, uniquely numbered, metal ring around a bird's leg provides a reliable and harmless method of identifying birds as individuals. Each ring also bears an address so that anyone finding a ringed bird can help by reporting its whereabouts and details of the possible cause of death.

Some ringing projects also use colour rings to allow individual birds to be recognised while they are still alive.

It helps researchers if the ring itself is sent back to them because the bands (as they are called in North America) are made of an alloy. Those who make the rings need to know how long they can survive out in the wild and exposed to all sorts of weather.

How are birds caught for ringing?

About 20 per cent are ringed as chicks in the nest. This method is particularly relevant in seabird colonies such as Arctic terns. This species travels more miles in a year than any other species and this information can only have been obtained from returned rings.

Returned rings also provide information about how long individual birds may live. Another frequently used method is to catch fully-grown birds in what is known as mist nets. A mist net is made of a fine mesh suspended between poles and designed to catch birds in flight.

This method is very effective but birds can only be removed safely from mist nets by experienced ringers who have received special training.

Does ringing affect the birds?

The answer to this question is no. It is essential that birds are not unduly affected by the fitting and wearing of a ring. If they were, ringing would fail to tell us how normal birds behaved.

Many studies have shown that birds ringed during the breeding season quickly return to incubating eggs or feeding chicks once they have been released.

Long distance migrants continue to travel thousands of miles between breeding and wintering grounds. Birds will not be affected as long as banding is carried out by skilled ringers who show the utmost consideration for the birds' welfare.

It is not surprising that ringing has little effect on the birds because, relative to the bird's weight, a ring is similar to a wristwatch which we all wear today.

Our ringing scheme is organised by the British Trust for Ornithology (BTO). Around 800,000 are ringed in Britain and Ireland by around 2,000 ringers, most of whom are volunteers.

On average fewer than one out of every 50 birds ringed is subsequently reported to the BTO, so each and every report of a ringed bird is of value.

If you would like to join the British Trust for Ornithology (which produces a magazine and lots of scientific books), return a ring or learn to become a ringer, you may write to the organisation at The Ringing Unit, British Trust for Ornithology, The Nunnery, Thetford, Norfolk, IP24 2PU. Telephone 01842 750050; fax 01842 750030; e-mail ringing@bto.org; web site http/www.bto.org