Just at the time when young Blue and Great Tits were demanding vast amounts of food this spring, the weather turned cold and wet, cutting off the normally abundant supply of insects needed to rear 6-12 boisterous young. In the nest boxes I checked, 75% of the young were either dead or dying.
Coal Tits, one of the tit families regularly visiting your bird table, breed mainly in conifer forests. Conifer trees have little or no natural holes in them so Coal Tits have adapted to nest in holes in the ground. Disused mouse and vole holes are their favourite. Holes in the ground are notorious, as we know when it is wet. Coal Tit nests are very difficult to monitor, but I guess the mortality this year will be even greater than with the Blue and Great Tits.
Every few years, there is what is known as a 'Mast Year'. Mast years are when beech trees produce an abundance of fruit and this is one of those years. Beech nuts, as they are better known, are the natural winter food for everything from mice to pgs and tits to crows - the bigger ones scratching the leaves and snow aside to leave pickings for all.
So if you find a shortage of birds in your garden this winter it is partly due to a very poor breeding season but some absentees are just feeding on the natural food God has provided. But don't despair - it is a natural happening. Tits have big broods for a reason - in one good breeding season, the deficit will be corrected.
For over 30 years I have been collecting data to be used in research on the effects environmental poisons are having on birds of prey, which has been quite an eye-opening experience. Birds of prey are at the end of the food chain, much the same as ourselves. Being more food specific than we are makes them a good species to monitor to find out how healthy our planet really is. The staple diet of hawks, falcons and buzzards is small mammals, birds and big insects, which in turn need a good source of food for themselves.
A little poison in a chaffinch or a mouse might not be detected or kill it straight away, but the cumulative effect on the predator is devastating. Finding out how healthy our chaffinches are through sparrowhawks might seem a strange route, but it is accurate and holistic.
Buying bird feed from a reliable source is very important and not to be taken lightly. José and Martin Guerrero are members of several environmental organisations and spend a lot of their spare time doing voluntary work protecting the environment. José and Martin make sure the bird food they sell is safe, so buy from them with confidence, from people who understand and care. Give small birds the right food and we are on the right road to redress the situation, by getting to the real cause of the decline in song birds.
Colin
Colin Jewitt was formerly the General Manager of Ladycross Stone Company at Slaley, in Northumberland. Colin's on-going work in developing the worked-out areas of Ladycross Quarry into a nature reserve led to him being awarded the national award of Countryman of the Year, 1998. He now lives in Spain, leading wildlife and birdwatching breaks.