It is not temperature which determines when birds come into breeding condition but the increasing hours of daylight.

Obviously, birds have never heard of Valentine’s Day but this is the time when the days start to get longer.

It is this increasing amount of light which triggers the bird’s hormones.

In recent years birds in towns have tended to breed earlier than those in the country. This is obviously due to the use of the street lights.

Two of our common breeding birds are the song thrush and the mistle thrush. With practice it is not difficult to distinguish between the two.

The mistle thrush (turdus viscivorous) measures 10½ inches from beak to tail. The song thrush (turdus philomelos) is only 9 inches long.

The mistle thrush has a sandy grey back, long wings and its tail has its outer feathers lined with white, these are obvious in flight. The song thrush on the other hand has a brownish back and a much shorter tail and with no white on the outside of the feathers.

The spots on the breast of the mistle thrush are very rounded whilst those of the song thrush are more streaky. In flight, the song thrush has patches of orange under the wings.

The nesting patterns of the two species are also very different.

The mistle thrush sites its nest in the fork of a tree and can be up to 30 feet above ground. The nest is untidy and the clutch of 4-5 eggs have a pale bluish-green colour with blotches of dark brown.

The song thrush sites its nest in low bushes. It is much neater and is lined with mud. The 4-5 eggs laid within are a beautiful sky blue and spotted with black.

Between now and mid-May is the time to see the thrushes at their best.