(Continued)

By early February we'll be aware of a change in the light and an increase in the volume of bird song. The mistle thrush will have started in January, in fact, and the robin and wren sing throughout the winter; but they will now be joined by the dunnock, great tit, blue tit and song thrush; and the greenfinch and chaffinch will be tuning up too. The different species keep to quite a strict calendar of birdsong and I have added a chart to illustrate this at the end of the article. The timing seems to be controlled by both the light and the temperature so it varies systematically in different parts of the country. By the first week of March in Thurlow, at any rate, the blackbird, skylark and yellowhammer will have joined the chorus; and then, in mid-March, by a yearly miracle of long-distance migration the first of our summer visitors can be heard singing sweetly down by the river - the chiffchaff.

That heralds a stream of arrivals from the south, again in a regular sequence which goes something like this: chiffchaff 20 March, willow warbler 8 April, blackcap 10 April, swallow 12 April, house martin 20 April, cuckoo 21 April, whitethroat 4 May, swift 5 May, turtle dove 6 May, and finally the spotted flycatcher 20 May. It isn't always quite so precise, of course, but it's usually there or thereabouts. Interestingly, I've noticed that in recent years the dates are getting a few days earlier. Is that global warming? Doubtless the authors of Thurlow 3000 will be able to tell us! The other thing we must all have noticed is how many fewer there are of many species, especially the seed-eaters like skylarks, buntings and even the once-abundant sparrows, all of whom have suffered the combined effects of herbicides, pesticides and 'improvements' generally. Thurlow 3000 may also, I fear, document a blander and bleaker world if we do not take a larger view of what constitutes progress.