What a difference a day makes. From near freezing for several days up until 13th February the temperature rose rapidly by sixteen degrees on Valentine's day.

So, appropriately perhaps, the local songthrush and chaffinch which had fallen silent during the cold snap burst into full song again, cheered by the mild day. Blackbirds joined in and nuthatches began their far-reaching piping calls.

According to St. Valentine, February 14th is traditionally the day on which birds choose their mates but many species including ducks and robins had already paired up. Members of the crow family mate for life as do swans (pictured) which can now be seen 'necking' and, beak to beak, form a perfect heart shape.

Territorial disputes figure widely now and of course, birdsong is not, as was believed in Victorian times purely for our benefit but a crucial attempt to hold territory and attract mates.

On a beautiful mild sunny day at the Wetland Centre I watched with amusement two male dabchicks endlessly chasing one another across the water uttering very loud calls for such small birds. For us, the dawn chorus is nevertheless a wonderful by-product and musical prelude to spring whatever birds use it for.

With current topsy-turvey temperatures changing rapidly from mild to bitterly cold days, the birds seem to delay the morning chorus for an hour or so from first light and await the rising sun, or, if very cold, stop singing altogether.