Among the people reporting early nesting to the BTO was a garden birdwatcher in Kent who witnessed blue tits fledging before the end of January.
The man was going to clean out his nestboxes when he heard a noise from inside one of the boxes and on opening it found a brood of half-naked blue tits. He wrapped the box in bubble-wrap and the birds survived the cold snap. In another incident, two great tit eggs were found in a nest box in Lincolnshire.
Despite these exceptionally early nesters, most birds won't start until later in the spring, so there's still plenty of time to put out nestboxes. The British Trust for Ornithology
's 'National Nestbox Week' kicks off on 14th February and coincides with the publication of a new book, The BTO Nestbox Guide
, which tells you all you need to know about making nest boxes.