This is the first in a series of monthly articles which will delve into the treasure-trove of information in Bird Atlas 2007-11: The Distribution and Abundance of Breeding and Wintering Birds in Britain and Ireland. Once the final data are entered – deadline 31 January – and verified, we’ll be able to show up-to-date maps, changes in distribution and the gains and losses across Britain & Ireland. There will be plenty to keep people interested as we move towards final publication in August 2013.
If there is one species that will star as a success story it’s the Little Egret. The map alongside shows the winter records between 2007-08 and 2010-11. It’s still provisional, as we await the completion of the verification process, but the map is hugely different to the last winter atlas , when there was a grand total of one record in the three winters between 1981/82 and 1983/84.
We cannot show the map for the breeding season yet, as there is still some work to do to clarify some of the possible and probable breeding reports – a reflection in just how widespread the species has become and how much individuals move around. During the breeding season individuals can be found in suitable feeding areas which are well away from the closest colony and these are the records that need to be considered more carefully. This is one of the many challenges that are being faced by local atlas organisers and recorders, as well as by the atlas authors, as they interpret millions of rows of data.
Little Egrets are now commonly recorded as part of the BTO’s Heronries Census, augmented by other counts collected locally. They provide a bit of a bonus to observers who have been counting nesting herons for decades. The first confirmed breeding record was in 1996 in Poole Harbour, Dorset, with Ireland’s first the following year. By 2006 Little Egret was well established with over 500 pairs confirmed breeding in 60 different colonies as far north as North Wales. In 2009 over 800 pairs bred (see figure) and the WeBS counts for that autumn totalled around 5,000 individuals on our estuaries and waterways.
Atlas projects only come around every twenty years but we shall be able to continue to monitor Little Egret numbers thanks to WeBS. Hundreds of birdwatchers take part in monthly counts on estuaries, inland water-bodies and local ponds and gravel pits, to monitor waterbirds. Little Egrets have been added to more and more local lists over the last two decades, now being found on nearly 400 sites, with the Wash WeBS counters leading the way, providing autumn totals of more than 600.
Ringing has also thrown up some interesting information on young Little Egrets from UK colonies. Birds ringed as nestlings in the UK have been reported as far south as Spain and the Canary Islands. A bird ringed as a nestling in Kent in 2001 was later found freshly dead in Norfolk in 2010, in the process becoming the oldest known Little Egret in Britain and Ireland at nine years, six months and twenty-five days.