A robin is ringed to help keep track of it.
Julian and Angela Langford, at British Sugar's Allscott Sugar Factory, have been ringing birds for the past 44 years and have discovered species are flocking to the site from as far as Siberia and Senegal.
The pair have ringed 100,000 birds of 121 species at the site with more than 130 foreign ringed birds being caught, including Siberian bewick swan, Polish curlew sandpiper, Maltese little stint and Moroccan lapwing.
Longevity records includes a 30-year curlew, a snipe of 16 years and a 16year-old swift.
Mr Langford has led up to 6,000 members of the public on birdlife visits since 1961.
Management of the site, which consists of 17 manmade lagoons, is taking place with six reed beds planted. When the ringing scheme started there were no reed warblers. There are now 100 pairs every year.