Author Barry Yates
There has been a big effort to increase the bittern population in Britain over the last 17 years and it has worked. In 1997 there were just 11 booming males from only 7 sites, but last year there were 104 booming males at 51 sites. This work and the whole history of the species has just been reviewed in a paper in British Birds. Put quite simply they needed more sites and larger areas of fish-filled reedbeds throughout Britain. The review emphasises that this ‘single species’ conservation effort has benefitted a wide range of other wetland wildlife.
In Sussex we have done our bit, Castle Water and other sites have been improved and extended. When the Sussex Wildlife Trust bought Castle Water (a former gravel pit) in 1992 there were no bitterns and very little reedbed, but there was potential and after a few years we had developed some reed fringes and several bitterns were spending the winter here. This then led to our participation in an EU-Life project led by RSPB called Reedbeds for Bitterns, so in 2003 and 2006 we began large scale landscaping and moved 100,000 cubic metres of soil to create shallow water and new ditches where there had been rather boring improved grassland and we put this into the neighbouring gravel pit to make 140 new islands. There is now the potential for 18 hectares of reeds and in the next few months the many strange sounds from the reedbed should include booming (April-June for the last three years) and we are hoping for the first confirmed nesting of bittern in Sussex.
Strange sounds? The specialised birds living in a dense reedbed cannot see their neighbours and so have developed some distinctive noises to communicate – booming bittern, pig-squealing water rail, endless chattering of reed warblers, pinging of bearded tits, explosive bursts from Cetti’s warbler. And this makes all these birds very difficult to count… but we try!
There have been three bittern at Castle Water in the last few weeks, but in the coming cold days they should be easier to see because the fringing ice will force the birds out into the open and extra birds may fly from a very frozen continent to be in our mild waters. Let’s hope the freeze doesn’t last too long and our resident (?) bitterns survive to breed this year.