Tuesday 4 March, 2008

SEA-LEVEL RISE THREATENS BITTERN’S CONSERVATION SUCCESS

The bittern – one of the UK’s greatest bird conservation priorities – will have an uncertain future in Britain if more is not done to protect this wetland bird from the ravages of climate change and sea level rise.

The UK bittern population – which is currently growing following near collapse in 1997 – is heavily dependent upon a stronghold in freshwater reedbeds along the Suffolk coast. However, delegates at a conference today [note 3] will hear how these sites are vulnerable to sea-level rise, once more putting the future of this bird, and other rare reedbed wildlife, in jeopardy in the UK.

Dr Mark Avery, the RSPB’s Conservation Director, said: “The UK bittern population is heavily dependent on young birds being produced at a few sites on the Suffolk coast, especially the RSPB’s Minsmere reserve. Alarmingly, all of these freshwater sites are highly vulnerable to flooding by seawater as sea levels rise.

“Bitterns provide a valuable test case to develop our understanding of how to help wildlife adapt to the threats imposed by climate change, giving us an early warning of the fate that may await the rest of our native wildlife. If we fail the bittern, what hope is there for other wildlife in the future?

“Together with our partners such as Natural England, we must re-double our efforts to make existing reedbeds as suitable as possible for threatened reedbed wildlife like the bittern. In addition, a substantial area of new reedbed will urgently need to be created away from the coast, and the threat of climate change-driven, sea level rise. We know it can take at least ten years for a newly created reedbed to support nesting bitterns; but don’t know how long existing sites will be able to survive against the ravages of climate change.”

The current success of bitterns on the Suffolk coast is in contrast with those on the north Norfolk coast where, in 2007, there were three ‘booming’ males, but no nests with chicks.
Rising sea levels mean the long-term future for bitterns in the Broads remains uncertain. Here there were 10 booming males and six nests in 2007, though productivity (young produced) was uncertain, probably poor.

While the success of bitterns on the Suffolk coast at producing young points to a need to protect these for as long as possible, conservation bodies also have an eye on the future.
RSPB Lakenheath Fen in Suffolk is the first major wetland creation project in Eastern England, and shows it can take 10 years or more to create a wetland suitable for bitterns. Britain’s biggest reedbed is being created over the next three decades at the Hanson-RSPB Wetland Project at Needingworth in Cambridgeshire, and should attract up to 20 pairs of bitterns.
More reedbeds will be needed sooner to offset likely losses from sea level rise in East Anglia, says the RSPB. The Environment Agency is actively looking for new sites to replace those being lost in Suffolk and elsewhere.

Sir Martin Doughty, Chair of Natural England said:  “We successfully managed to stave off national extinction for a second time in the 1990s and last year we recorded over 50 booming males. These recent gains are clearly still at risk, especially with the threat of sea level rise, tidal surge and coastal erosion.

“At Natural England, we are working with the Environment Agency and others, to create alternative reedbeds inland, for example, through the Great Fen Project. The National Nature Reserve at Walberswick, is another important site for bitterns - one of a number of sites where Natural England staff support and monitor the fragile bittern population. 
“Natural England supports a more sustainable approach to managing the coastline not only for bittern but also for the entire range of wildlife on the coast. We want to see rapid progress towards managed-realignment in both coastal and fluvial environments, including the creation of managed washlands and wetlands in appropriate locations. The future lies in creating more sustainable reedbeds inland away from the eroding coastline. We need to take urgent action now.”

Extinct in Britain between 1886 and 1911, the bittern reached a second low point in 1997, when the bird’s population dropped to 11 males.  However, 10 years on, surveyors from the RSPB and Natural England recorded a minimum of 51 male bitterns across 33 sites, giving encouragement to everyone involved with the conservation of this bird. Last year’s total was a 16 per cent increase on last year’s figure of 44 males, and only four behind the recent record of 55 males in 2004.