Best year for bitterns for 130 years in Britain

30/08/2008 11:11:32 August 2008. The shy bittern, once extinct in Britain, has had its best nesting season for at least 130 years, according to an RSPB and Natural England survey.

75 booming bitterns
Surveyors, listening for the male bittern's distinctive ‘booming' song, recorded 75 male bitterns in English reed beds, an increase of 47% on 2007's figures and a great improvement since 1997, when the UK population plummeted to a recent low of just 11 booming males, all in England. The number of English counties hosting booming bitterns has also increased to 10, rising from eight in 2007 and four in 1997.

Dr Mark Avery, the RSPB's conservation director, said: "The bittern has suffered an ill-fated history in the UK, having endured extinction once and having been on the verge of extinction again in the late 1990s."

Extinct in UK for 25 years
Although currently confined to England, the bittern was formerly widespread across the UK, where it has endured a boom-and-bust history. In 1886, the bittern stopped nesting in the UK, after drainage of wetlands, and persecution pushed the bird to extinction. Bitterns recolonised the UK in 1911, when birds were found breeding again in the Norfolk Broads.

Dr Mark Avery added: "We weren't prepared to accept a second extinction of the bittern, so we launched a rescue bid to keep the bittern as a British bird. This bid has been so successful that a wide range of other wildlife has benefited too. There are too many threatened species in the world and the turning around of the UK's bittern population shows what can be achieved with a combination of practical determination, proper research and appropriate funding."

Bittern in reed beds. Copyright Andy Hay (rspb-images.com)

Benefit of wet winter
Researchers believe this year's bumper population is directly linked to the very wet winter, which provided ideal feeding conditions for female bitterns, allowing them to get into breeding condition. Overall, the bittern population is increasing because of large-scale recreation and management of reed beds.

Dr Pete Brotherton, Head of Biodiversity for Natural England, said: "This year's figures are a fantastic achievement and show that we can bring species back from the brink of extinction. You would probably have to go back at least 130 years to find a better year for this booming bird."

Part of this bittern rescue package focused on identifying the reasons behind the bird's decline. Research showed that the bittern's future in the UK is entirely dependent on continued efforts to manage and recreate reed beds - the bird's principle watery habitat.

Extend the range
"Despite our success, there's still much more to do. We are working to halt the loss and fragmentation of the country's wetlands and to create new ones," continued Dr Brotherton. "We know bitterns can thrive on coastal and inland freshwater wetlands, and we are confident that we can extend its range still further so that more people can enjoy its distinctive booming call."

Reed beds drying out
One of the key concerns with the UK's bittern population in the 1990s was that reed beds were drying out, preventing the bird from finding enough food. Two massive projects involving funding from the European Union's Life Fund has helped to restore or recreate reedbed sites making them more suitable for bitterns.

East Anglia - Suffolk and Norfolk
East Anglia is still the stronghold of the UK bittern population. But, here a high proportion of the bitterns using freshwater reed beds along the coast are threatened by rising sea levels. Conservationists hope that the spread of the bittern, including to other parts of the UK, will help to give the bittern a more secure future, away from more vulnerable sites.

The strongholds of the UK bittern population are Suffolk and Norfolk, with the counties hosting more than two thirds of the overall numbers of booming males. With 10 booming males, Cambridgeshire also hosts a sizeable part of the UK bittern population. Lincolnshire hosts six booming males, while East Yorkshire, Somerset and Kent held two booming males each, while Lancashire, Hertfordshire and Cumbria each held a single booming male.

The Bittern Monitoring Programme is jointly funded through Action for Birds in England, a conservation partnership between Natural England and the RSPB.