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Bittern boom in East Anglian Fens Bittern boom in East Anglian Fens
(about 11 hours later)
One of the UK's rarest birds has been found in the East Anglian Fens for the first time since before World War II, the RSPB has revealed. The numbers of one of Britain's rarest birds, the bittern, have increased in the East Anglian Fens, the RSPB has revealed.
Newly-created habitats are helping the bittern, known for its "booming" call, recover from losing breeding grounds.Newly-created habitats are helping the bittern, known for its "booming" call, recover from losing breeding grounds.
Pairs have been recorded nesting in new reedbeds for the first time, as conservationists attempt to prevent loss of habitat for the birds. Pairs have been recorded nesting in newly-created reedbeds, as conservationists attempt to prevent loss of habitat for the birds.
The rare bird is nesting in more sites in the UK than in any year since 1990. The bird is nesting in more sites in the UK than in any year since 1990.
A privately-owned wetland site converted from farmland in Cambridgeshire has evidence of four nests involving three different breeding females, the RSPB said.A privately-owned wetland site converted from farmland in Cambridgeshire has evidence of four nests involving three different breeding females, the RSPB said.
Climate change
The bittern was extinct in Britain between 1886 and 1911. In the 1990s research found reedbeds were drying out, threatening their survival once again.The bittern was extinct in Britain between 1886 and 1911. In the 1990s research found reedbeds were drying out, threatening their survival once again.
Rising sea levels
But 10 years after the UK's bittern population hit a new low of just eleven males in 1997, the RSPB and Natural England have recorded at least 51 male birds across 33 sites this year.But 10 years after the UK's bittern population hit a new low of just eleven males in 1997, the RSPB and Natural England have recorded at least 51 male birds across 33 sites this year.
The numbers are up from last year's 44 male bitterns and only four behind the recent record of 55 in 2004.The numbers are up from last year's 44 male bitterns and only four behind the recent record of 55 in 2004.
The news that they are nesting in man-made reedbeds is seen as a positive sign as many of their traditional natural habitats are threatened by rising sea levels, the RSPB said.The news that they are nesting in man-made reedbeds is seen as a positive sign as many of their traditional natural habitats are threatened by rising sea levels, the RSPB said.
Rising sea levels threaten to inundate eight freshwater reedbeds, increasing salinity and making them unsuitable for this sensitive bird Dr Mark Avery, conservation director of the RSPB
Dr Mark Avery, conservation director of the RSPB, said: "The spread of bitterns into newly-created reedbeds is a testament to all those involved with habitat creation, especially in the East Anglian Fens.Dr Mark Avery, conservation director of the RSPB, said: "The spread of bitterns into newly-created reedbeds is a testament to all those involved with habitat creation, especially in the East Anglian Fens.
"Reedbeds sites occupied by more than 40% of male bitterns this year are at risk. Rising sea levels threaten to inundate eight freshwater reedbeds, increasing salinity and making them unsuitable for this sensitive bird." "Encouraging bitterns to nest in newly created sites away from the coast helps to buffer these sensitive birds against the impacts of climate change."
Bittern numbers are tracked by listening for the male's "booming" call and more recently by identifying locations of nests with chicks.
More than three-quarters of "booming" males are in East Anglia, with around nine in the North East - mostly in sites around the Humber.