The UK’s loudest bird has had a bumper breeding year after previously being driven to extinction in the country.
Bitterns became locally extinct in the 1870s due to persecution and draining of their wetland habitat for agriculture. Now the RSPB has revealed that thanks to conservation work, the bird, which has a distinctive “booming” call, has had one of its most successful breeding seasons.
Last year, the secretive member of the heron family bred successfully for the first time at RSPB Saltholme nature reserve in Teesside – their most northerly breeding record. Although most of the records are in England, with some in Wales, bittern were once found in Scotland and Northern Ireland, and there is hope that they will once again have a presence there.
Conservationists counted 228 booming males during the last breeding season, one of the most successful years to date. The wetland-dwelling birds depend on reedbed habitats, where they move, camouflaged, to hunt fish, insects and amphibians.
The males are easiest to count as you hear them before you see them; they are the loudest bird in the UK with their far-carrying “foghorn” boom being detectable up to three miles away. Men of the species make this noise in spring to attract female mates.
Bitterns returned to Norfolk, coming over from the European mainland, in 1900, but after their wetlands were drained for agriculture in the 20th century their population dropped again and fell to just 11 males by 1997.
Since then, the restoration of their habitat has caused the species to recover, though it is still amber-listed, meaning it is under threat.
Conservationists continue to try to restore their habitat so they can have a secure future in the UK.
Simon Wotton, an RSPB senior conservation scientist, said: “Many wetlands were drained in the 19th and 20th centuries to make space for agriculture, leaving the bittern fewer and fewer places to breed.
“One of the aims of the bittern work since 1990 was to create and restore suitable wetlands away from the coast – to create safe sites that wouldn’t be affected by the effects of climate change such as rising sea levels.
Rewetting these spaces also helps prevent flooding and fights the climate crisis – wetlands are incredible carbon sponges, with coastal wetlands locking in more carbon that forests. A win-win for the nature and climate crises.”
Though there are only a few hundred of them in the country, bitterns can be seen – and heard – in spring at locations including Minsmere in Suffolk, Avalon Marshes, Somerset and the Ouse Fen in Cambridgeshire.
