Once extinct in the UK, and having faced a drop after they did return, the population of bitterns is booming – literally – according to last year’s survey results from Natural England and the RSPB.
In 2024, 283 males were recorded 'booming' across the UK, which is a 20 per cent increase on the 2023 numbers, and the largest jump since monitoring began in 1990.
The booming call of a bittern is an unusual sound, sometimes compared to the noise made when you blow over the top of a bottle, and can be heard almost three miles away. It is only the adult male bird who booms, calling loudly in spring to attract a mate.
Bitterns live and breed in reedbeds on wetlands, where they are elusive and hard to spot – despite their size. To get a consistent population survey method, conservationists count how many males are booming.
Bitterns can call at any time of day during spring, but the best time to hear it is on a still day in the two hours around dawn or dusk.
When numbers of the species declined down to just 11 booming males in 1997, dedicated conservation work took place to restore wetlands, and to create new ones, particularly in locations safe from coastal flooding.
“Wetlands are incredible places for nature and these bittern breeding success stories are a shining example of effective conservation efforts undertaken by dedicated organisations, landowners and volunteers,” says Simon Wotton, RSPB senior conservation scientist.
“It is fantastic to see bittern numbers increasing across the country – notably on RSPB nature reserves – thanks to the hard work of staff to create safe havens for this iconic species. With the arrival of spring, now is the best time to listen out for their famous boom.”
More than half of the UK’s booming bitterns are found on nature reserves run by the RSPB, with notable sites including RSPB Lakenheath Fen (also home to common cranes) and RSPB Minsmere in Suffolk, RSPB Leighton Moss in Lancashire, RSPB Ham Wall in Somerset (also famous for its starling murmurations), and RSPB Cors Ddyga on Anglesey.
Main image: Eurasian bittern wading through shallow channel in reedbed, RSPB Minsmere Nature Reserve, Suffolk. Credit: Ben Andrew (rspb-images.com)
More wildlife stories from around the world
- 16 ancient creatures found encased in amber in remote forests of Myanmar
- Here's why 15 giant birds were just released into Patagonia National Park
- The world's smallest leopard is also one of the Earth's rarest cats
- "Uncharted territory": soft tissue of ancient animal found entombed in volcanic rock near Rome
