Another record-breaking year for the UK’s loudest bird

It’s been another record-breaking year for Bitterns in the UK with 283 booming males recorded in the latest results from the RSPB and Natural England, a 20% increase from the previous survey and the biggest jump since monitoring began in 1990. 

Bitterns have a checkered history in the UK. Persecution and habitat loss drove the birds to extinction by the late nineteenth century. They returned to Norfolk in 1900 but suffered another drop in numbers to just 11 remaining booming males left by 1997.  

Determined to stop Bitterns becoming extinct once more from the UK, we teamed up with Natural England on a major targeted conservation effort in order to stop the decline.  

Bitterns are dependent on reedbeds and so we set out creating and restoring these wetland habitats, to create the conditions they need to feed and breed successfully. This has been vital to their success – and it’s thanks to our many members, supporters and funders that this vital work has been possible.

Today, over half of the UK’s Bittern population can be found on RSPB nature reserves, with 138 recorded booming. This includes RSPB Minsmere and RSPB Lakenheath Fen, and on the Avalon Marshes, notably at RSPB Ham Wall. Long-term reedbed creation and restoration across these sites have provided the specific conditions that Bitterns need for breeding. 

Booming was also reported from 12 new sites in 2024, demonstrating the significant success these conservation efforts can have in aiding the species’ recovery and bringing Bitterns back from the edge of extinction in the UK.   

RSPB senior conservation scientist Simon Wotton said: “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.  

“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.  

“As valuable reedbed habitat remains threatened by rising sea levels due to climate change, these vital breeding sites continue to provide important refuge for Bitterns and other wetland species. With Bittern previously threatened with extinction, their recovery is a clear example of how dedicated conservation action combined with the right leadership and resources, can help us rise to the challenges we face in this nature and climate emergency.”  

Bitterns are secretive birds and well-camouflaged in the reedbeds. However, males produce an incredible and far-carrying “booming” call when trying to attract a mate. It’s this boom that makes them the UK’s loudest bird. Their remarkable boom can be heard up to three miles away! 

So, to monitor how Bitterns are faring, a dedicated team of volunteers and conservation site teams listen out and record these booming males during spring. Thank you!  

Bitterns are found in England and Wales. Although still a rare bird, there are many RSPB nature reserves across England and Wales where you can listen out for the species, including: 

• RSPB Leighton Moss, Lancashire  

• RSPB Otmoor, Oxfordshire  

• RSPB St Aidan’s Nature Park. Yorkshire  

• RSPB Blacktoft Sands, Yorkshire  

• RSPB Ouse Fen, Cambridgeshire  

• RSPB Minsmere, Suffolk  

• RSPB Lakenheath Fen, Suffolk  

• RSPB Ham Wall, Somerset  

• RSPB Valley Wetlands, Anglesey  

• RSPB Cors Ddyga, Anglesey  

The annual Bittern survey, along with many other species monitoring programmes, are vital for effective conservation. They wouldn’t be possible without the help of dedicated volunteers who give their time for nature.  

 More than 13,000 people volunteer for the RSPB, taking action to make a positive impact for nature and the environment. To find out more about how you can get involved in volunteering with the RSPB to help benefit Bitterns and other amazing wildlife, click here.