Britain’s loudest bird makes roaring recovery

Thursday 24 March 2022

  • Bitterns, the loudest bird in Britain, have had another record-breaking year with 228 booming males counted in 2021.
  • Bitterns went extinct in the UK in the 1870s due to persecution and draining of their wetland habitat for agriculture.
  • Restoration, recreation, and protection of wetlands, which also act as natural carbon sponges and help prevent floods, has boosted their numbers.

Bitterns, Britain’s loudest bird, have had another record-breaking year with 228 booming males counted in 2021, up from 209 in 2019, according to new survey results from the RSPB and Natural England (recording in 2020 was affected by the coronavirus pandemic). This member of the heron family went extinct across the UK in the 1870s due to a combination of over-hunting for food and draining of their wetland homes for agriculture. Bitterns returned to Britain in the early 20th century, and restoration of wetlands has allowed their numbers to more than double in a decade, with over half on RSPB reserves.

Bitterns are well-camouflaged, shy birds that like to hide in reedbeds, so the most reliable way to count them in the breeding season is to listen for the male’s booming foghorn call which can be heard from three miles away. Numbers were very low when the first annual surveys began in 1990 and in 1997 there were only 11 males across the whole UK, leaving them on the edge of a second national extinction.

A key part of bringing bittern numbers back up was restoring, recreating, and protecting their wetland habitats. Many wetlands were drained in the 19th and 20th centuries to make space for agriculture, leaving the bittern fewer and fewer places to breed. 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.

Simon Wotton, RSPB Senior Conservation Scientist, said: “The bittern’s recovery shows how quickly nature can bounce back when given the chance – and we all benefit from creating healthy spaces for wildlife. People get such joy from hearing the bittern’s mighty foghorn-like song, and their wetland home also protects people from flooding and helps to soak up carbon. It’s a win-win for wildlife and people, and we hope that one day the boom of the bittern will be heard around the UK once more.

“I want to say a huge thank you to all the volunteers, conservation site staff, and landowners who monitored sites in 2020 and 2021 during the Covid-19 pandemic. Without them and everyone who uploaded their recordings to online sources we would have lost invaluable information about these endangered and magnificent birds."

Although bitterns are still a rare bird, there are some great places to experience them first-hand including these RSPB reserves:

Ouse Fen, Ham Wall, and Lakenheath Fen were all created during the mid-1990's to help boost bittern populations as part of one of the Bittern EU LIFE projects.



  1. The RSPB also drew on data from BirdTrack and eBird to help collate records of booming bitterns around the UK in 2020 and 2021.
  2. The RSPB coordinates Bittern monitoring across the country each year, through the Bittern Monitoring Programme, an Action for Birds in England (AfBiE) project. Under the AfBiE agreement, a conservation partnership between Natural England and RSPB, it is proposed that there will be a periodic full survey if the annual monitoring starts to suggest a rapid decline in the population.
  3. Bitterns are just one of the species found to be thriving on RSPB reserves and beyond. The RSPB Ecology Report 2021 reveals how a vast range of wildlife has been faring on the charity’s 222 nature reserves across the UK. To read more about the highs and lows of not just avian wildlife but flora, fauna and mammals on RSPB sites too, please download the full report.

Last Updated: Friday 25 March 2022

Tagged with: Topic: Birds Topic: Conservation Topic: Reserves Topic: Bittern Topic: Wetland