Sir David Attenborough’s new BBC series Wild Isles has been showcasing the wildlife and wild places across the UK and this new series, as we would expect, reveals the surprising and dramatic habitats that exist right on our doorstep.

The five-part series is a unique collaboration between the RSPB, WWF and The Open University, working with the BBC and Silverback Films.

The RSPB, which works to protect habitats and wildlife around the country, has fascinating snippets of interesting information to share with visitors.

So, ahead of the Easter holidays, I caught up with Beth Fox, Visitor Experience Manager at RSPB Leighton Moss, Lancashire, to be enlightened about its success in encouraging a bird that has an impressive claim to fame.

A member of the Heron family, Beth tells me that the bittern population, well the males of the species, has begun delighting visitors from across Lancashire and urban cities such as Manchester, Blackpool and Lancaster, because they have a distinctive call known as a boom.

Since the RSPB took over the site in 1964 it has been encouraging bitterns to the largest reedbed habitat in the North West, as it supports species like the bittern which is perfectly camouflaged among the reeds.

“They are really difficult to see but they make this unusual far carrying loud low pitched boom which can be heard up to three miles away,” Beth said.

It is a noise that only the males make when they seek out their territory ahead of the breeding season. See the video below.



“We are in the peak booming season now which started this month and continues through until the end of May. The males have already started warming up and we can hear them making grunts, coughs and wheezes but it is when they are in full boom that they make their impressive sound.”

Beth explains that the best way to describe the boom is to blow on the top of a glass milk bottle.

Remarkably, due to a loss of habitat in the 1900s pre war era, Leighton Moss was called the Golden Bowl. It was prolific for cereal crop in part, because it was so marshy with a big build up of peat, meaning the land was repurposed for food production, which ultimately let to the drainage of wetlands, and coupled with hunting, the bittern went into decline in the UK.

By 1997 there were only 11 booming males left in the whole of the country but due to RSPB investment rejuvenating the reedbed over recent years it has created the perfect conditions to halt the decline.

The numbers are rising and, according to Beth, 228 booming males were counted in 2021. There were six males and four nests in 2022 and this year there are thought to be seven males that have begun booming.
I am intrigued. How can the RSPB collect such detailed and specific information as we have already established the bittern is well camouflaged?

Beth explains: “Our wardens monitor the birds just by listening to them and sometimes using sonographic information to determine how many males are on site and by undertaking co-ordinated listening sessions mapping where the booming birds are heard.”

Leighton Moss is easy accessible on the Manchester Airport to Barrow in Furness railway line and it is only 250 metres away from the station and Beth enthusiastically tells me that if you travel by green transport entry is half price.

“Urban nature experiences are closer than you think, and we’re delighted to see visitors travelling here by train to come and hear what Britain’s loudest bird sounds like for themselves. It’s fantastic to see new nature lovers arriving at the reserve so early in the season. From our nine-metre sky tower you might even be able to spy one of the birds.”

“Along with Morecambe Bay, Leighton Moss is a jewel in the crown of Lancashire, the reserve is a designated Site of Special Scientific interest.”

The sound of bitterns booming is just one of the nature spectacles that can be experienced this spring.