Header image: Juvenile bittern, approx. 35 days old, at RSPB Middleton Lakes, Credit: Mark Smiles
Bitterns have successfully raised young in the West Midlands for the first time in more than a century. RSPB England’s Richard Morris explores how a species at the brink of extinction in the UK only two decades ago is continuing to bounce back.
Timid, highly secretive and well camouflaged, they quietly slink through their favoured reedbed territories. Yes, bitterns can be tough customers to spot. Between January and April, you’re actually more likely to hear this elusive bird than see it. Male bitterns have a distinctive booming call which they use to establish territories and attract mates. It’s a deep, resonating sound that has been known to travel as far as five kilometres, earning the bittern the title of Britain’s loudest bird.
Go back just a couple of decades and you’d be hard pressed to see a bittern or even hear the males’ wonderful booming anywhere in the UK. They were considered extinct as a breeding species in the UK by the 1870s, and despite a resurgence in the breeding population during the 20th century, by 1997 bitterns were once again at the brink of extinction with only 11 males left.
Conservation groups, including the RSPB, took swift action to safeguard the remaining population by restoring reedbeds as part of EU-funded projects and ensuring legal safeguards through the creation of Special Protection Areas (SPAs). Below are just some of the success stories that have unfolded at RSPB reserves across England this year. They show just how quickly a species close to extinction can bounce back with the right conservation support.
At RSPB Middleton Lakes, bitterns have successfully raised five young, marking the first recorded breeding success of this species in the West Midlands for more than 100 years. The last known breeding record is from Sutton Park in 1886, however, this record has been labelled unreliable.
Photo: Three juvenile bitterns in a nest at RSPB Middleton Lakes, Credit: Mark Smiles
The rare, heron-like birds normally nest in large reedbeds. Yet incredibly, not one, but two female bitterns chose to nest in a small section of restored reedbed at the RSPB Middleton Lakes reserve, allowing visitors to enjoy fantastic views of this normally secretive species.
Kate Thorpe, Site Manager at RSPB Middleton Lakes, said: “We were delighted to hear our first ever booming bittern on the reserve in March and have been monitoring the site to see if it found a mate. We were amazed when we realised we had two successful nests in the restored reedbed – one on either side of the county borders. It really goes to show the impact good habitat management can have for threatened species. The work our expert staff and dedicated volunteers have done to bring these birds back to the reserve is incredible.”
RSPB Middleton Lakes is one of the charity’s newest reserves and in just 14 years has become regionally important for overwintering wildfowl including tufted duck, teal and shoveler. SITA – now Suez Community Trust (via the Landfill Community Fund), the Environment Agency and the National Lottery Heritage Fund’s Tame Valley project have all supported work to make a better home for nature at the former sand and gravel quarry.
Central to habitat restoration plans at Middleton Lakes has been the creation of a six hectare reedbed. Willow scrub was removed and the area reprofiled before volunteers planted 10,000 reed plugs brought in from RSPB Langford Lowfields, Nottinghamshire. The reedbed pool has provided the perfect nesting habitat for this year’s breeding bitterns, while a separate new reedbed on the reserve has become an important feeding area.
Projects to restore and create new wetland areas have taken place at several RSPB sites in recent years and the work is paying dividends. Bitterns first recolonised the south and east of England, but habitat creation and restoration work taking place across the north of the country is helping the species extend its range.
Photo: Bittern above RSPB Burton Mere Wetlands, Credit: Andrew Wallbank @atwallbank (Twitter)
RSPB Burton Mere Wetlands on the Dee Estuary near Chester attracted a pair of breeding bitterns for the very first time this year. Excitement began with the arrival of a booming male in spring and visitors were soon treated to plenty of feeding flights across the reserve. As well as being an incredibly positive sign for future breeding, the bitterns’ arrival is a testament to the health of the reserve’s reedbed habitat, which was planted from scratch less than 15 years ago.
An incredible six booming males were heard at RSPB Leighton Moss near Carnforth this spring – the largest number recorded on the reserve since the 1990s. Ongoing work to create new wetland habitats and restore the site’s existing reedbeds has also led to bitterns nesting on one of the reserve’s satellite sites for the very first time. Monitoring of feeding flights suggests as many as four nests could prove successful.
Photo: Bittern in flight at RSPB Leighton Moss, Credit: Jarrod Sneyd.
At RSPB St Aidan’s near Leeds, four booming males were heard this season and four nests have been confirmed on site – the highest number of ‘boomers’ since 2014 and the highest number of nests ever.
Nearby, at RSPB Fairburn Ings, staff and volunteers recorded two booming bitterns this season, and ongoing sightings have raised hopes of a successful nest. Once home to the largest colliery spoil heap in Europe, Fairburn Ings has been transformed into a home for nature. The mix of wetland areas, grassland and woodland now attract some of the UK’s rarest and most beautiful wildlife including bittern, bearded tit, Cetti’s warbler, little egret and spoonbill.
At RSPB Dearne Valley – Old Moor, south east of Barnsley, up to four booming males were recorded, along with early regular sightings of a matriarch female on her third season. Reserve staff have confirmed one successful breeding so far, with at least two juvenile bitterns.
Photo: Female bittern flying over RSPB Old Moor, Credit: Gerald Lax
RSPB Ouse Fen near Cambridge has also enjoyed a record-breaking year, with 12 booming bitterns on site in 2021. The reserve is part of an ambitious 30-year landscape-scale conservation scheme to covert a working sand and gravel quarry into a wildlife-rich wetland habitat that will cover an area equivalent to 980 football pitches by 2030.
Since Ouse Fen’s first bittern arrived six years into the project, their population has continued to increase with the expending wetland landscape. Some of this year’s boomers have even been recorded on the most recently restored 80ha part of the site which only transferred to the RSPB in June. Nearby RSPB Lakenheath Fen equalled its best-ever year for booming bitterns with 11 recorded during the season.
Photo: Bittern in the reedbed at RSPB Lakenheath Fen, Credit: Dave Rogers.
A total of three ‘boomers’ were heard across RSPB reserves in the Mid-Yare Valley, Norfolk, with one confirmed successful nest. In Suffolk, at RSPB Dingle Marshes and RSPB Minsmere, 10 booming males were recorded earlier this year and there are nine confirmed nests across both sites.
At RSPB Dungeness in Kent, staff and volunteers carry out extensive habitat work each winter to help create the right conditions for bitterns. Their efforts are paying off as six booming males were heard at the reserve this year, believed to be a county record.
Meanwhile, across Somerset, a total of 34 male bitterns were recorded this year – 16 of them at RSPB Ham Wall near Glastonbury. Other boomers were heard at the RSPB’s West Sedgemoor and Greylake reserves, and at Natural England and Somerset Wildlife Trust reserves.
In celebration of the bittern’s successful fight against the odds to recolonise the UK, it was named RSPB England’s Bird of the Decade in January 2020. You can read Beth Markey’s blog post to find out more about this species’ history and the remarkable turnaround in its fortunes.
Have you been lucky enough to hear a booming bittern this year, or perhaps catch sight of a feeding flight? Let us know on social media by using the hashtag #RSPBboomingbitterns and tagging @RSPBEngland