Posted 5th Jun 2018 by Peter Byrne
For the first time in a decade, bitterns are breeding at RSPB Leighton Moss in Silverdale
The welcome news comes after new methods for managing the nature reserve were introduced four years ago.
An unusual cousin of the grey heron, bitterns rely on reedbeds (now a rare UK habitat) to live in, with Leighton Moss being the largest one in North West England.
Jarrod Sneyd, Site Manager at Leighton Moss, said: "Leighton Moss has always been synonymous with bitterns. Whilst we have consistently had them living here throughout the seasons, for the last 10 years they have sadly not been breeding. The reasons why are complex. Leighton Moss is an old reedbed, having formed after the First World War and aging reedbed tends to be quite dry. Bitterns like young, wet reedbeds where they can catch fish, so RSPB staff and volunteers spend a lot of time managing the site in a way that halts its aging process, and creates the conditions that bitterns and lots of other wildlife need to thrive."
Reedbed is a very important habitat to conserve in the UK, as much has been lost due to drainage for agriculture and development.
By the late 1990s, bitterns were virtually wiped out in the country, due to the loss of this habitat. At this point, Leighton Moss was one of only a few sites where the birds were still clinging on. There were only eleven booming male bitterns left across the country, with three of them at Leighton Moss, and the majority of the others in East Anglia.
Since then, the RSPB has been working alongside other nature conservation organisations to save the species and it's been predominantly successful. 166 males were recorded in 2017 with strongholds proving to be the Avalon Marshes in Somerset and the reedbeds of East Anglia. However, this success was not being repeated at Leighton Moss.
Jarrod added: "The traditional methods that have always worked in the past when managing Leighton Moss for bitterns, had recently stopped being so effective, which is why these birds sadly stopped breeding here. Lots of research went into how we might be able to improve the reedbed for bitterns once more. Our expert ecologists and wardens embarked on new, experimental methods of managing the reedbed four years ago, including digging out parts of the reedbed, temporarily drying out some areas and introducing deer management. This has encouraged the reed and other plants to grow in areas where they were struggling. It’s still early days but we’re delighted with the results so far. The reedbed has responded really well to the changes and the fact we have a bittern nest once more is a really encouraging sign."
The bittern populations are monitored by recording the number of 'booming' males - this booming is the unusual song of the male birds, with the deep sound like blowing over the top of a glass bottle.
When they fully boom, a male can be heard for several kilometres.
Jarrod continued: "We’ve had a booming male over the last decade, but he would fail to work up to a full boom or stop early in the season and there was no sign of any breeding females. This year we were excited to hear a male properly booming in the reedbed, along with sightings of a female. Our dedicated team of wardens and volunteers have been out all spring, listening for booming and watching the female’s activity. They have been rewarded in the past couple of weeks by views of a female regularly going into and out of the same spot on the reserve – a sign that she is taking food into a nest for her chicks. We are absolutely thrilled!"
Visiting the site could see you rewarded with the sight of a female bittern from the Causeway hide, accompanied with a variety of other special wildlife which resides at the reserve, such as the breeding marsh harrier, a reedbed specialist bird of prey.
Image courtesy of RSPB Images / John Bridges