The RSPB Dee Estuary nature reserve is vast and complex, covering over 6000 hectares of varying wetland habitats making it the fifth largest RSPB reserve and the largest protected coastal wetland in the UK. Since 2011, Burton Mere Wetlands has become the much-loved heart of it all, but this series of blogs aims to lift the lid on some of the wilder, lesser known locations we manage.
Owing to its location just the other side of the village from Burton Mere Wetlands, and its much improved accessibility since the 2013 completion of the Burton Marsh Greenway, this part of the estuary has become better known in recent years.
It is actually one of the newest parts of our reserve, managed by us since we purchased Burton Marsh Farm in 2006. This farm had the traditional grazing rights to the inner saltmarsh as it expanded from the sandstone outcrop of Burton Point following the canalisation of the river in the 18th Century, and connected our existing landholding at Parkgate with the developing Burton Mere Wetlands site. Anecdotal reports suggest as many as 10,000 sheep and a small number of cattle were grazed here historically, at a time when the marsh was a lot smaller than it is today. This resulted in a very short, bowling green appearance of the saltmarsh grass which would have been generally poor for wildlife.
Burton Marsh Farm buidings, sheep pens and saltmarsh (Colin Wells)
The farm purchase spurred us to negotiate grazing agreements for the parts of Burton Marsh owned by the Ministry of Defence at Sealand, and Tata Steel at Deeside, increasing our management area of Burton Marsh by nearly tenfold, which still exist today. If you've ever walked alongside the marsh here, you'll have noticed the red and white MOD signs warning of the nearby firing range; the so called 'danger area' covers a large chunk of our reserve, so any work we do here has to be closely coordinated with the the MOD to avoid putting ourselves at risk. This, along with the complex network of tidal pools and gutters, is a prime reason not to venture onto the saltmarsh here!
Burton Marsh looking towards Deeside Industrial Park (Colin Wells)
It's important to note at this point that the Dee Estuary as a whole is a designated Special Protection Area for its bird populations, and the saltmarsh itself is a Special Area of Conservation for its plant diversity. So how do we use grazing to manage the saltmarsh for the benefit of birds and wildlife? These days, the sheep flock numbers around 2000. The key is to achieve the desired grazing level to create the most suitable habitats for the key birds that rely on the saltmarsh habitat.
Overgrazing results in very short grasses that may suit winter wildfowl like pink-footed goose and wigeon to feed on, but are less good for breeding birds like redshank and skylark who need some taller grasses to nest in. Undergrazing on the other hand, can leave the grasses too long and dense for either of these seasonal needs. We're fortunate that due to the considerable scale of the Dee Estuary saltmarsh, we're able to have a range of grazing intensities, from completely ungrazed, younger saltmarsh at Parkgate to a combination of moderately grazed and more heavily grazed areas of Burton Marsh.
Over the years we've created a mosaic of habitat conditions to favour the different birds' needs in different parts of the saltmarsh, but ultimately deliver as best possible for all of the priority species. Since the saltmarsh is in effect one huge field, in order to achieve this, we introduced some fenced areas to contain sheep to provide a higher grazing pressure where needed; the photo below shows the clear difference in appearance from being grazed on the right side and ungrazed on the left.
The impact of different grazing level on either side of a saltmarsh fence (Colin Wells)
After well over a decade of this management delivered by a tenant farmer, we have seen improved numbers of redshank - more than 200 pairs across the entire saltmarsh - and skylarks successfully nesting, whilst winter pink-footed geese numbers have risen sharply from around 1000 to well over 10,000 now.
In terms of watching birds here, the aforementioned Greenway provides good access to the edge of the saltmarsh, from where a range of birds of prey, egrets, and geese can be seen readily in the winter. However, arguably the most interesting is a springtime walk south from Denhall Road towards Burton Point, where along with the resident stonechats and reed buntings along the inner marsh and skylarks and meadow pipits parachuting further out, the farm fields inland from the path are ideal for passing wheatears, whinchat, redstart and ring ouzel.
Additionally, close to Burton Point is a relatively unique feature of a fen with alder-willow carr and small reedbed that has emerged naturally due to a strong freshwater influence here, and hosts water rail, reed, sedge and grasshopper warblers, whitethroat and some beautiful plants incuding flag iris, marsh orchid and common valerian. With such wide open skies it's also a great spot to catch anything else moving between Burton Mere Wetlands and the estuary, feeding swallows and martins, plus the seasonal spectacle of a migrating osprey.