New London wetland is example of best practice in creative conservation
The new Wildfowl and Wetland Trust (WWT) reserve at Barn Elms in south west London, created from four disused Thames Water reservoirs, is an example of best practice in creative conservation, says the creative conservation charity, Landlife.
The second of three conferences celebrating Landlife’s 25 years of work in the environment, ‘Taking the Plunge’, examined the strategies and problems associated with wetland creation, looking at the example of The Wetland Centre at Barn Elms.
The Victorian reservoirs, used by Thames Water until the late 1980’s, were made up of four concrete edged water basins on 52 hectares of Metropolitan Open Land. The £11 million project was funded by Thames Water, a housing developer, Berkelay Homes, and a range of other sponsors, and is now a diverse complex of wetland habitats, together with an environmental education centre designed for up to 300,000 visitors a year.
The reservoirs were originally designated a Site of Special Scientific Importance (SSSI) in 1974, with nationally important numbers of Tufted Duck and Pochard, and regionally important numbers of Gadwall, Teal and Shoveler. By the end of the 80’s the importance of the site had declined dramatically due to activities on the reservoir.
November 1995, however, saw the beginning of construction work to convert the site into a reserve. Now divided into six distinct habitat units, water levels in the reservoirs can be controlled to prevent or encourage seasonal variations. There has also been extensive planting, including 10 hectares of native grassland, and up to 30,000 trees/shrubs, and 270,000 aquatic plants.
The wetland has two main objectives, says WWT. Firstly, over 30 hectares were designed to maximise the feeding, breeding and roosting opportunities for a wide variety of wetland wildlife, particularly for those species for whom the reserve was first designated a SSSI. The reserve also supports habitats that are rare or declining in Greater London, such as reedbeds and grazing marsh, as well as species in a similar predicament, such as Redshank, Snipe, and Little-ringed Plover. Habitats at the reserve range from open water lakes, reedbed and wet woodland, through to seasonally inundated grassland and mudflats.
The second objective is in enabling visitors to watch wildlife at close quarters without compromising the conservation value of the site and, through state of the art exhibits, to learn more about wetland values and threats.
“I think Sir Peter Scott’s vision of the Barn Elms site has very much come to reality,” said Richard Bullock, WWT Senior Ecologist.
Problems that the WWT encountered during the five years it took to develop the site included the introduction of undesirable plant species such as floating pennywort, either through the water source, or due to bad labelling at plant nurseries. The possibility of the future accidental reintroduction of large fish, has not been ruled out, explained Bullock, though they have the facility to drain the water bodies and de-fish.
“The important thing is we have learnt many lessons along the way,” said Alastair Driver, the Environment Agency’s Regional Conservation Manager. “We’re still learning.”
The conference also heard from the Welsh Wildlife Centre, in Cardigan, where water buffalo have been used successfully to graze the coarse wetland reeds and shrubs. The vegetation is also broken down by their horns, and wetland pools opened up through the buffalo’s love of wallows. The water buffalo are a docile species, and are used to produce lean meat and mozarella cheese, explained Chris Lawrence, Conservation Officer at the Welsh Wildlife Centre.
The conference concluded that there are a number of problems associated with wetland creation:
- a lack of information available as to the requirements of individual wetland species, particularly with reference to water and aeration stress;
- a lack of knowledge about the volumes of water required to keep a wetland wet;
- a need to look at water quality;
- a lack of knowledge as to the cost of a wetland construction project;
- a need to examine whether water for the wetland be robbed from another user, such as other wetlands, farmers, or water companies;
- the availability of water throughout the year.
Landlife practices ‘creative conservation’, putting wildlife back where there has previously been none, a spokesman from the charity explained to edie. Current projects include turning areas of derelict land in the North West into wildflower meadows, where local people can hold community and arts events, and begin to appreciate wild flowers.
The first conference in the set of three studied climate change, and took place at the Maritime Museum in Liverpool, where the earliest measurements of sea change took place.
The third conference, held on conjunction with Plantlife, takes place in February 2001, and will focus on sowing wildflowers, and seed provenancing. One issue to be examined will be whether or not it is desirable to take wildflower seed from one area of the country to plant in another.