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| Fenland Ditch, Wood Walton Fen
© Roger Key |
Why are ditches so special?
Ditches snake through grazing marsh land in many parts of the British countryside, creating a network of freshwater life. Although a man-made habitat ditches support a wealth of invertebrate and plant life. Numerous wetland and water plants adorn their margins providing a refuge for a glittering array of rare water beetles including the BAP species: One-grooved diving beetle (Bidessus unistriatius).
Rare water invertebrates
Other BAP species found within this habitat include threatened invertebrates, such as: Fen raft spider (Dolomedes plantarius), Lesser water-measurer (Hydrometra gacilenta) and Shining ram’s-horn snail (Segmentina nitida) as well as BAP plant species, the Bird’s nest stonewort (Tolypella nidifica). Ditches also provide a habitat for numerous nationaly rare species.
Threats to Ditches
Ditches are yet another of the UK’s threatened habitats. They are rapidly deteriorating in quality due to range of issues, including: agricultural pollution, unsuitable water level management and ‘managed retreat’ schemes. One of
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| Fen Raft Spider © Roger Key |
the biggest problems is wholesale clearance of ditches, which is still common practice in many agricultural areas. However, to date there has been little research and therefore a lack of understanding in regard to the affect of these issues on ditches and the rare species they harbour.
Buglife's Ditch Project
Buglife undertook a large three-year survey of ditch systems 2007 to 2009; re- surveying ditch faunas in nationally important grazing marsh sites, to assess recent change and identify management techniques to preserve aquatic and semi-aquatic invertebrates. This project was funded by the Esmée Fairbairn Foundation, the Environment Agency, Anglian Water, Peterborough & Norwich Building Society, the Broads Authority, Courtyard Trust, the Norfolk Biodiversity Partnership, Natural England and Countryside Council for Wales.
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| Braunton Marsh © Roger Key |
How will this project make a difference?
This project has produced a series of management advice sheets for land managers and professional to help them support this rich and threatened habitat. These are:
Project Reports
The final technical report for this project is now complete, this report contains details on the classifications, evaluation and changes over time for invertebrate and botanical assemblages. It also contains information on species of conservation concern, details on individual marshes and the effects of environmental attributes. For a copy of the technical report please click here. For more information on the data analysis used in the report see Volume 2 of the report.
To accompany this project Rob Driscoll completed a comprehensive bibliography of previous surveys entitled'Ditch Surveys Part 1: Surveys 1878 to 1999'. This and further technical reports are detailed in the ‘Project time-line’ table below with links on the right-hand side.
Project time-line and achievements
| Year | Activity | Reports |
| 2007 | Rob Driscoll completed a comprehensive bibliography of previous surveys.This bibliography lists all ditch surveys undertaken in a 121 year period (between 1878 and 1999)! | Ditch Bibliography 2007 Click here |
| The project has produced a Ditch Manual detailing standard methods for surveying the vegetation and aquatic macro-invertebrates of ditches. The manual describes a method for evaluating ditches utilising plant and macro-invertebrate data. | Ditch Manual Version 4 Click here |
| 2007 saw the plant and invertebrate surveys completed on the Gwent and Somerset Levels, by our tireless surveyors Martin Drake and Nick Stewart | Project Report 2007 Click here |
| 2008 | The Marshes: North Kent, Pevensey and Walland, Maltreath and Amberley were the focus of surveys in 2008. Highlights of the survey work that was completed, include: the Medicinal leech (Hirudo medicinalis) at Walland Marsh and the Fen raft spider (Dolmedes plantarius) at Pevensey Marsh. | Project Report 2008 Click here |
| Survey work is also examining the diatom species present in ditches. Diatoms are single celled microscopic algae, which can be found in both marine and freshwater habitats. They cover the surfaces of aquatic plants where they link together to form colonies. In this project they are being used to assess water quality, as many species can be used as indicators of environmental conditions. Survey data will also be used to extend knowledge of diatom communities in ditches and their relationship with plants and invertebrates. | Diatom Report 2008 Click here |
| 2009 | Norfolk, Suffok and North Essex were the surveyed in the 2009. The survey work found a number of records for the European important species Little whirlpool ram's-horn snail (Anisus vorticulus) and the rare and beautiful Norfolk Hawker (Aeshna isosceles). | Project Report 2009/10 Click here |
| The project has also looked at a time series dataset covering 1973, 1981, 1982, 1997 and 2009 for ditches in the Upper Thurne catchment, Norfolk. This combined dataset was analysed for trends in invertebrate and plant species. Distinct trends were seen in relation to land use and management on arable and pasture farms. Arable ditches were found to be of lower ecological quality compared with ditches in pasture and arable ditches were seen to take a long time to recover after land use was converted to pasture. | Upper Thurne Catchment grazing marsh ditches 1973 to 2009 – Final Report Click here |
To see the Ditches project summary sheet click here.
For information on Buglife’s other freshwater projects click here or click on the links in the left hand panel.
