Discovery of a colony of rare dragonflies was one of the highlights of this year’s survey of The River Stour (Kent) Internal Drainage Board’s watercourses.
Carol J Donaldson Associates undertook a survey of twenty IDB channels this year on behalf of the Kentish Stour Countryside Partnership and the IDB, ranging from fast flowing streams winding their way through banks of marsh marigolds to slow moving drainage channels with a diverse array of waterweeds. “Surveying the entire length of each channel reveals both the opportunities and the threats,” said Carol Donaldson. “This year we found small amounts of the invasive species, Japanese knotweed, growing close to one channel and a badly installed culvert which had caused erosion and created a weir, which was impeding fish passage upstream. Identifying and dealing with these issues at an early stage can save landowners costly remedial action down the line.”
We also spotted opportunities to enhance wet woodland habitat, prevent flooding downstream and undertake management work to create pinch points in channels, where possible, which would restore gravel beds, important for spawning trout.
“The network of River Stour IDB channels covers the full length of the Stour catchment.” said Carol. “Positive management can make a real difference for farmland wildlife such as reed buntings, a National Biodiversity Action Plan target species which have seen a 67% decline in the last 30 years and barn owls, which rely on uncut ditch edges to hunt for voles.”
This year Carol J Donaldson was assisted by Sue Buckingham, County Plant Recorder, who conducted plant surveys on some of the most valuable channels and Will Hirstle who undertook odonata surveys which revealed the colony of scarce chaser at the RSPB Lydden Valley Reserve, a first recording for the reserve since the RSPB took over management.
“Discovering a new colony of scarce chaser dragonfly shows that in many cases the IDB are getting the management right.” said Carol. “Often it is about balance, too much or too little management and the habitat could be compromised, but it is also about balancing the needs of wildlife with drainage and flood management. Our job is to provide the IDB with the information it needs to make the right decisions to get this balance right.”
Read Will’s article on scarce chasers here;