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Dragonflies in Leicestershire and Rutland, 2005
Dragonfly recording doesn’t commence with the Spring emergence of the first large Red Damselfly and again Helen Ikin and I were busily manipulating data through the winter months. A long and laborious task was to check through hundreds of site descriptions and grid references in an attempt to eliminate duplication as far as possible. Another useful output was the production of species value and species richness indexes for all of the main Leicestershire sites; it was no surprise to discover that the fantastic Grantham Canal came top of the league. I have previously reported that British Waterways plan to make this canal navigable once more and that the fantastic aquatic wildlife at this site looks set to suffer as a result. Planned mitigation measures appear woefully inadequate and I would again urge anyone with concerns about the proposed project to address them direct to British Waterways. Early in 2005 Richard Fray undertook a major overhaul of the Leicestershire and Rutland Dragonfly Group website, which included the commencement of the uploading of species distribution maps. Regular updates of VC 55 (Leicestershire and Rutland) sightings were added throughout the flight season, as were some magnificent images of the odonata observed. Record submission was rather lower for 2005 than in recent years and produced little in the way of surprises. It was noticeable that Hairy Dragonfly was less in evidence than in 2004, though the Grantham Canal was again the best site at which to search for this relatively recent coloniser. It is also worth noting that, in spite of much searching, Small Red-eyed Damselfly again failed to make the short crossing from established strongholds in Warwickshire and Northamptonshire and onto the VC 55 list. The most significant advance in our knowledge of the distribution of the region’s odonata came from the results of intensive survey work on the White-legged Damselfly in Leicestershire, which are illustrated on the ‘Mapmate’ generated distribution map below. Note that solid dots represent records from 2000 to 2005 and unshaded dots represent pre-2000 records. Commencing in the southernmost reaches of the County, it can be seen that the species is now proven to be present along the whole stretch of the River Avon between the Warwickshire border and Stamford Reservoir. Systematic surveying of the Grand Union Canal has revealed that White-legged Damselfly is present from the point where the Canal meets the Northamptonshire boundary northwards to the town of Wigston, which is effectively the southern boundary of the Leicester City conurbation. Its disappearance from the Canal at this point is presumed to be as a consequence of deteriorating water quality within the urban environment. The most revealing results came from surveys of the River Wreake and its tributaries, to the north east of Leicester, which held the most significant populations of any areas visited to date. At the southern limit of the catchment the species was found in the River Wreake where it joins the River Soar, just east of Rothley, but was not present in the Soar itself. Again, this observation was assumed to be a function of water quality. White-legged Damselfly was found in every 1 km Ordnance Survey Grid Square on the River Wreake between the River Soar and Melton Mowbray. It was noted for the first time on the Queniborough Brook, where it was present from its confluence with the Gaddesby Brook to a point just east of Queniborough village. A population on the Gaddesby Brook was traced from the confluence with the River Wreake as far west as the village of Twyford. To the east of the town of Melton Mowbray the River Wreake becomes the meandering and well-vegetated River Eye, which was found to contain the largest populations of White-legged Damselfly in the catchment. The section of the River in the vicinity of Brentingby and Wyfordby produced the most prolific counts, with numbers gradually reducing eastwards to Stapleford. In 2006 it is hoped that the complete picture of White-legged Damselfly distribution in VC 55 can be painted, with an extensive survey of the River Welland and its tributaries in the south eastern boundary of the Vice County. Ian Merrill, December 2005
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