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Dragonflies in Leicestershire and Rutland, 2006
I would like to begin this review of 2006 with my annual thanks to Richard Fray for his continued mastery of the Leicestershire and Rutland Dragonfly Group website (www.lrdg.org.uk) from his remote location in Tucson, Arizona. Although formal record submission was again disappointingly low, 2006 can only be described as the most exciting year in VC55 since the LRDG was formed. In spite of receiving significantly less observer interest than the events of the late summer, the discovery of a new colony of Variable Damselflies at Priory Water in May was probably the most important event from a conservation perspective. This is only the second site in VC55 where this species is known to exist, with then other being the Grantham Canal. Now that the Grantham Canal has such an uncertain future, in light of British Waterway’s proposed developments highlighted in last year’s summary, it is reassuring to know that this species occurs at another locality. Intensive surveys into the distribution of White-legged Damselfly in VC55 continued in the early summer. This species was recorded for the first time on the River Welland upstream of Market Harborough, thought was found to be absent from the Welland in the vicinity of Market Harborough itself and for several kilometres downstream, no doubt as a result of water quality issues arising from urban runoff. It was again found to be present on the River Welland immediately east of the village of Welham and from here all the way to the Leicestershire border. Another interesting discovery was the presence of this species on the Eye Brook, both above and below Eyebrook Reservoir, and also on the headwater of the River Chater in Rutland; further survey work is needed to establish the full range of White-legged damselfly in this County. The most intriguing White-legged Damselfly records came for the Ashby Canal, in the far west of Leicestershire. Prior to 2006 there had only been three records from this linear site, which has received much recording coverage over a number of years. In the summer of 2006, however, this species exploded in both numbers and range being found from the southern border with Warwickshire right up to Shackerstone, some 23 kilometres to the north. Whether this expansion is related to climate change, improvements in water quality, or some other factor is not known, but it certainly represents one of the most abrupt changes of distribution ever documented in VC55. The map below shows the distribution of White-legged Damselfly in VC55 to the end of the 2006 recording season. The unfilled circles show pre-2000 records and the solid circles post-2000 records. For most observers the highlight of 2006 was undoubtedly the long-awaited appearance of the Small Red-eyed Dragonfly in VC55. The inaugural records came from Priory Water, close to Asfordby, on the 22nd July, where numbers rapidly built up to a phenomenal maximum of 180 males, 70 females and 63 ovipositing pairs on 5th August. Late July to early September brought records from a further six sites in central and north east Leicestershire (namely Newton Harcourt, Little Stretton, Thurnby, Stoughton, Kirby Bellars and Frisby on the Wreake) and a single site in Rutland, close to Egleton. The total number of Small Red-eyed Damselflies reported in VC55 in 2006 was around 550 to 600 individuals and it is notable that copulating pairs were noted at all of the above sites and ovipositing observed at most; this species has certainly arrived in force! The distribution of the sites from which the records came paints an interesting picture. All records were to the east of Leicester City. One centre of records was immediately east of the City conurbation itself, roughly in a belt between the A50 and A447. The other centre was in the Wreake Valley just south west of Melton Mowbray, with the remaining outlier close to Oakham. This distribution is made more intriguing by virtue of the fact that further 2006 records came from south east Derbyshire and south west Nottinghamshire. Has Small Red-eyed Damselfly really leapfrogged the whole of western Leicestershire to reach these sites or has it arrived and remained undetected, in spite of concerted efforts to prove its presence here? Such leapfrogging, characteristically carried out biannually, does seem to be a trait of the expansion of this species. In 2004 it was recorded to within approximately 10km of the Leicestershire border in both Northamptonshire and Warwickshire. In 2005 it chose to move no further, yet in 2006 it suddenly pushed up into Leicestershire, Derbyshire, Nottinghamshire and Lincolnshire. It will be interesting to see what developments 2007 and 2008 bring to this fascinating real-time study of odonata colonisation. Finally, when it seemed that no more excitement could possibly befall VC55, the first of up to 12 fresh teneral Red-veined Darters appeared at Huncote. The initial observation was made on 3rd September and the last on 7th October, with local emergence being strongly suspected from the first instance. Although no larval or exuvial proof was obtained, it as assumed almost beyond doubt that the insects emerged from a nearby private sand quarry; such a record would represent the first breeding of a species for which there had previously been just two VC55 records. Additionally a further four male Red-veined Darters were observed at Priory Water between mid June and early August, though there was no reason to suspect breeding at this site. Finally, a recently received record of a Common Darter at Rutland Water on 26th November was the latest ever by 10 days, though even this may be beaten as the mild weather continues as I write. As can be seen, 2006 may take some beating in terms of excitement from an odonata perspective; or will it? One can only assume that global warming is the underlying cause driving many of these exceptional events and it may be that such dramatic occurrences become the norm due to the changing climate with which we must now all live. Ian Merrill, December 2006
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