Autumn 2010
2010 Butterfly Conservation Report Rob Parker gives an overview of the butterfly season, presented as a slide show at the AGM The colony we translocated to Blaxhall Common in 2007 also had its best-ever year, with a peak of 31 butterflies counted during the 6-week period they were flying on the transect. At the other end of the scale, visits to Purdis Heath never found more than 3, re-affirming the importance of extending our efforts to improve the deteriorating habitat before the colony is completely extinguished. Neil Ravenscroft’s survey highlighted the decline of the flight area over 20 years, and we now plan a conservation project for the benefit of all the Ipswich heaths.
The year began with a relatively harsh winter, with persistent heavy frosts and strong winds which killed tender plants and will have had a significant impact on overwintering eggs, larvae & pupae. Nonetheless, spring butterflies appeared in reasonable numbers, and the first impression was that all was okay. In the longer term, the year has been something of a Curate’s Egg – good in parts, but very flat otherwise. Most of our common butterflies had a mediocre season, yet some of our BAP species had a really good year. Dingy Skipper Survey. Once again, none was found at Center Parcs or at RAF Barnham. On the other hand, there were 2 causes for optimism. The flight area in the east side of King’s Forest seems to have extended, and work to improve the habitat there continues. Unexpectedly, Sharon Hearle came across 4 Dingy Skippers flying in a young plantation in the south part of the Thetford Forest. This lies just north of the old Marmansgrave Wood site, and is only a mile from RAF Barnham.
White-letter Hairstreak. The hot drought days of July proved to be perfect for inducing White-letter Hairstreaks down from the elm canopy to find nectar at bramble and thistle. Six recorders managed to photograph them in gardens and at spots not known as established colonies, and a dedicated search re-discovered them at the SWT reserve in Bloodhill Quarry. White Admiral. This was a pleasingly strong year, with good numbers at many of the known sites and no less than 12 reports of White Admirals dispersing to places not usually considered to be host colonies. One almost black specimen of ab. obliterae was photographed by Jon King on the Hadleigh railway line walk, and another by Mervyn Crawford in Mildenhall woods.
Silver-studded Blue. The annual survey counted over 7000 S-sBs – with good results at the larger sites. Especially pleasing were an expanding colony in Minsmere’s reversion field, and at the southern edge of the Dunwich Forest, where the Westleton Heath colony has quickly re-colonised a forest compartment felled by the RSPB specifically to allow heathland regeneration.
Silver-washed Fritillary. Undoubtedly the
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