The Suffolk Argus
Summer2006
Species Maps
Bemer's Heath [TL7977J. The northern edge of Berner's Heath has plenty of Bird's-foot Trefoil along the rather exposed northern edge. It was visited twice (May 16th in poor weather & Jun 17th in good conditions) without success.
Annual Report on Silver-
Distribution Maps for individual species have been prepared for our 31 regulars, and these are available for reference as required. This year's total species count stands at 33 if the introduced Purple Emperor is included.
Analysis Relative scarcity can be deduced from a count of the number of tetrads from which each species has been recorded. Our rarest native butterflies are usually the 3 BAP species, followed by the White Admiral. This year's league table reflects a numb~r of changes, with Clouded Yellow appearing high up as a result of the poor migration season. Encouragingly, White Admiral and Holly Blue are much improved, but worryingly, the Wall was only found in 6% of the squares surveyed. Year-on-year change is not simple to quantify: a straight tetrad count is less meaningful than the percentage of survey squares in which each species was found. Neither measure assesses a butterfly's abundance at its breeding sire as accurately as the "index" derived from transect walks.
studded Blue for 2005 by Rob Parker Season 2005 started late by comparison with the past 2 s.easons. A cool, wet spring protracted larval feeding, and the butterfly was not on the wing until June 18th, compared with June 7th in 2003/4. A summer interrupted by heavy rain spoiled survey effort as well as depressing the peak figures at most colonies. Relatively low temperatures reduced the prospects for colonising activity late in the summer.
Transects Derailed data was submitted for the established transects at North Warren (Rob Macklin), Fynn Valley (Richard Stewart), RSPB Minsmere (Robin Harvey), Bradfield Woods (Steve Hunt), Center Pares (Graham Hersey-Green), Cavenham Heath (Michael Taylor), Walberswick (Adam Burrows) and Bury Sr Edmunds (Rob Parker). Four new transects have also produced results this season: Wolves Wood (Mark Nowers), Newsons Farm (Frances Bee), Barham picnic site (Nick Dickson) and Upper Abbey Farm (Trudy Seagon), bringing the roral to 12 full transects and 3 single-species transects. Special thanks are due to all those transect walkers for their regular monitoring, which provides an objective abundance count as well as site-specific observations, and flight times.
The Counts The main count at Minsmere had been planned for June 20th, and a team of volunteers counted the two main colony areas until it became clear that the population was predominantly male, and well short of its peak. Unfortunately the re-count two weeks later was hit by torrential rain, and the third attempt was past the peak, so the results were unsatisfactory. Most other colonies were adequately counted, although recorders had to make several visits to get reasonable results. An initiative to inuoduce mini transects at Minsmere got off to a poor start, but was trialled sufficiently to devise a workable plan for future years.
Annexes [to be published later]: Scarcity 2004 & 2005 Analysis of 11 Years to 2005 Derailed reports for BAP species. Silver-studded Blue Dingy Skipper and White-letter Hairstreak
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Sketchfar [TL836801J. See remarks above, under Marmansgrave Wood. Shepherd's Grove [TL987l}. This area has some Bird's-foot Trefoil on the former airfield, not far from the planned IKEA development. It was surveyed on Jun 8th, but did not appear suitable for Dingy Skipper.
DingySkipper by DouglasHammersley
Haverhill Industrial [TL6844). This area (mainly just outside VC26) has Bird'sfoot Trefoil, and had been suggested as a postindustrial site worth inspection. Three visits were made, but no Dingy Skipper were found.
Euston Quarry [TL896775}. This wonderful CWS has everything that ought to make a good Dingy Skipper site, including Bird'sfoot Trefoil and a Common Blue colony. It was inspected early this year, on May 8th, but for the third year in succession, no Dingy Skippers were found.
Rob Parker,County Butterfly Recorder. July, 2005
OTHER SITES (Inspected, with negative results)
LANDOWNERS (and other interested parties, for reference)
Cut-off Channel [TL7386]. , During Norfolk's 2004 survey for Grizzled ancf Dingy Skipper, both were found along the watercourse known as the Cut-off Channel, which has a chalky double embankment along a nine mile stretch in Norfolk. Visits to the Suffolk stretch were made on May 12th (after finding DS flying \n nearby Norfolk), but there was a shortage of Bird's-foot Trefoil, and nothing was seen.
Euston Estate (Chris Spicer) Elveden Estate Qim Rudderham) Thetford IP24 3TQ Stamper Farms O.Stamper, West Farm) IP24 North Farm (Rob Watson) IP24 East Farm (David Heading) Barnham IP24 2QN Forest Enterprise (Nick Gibbons) RAF Hanington (Gwyn Smith) Center Pares (Ecology Manager) Brecks Countryside Project Norfolk Butterfly Recorder (Patrick Bonham) BC EoE Regional Officer, Butterfly Conservation (Sharon Heade) East of England Tank Museum (Sean Hindle) Barnham IP24 Environment Agency Suffolk Biodiversity Partnership
Thetford Rifle Range [TL8480J. This MoD site lies in administrative Norfolk, bur is in Suffolk's biological recording area. It has plenty of Bird's-foot Trefoil in a suitably sheltered area, and was walked extensively on May 24th in poor weather and again on May 25th in hot weather. Although the habirat looked excellent, it was disappointing not to find any Dingy Skippers.
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