Butterfly Conservation - Upper Thames Branch - Silver-spotted Skipper Report

BUTTERFLY CONSERVATION UPPER THAMES BRANCH

Silver-spotted Skipper Report 2008

Richard Soulsby

Silver-spotted Skippers had a rather better year in 2008 than 2007. The number of reported sites has increased from 9 to 14, with the additional sites mainly being in the northern Chilterns. The numbers of butterflies also held up well, with a report of 112 Silver-spotted Skippers in 90 minutes at Aston Rowant (Beacon Hill). At an Oxfordshire site which is monitored annually with a single-species transect, the peak number was the highest of the last six years.

Despite poor weather from June to August, the flight season was surprisingly early. The first reported sighting of the year was on 24th July and the last was on 14th September.

A special study was made this year of historical records of Silver-spotted Skipper from the northern Chilterns. The earliest recent records were from 1998, with no records between 1984 and 1997, but by 2000 there was evidence of breeding as far North as Bacombe Hill near Wendover. Sightings in this area have been scattered and sporadic. Studies by a reliable source have shown that the golden skippers spend a greater time hidden from view than other butterfly species, so that the true numbers are much greater than those seen. This might help to explain the continued existence of these fragmented sites with such infrequent sightings.