I received the following report from Michael Walter a few weeks ago - despite this posting being delayed, what he says is still relevant:
‘After a disappointing spring for birds, and a late season for the heath fritillary, it has been heartening to see so many of the common and some rarer summer butterflies around this year. Gatekeepers enjoyed quite a good summer, and in early September there was a glorious profusion of peacocks and the three common species of whites. I have even seen several small tortoiseshells, now just about our rarest butterfly, and it is quite possible that these, along with the whites and occasional clouded yellow that have turned up at Blean are all of continental origin, like the long-tailed blues that were found feeding on everlasting pea along the clifftops near St Margaret’s.
Another encouraging sign this year has been an increasing number of sightings of brimstones, which nearly became extinct on the reserve in 1999, for reasons unknown, and have been extremely scarce ever since. The common blue, a real jewel of an insect when viewed in strong sunlight, has had its best year since monitoring began at Blean in 1982.
By early September, the numbers were naturally well into decline, with all the peacocks and most of the whites having disappeared, but a visit still produced four brimstones, a holly blue, a small copper (another stunner) and, most surprisingly, a slightly tatty silver-washed fritillary, which was far later than usual.
All in all, the butterflies have come up trumps at a time when it seemed as though we were doomed to suffer a dismal summer after the unmitigated gloom of spring'.
More information on the national picture for butterflies this summer can be found on the BTO’s website at: http://www.bto.org/volunteer-surveys/gbw/about/news/latest/2013/butterflies