27th July 2015
Despite showers being forecast I was eager to go to Holt Country Park to look for the valezina form of Silver-washed Fritillary. Whilst this species is usually orange, in some colonies a small percentage of the females are instead a bronzey-green colour. Fortunately the colony at Holt, probably the best known one in Norfolk, has this form present. I had failed to see it on previous visits, so I wasn't confident of seeing one, particularly because it was raining as we drove through Edgefield, but by the time we arrived at Holt the rain had stopped and a few butterflies were on the wing.
Last year we saw quite a few Silver-washed Fritillaries on the Buddleia at the back of the car park, and similarly on this visit two were almost immediately visible. Both were vibrating their wings, presumably heating up their flight muscles after a period of inactivity. We took a slightly circuitous route to the pond along a path that had held a valezina a week ago, but didn't see any butterflies at all. Stopping at the pond we scanned the vegetation and saw another normal-type Fritillary. Then bingo, a beautiful bronzey valezina landed on the Hogweed in front of me. I called Cathy round and we both admired the butterfly as it gave excellent views. Further round the same island of vegetation Cathy found a second one, with both showing at the same time to confirm it was a second individual.
Whilst we were here I remembered that one of the wardens was monitoring hoverfly records, so I made an effort to photograph as many species as possible. Of those that are identifiable without examination or a specimen we found eleven, quite good for a small area on an overcast day. These included three Volucella species and two new ones for me, Helophilus trivittatus and Sericomyia silentis. On our way back to the car we saw another couple of orange Silver-washed Fritillaries nectaring on thistles, plus a Red Longhorn Beetle and a Speckled Bush-cricket.
Whilst in North Norfolk we decided to carry on to Sheringham Park. Here I wanted to look for one of my target species for the year, the attractive Rhododendron Leafhopper. We had checked quite a few Rhododendrons without finding any, and then I saw some white leafhopper nymphs. We wondered if it was too early in the season, but Cathy quickly answered that question by finding some adults lower down on the same plant. Rhododendron Leafhoppers are green with red streaks and a black line through the eye, and are well worth a closer look if you see one. The NBN map for this species doesn't show any records for Norfolk, but their presence here is well known, even being mentioned on the Sheringham Park website. We ended a successful trip with chip butties at the park cafe.