Silver-spotted Skippers sighted again on Stagbury Down

The weather for this week’s transect was kind to GH, LN and BG – warm sunshine with a refreshing breeze to take the edge off the heat. GH had seen several Brown Hairstreaks on his local butterfly transect and we were therefore on the lookout for them on our circuit too. Sadly, we didn’t see any BH this time around, but we were more than compensated by seeing two rare Silver-spotted Skippers on Stagbury Down, where we saw a single individual last week. We’re very much hoping that these late-season celebrities will, in the future, become established on our patch.

​Butterfly numbers this week were down on those of last week, so although the count of Meadow Browns and Common Blues were very similar, there were reductions in the Chalkhill Blues, Gatekeepers and Small Heaths, and no Purple Hairstreaks or Brown Argus. Even so, the discovery of those Silver-spotted Skippers ensured the transect was far from ordinary.

​Count details:
232 Meadow Brown
  45 Common Blue
  15 Small Heath
  14 Chalkhill Blue
    7 Small White
    6 Gatekeeper
    5 Small Copper
    4 Large White
    2 Holly Blue
    2 Silver-spotted Skipper
    2 Speckled Wood
Count summary:
334 butterflies from 11 species.
​
For more info on these species visit
​​butterfly-conservation.org

Finds of the week

Chalkhill Blue (Polyommatus coridon) – the subtle beauty of the Downs.

• Unlike the sky-blue males, females are brown with delicate orange spots, making them trickier to spot on chalk grassland slopes.
• They rely exclusively on Horseshoe Vetch as their caterpillars’ food plant, making them specialists of chalk and limestone habitats.
• Though locally common in large colonies, their entire flight season lasts just a few short weeks in high summer.

Female Chalkhill Blue, Stagbury - Liz North.

Plump sloes in Hill Wood Field - Graham Kenward.

Survey by Brian Gardner, Graham Harris and Liz North 
​submitted to Butterfly Conservation (UKBMS).
​ ​Report by GK, BG & AI.