Monday, 12 August 2013

Precious metals ...

Surrey Downland, 30-31 July 2013

The Silver-spotted Skipper (Hesperia comma) is a warmth-loving species. Its range contracted during the 20th century due to a reduction in grazing stock as well as the onset of myxomatosis in the early 1950s, which severely affected rabbit populations; the butterfly requiring closely-grazed chalk downland sites on which its primary larval foodplant, Sheep's-fescue (Festuca ovina), grows. Recent years have been more promising and this is one of the few species that is increasing its range. It is still relatively-local, with current strongholds being located in the Chilterns, Hampshire, the North Downs between Guildford and Reigate, East Sussex and south-east Kent. It occurs locally in my own county of West Sussex and is currently showing a positive trend for expansion into adjacent suitable habitat.

It is easily identifiable, since it is the only golden skipper found in the British Isles that has the distinctive white spots on the underside of the hindwings, which give the butterfly its name. Like other ‘golden’ skippers, the male is distinguished from the female by the sex brand on its forewings, which is a line of specialised scent scales.

H. comma is one of the latest species to emerge, typically not appearing until late July or early August, and it is then on the wing until early September. There is one generation each year. Like most skippers, this is a fast-flying species that flies close to the ground, and can be extremely difficult to follow when in flight. Both sexes spend the majority of their time either basking or feeding, and a wide variety of nectar sources is used. The butterfly will find the warmest patches of ground on which to bask, enjoying the warmth of paths, rabbit scrapes and other patches of bare earth, which have been baked by the sun. The males rest on suitable sunlit perches, and will investigate any passing butterfly, in the hope of finding a mate. If a virgin female is encountered, the pair exhibits a tumbling courtship, with the male eventually forcing the female to the ground where mating takes place. An egg-laying female locates a suitable patch of bare ground, such as a rabbit scrape, and then walks to the edge of the patch looking for a suitable location on which to lay a single egg.

A female at rest pictured below ...

No comments:

Post a Comment