Invertebrates

Chequered Skipper (Carterocephalus palaemon) - UK nationally scarce

The chequered skipper is a boreal species that occurs across Europe, Asia and North America, but it is declining in several European countries. The British populations are now restricted to a small area of western Scotland. Chequered skipper populations are small (comprising a few hundred individuals at most) and adults can disperse over large areas. Therefore populations are diffuse and difficult to define. Females lay their eggs singly on tussocks of the larval food plant, purple moor-grass (Molinia caerulea) growing in damp, scrubby areas, often under shade. After hatching, the larvae spend the summer in shelters made from rolled grass blades. They become free-living in autumn and feed until late October or early November when they go into hibernation in the base of purple moor-grass tussocks. The larvae emerge in early April and then pupate for about six weeks before emerging as an adult. Adults are extremely active and require large quantities of nectar and sunshine.

Habitat

In Scotland, the chequered skipper is primarily a species of woodland edge and scrub, particularly oak (Quercus) or birch (Betula). It occurs in areas of non-grazed or lightly grazed grassland, scrub and marsh around open broad-leaved woodland. These areas are occupied by the larval food plant and have abundant nectar plants such as bluebells (Hyacinthoides non-scripta), bugle (Ajuga reptans), marsh thistle (Cirsium palustre), orchids (Dactylorhiza spp.) and ragged robin (Lychnis flos-cuculi).

Threats and conservation

The major threat In Scotland comes from over or under-grazing larval habitats. Deer grazing on many sites prevents the colonisation by trees, thereby preserving the sunny areas and the nectar-producing plants essential to the chequered skipper. An optimum grazing level or rotational cutting should maintain sites at the appropriate successional stage. Rides and wayleaves should be 20-30 m across and free of dense scrub. Schemes involving deer culling, fencing to exclude stock and deer, or bracken spraying are cause for concern because they may lead to a loss of the open areas in woodland on which the chequered skipper depend upon.

For more on the chequered skipper, see the web pages fro :

Source

Douglas, G. 2003. Carterocephalus palaemon Pallas, Chequered Skipper (Lepidoptera: Hesperiidae). Invertebrate species dossier, Scottish Natural Heritage.