Chequered Skipper

A single generation is produced each year; the adult flight period occurs between the third week of May to the end of June (4). Eggs are laid singly on a blade of grass, and hatch after ten days or so (5). The caterpillar creates a tube by spinning the edges of the grass-blade together; it emerges from this shelter in order to feed above it (5). Below the shelter it makes notches in the leaf, which may help to retain nutrients and prevent defensive chemicals from entering the region above the shelter (4). Towards the end of September the caterpillar creates another, larger shelter consisting of a number of leaves, in which it hibernates, emerging the following spring (5). It does not feed at this time, but pupates amongst vegetation (4). The adults emerge towards the end of May (5).

The chequered skipper is a priority species under the UK Biodiversity Action Plan. A Species Action Plan has therefore been produced in order to guide conservation action. Butterfly Conservation has also produced an action plan for this butterfly; both action plans are available on-line (see links below). Trade in this species is illegal under the Wildlife and Countryside Act of 1981. An experimental re-introduction programme was started in 1990, with releases of adults at a restored site in Lincolnshire in 1997-9. Breeding has been recorded, but it is not yet known if these trials will prove successful in the long-term (4). Despite these promising steps, conservation action must be concentrated on the remaining natural populations in Scotland, which are still very vulnerable to changes in woodland management (4).

As the name suggests, this small, fast-flying, chocolate-brown butterfly has a chequered patterning on both the hind- and forewings. Although the sexes are similar in appearance, females are somewhat larger than males (1). The caterpillar grows to 2.3 centimetres in length; before it undergoes hibernation it is green with darker green and white lines, but after emerging it becomes brownish white, with pinkish-brown and white lines (5).

In Scotland, the chequered skipper breeds in open grassland. It prefers the edges of woodlands, and most breeding sites tend to occur at the bottom of slopes and at the edges of rivers and lochs (4). In England it inhabited rides and clearings in woodlands, as well as fens and scrubby grasslands (4). It requires the presence of the foodplants of the caterpillar; in Scotland the main foodplant is purple moorgrass (Molinia caerulea), but in England false brome (Brachypodium sylvaticum) seemed to have been preferred (4).

In Britain, this butterfly is currently found only in a small part of western Scotland. It was formerly common in England in the East Midlands, with a few records from as far south as Dartmoor. It became extinct in England in 1976 following a prolonged decline that began in the early part of the twentieth century, but accelerated after the 1950s. Elsewhere the species is widely distributed through Europe and Asia, reaching Japan. It also occurs in North America reaching north to Alaska. It is currently in decline in many parts of Europe and is threatened in Japan (4).

Extinct in England (4). A UK Biodiversity Action Plan Priority Species, and protected under Schedule 5 of the Wildlife and Countryside Act, 1981, with respect to sale only (2). Classified as Vulnerable in Europe (3).

The extinction of this butterfly in England is believed to have been the result of changes in woodland management, in particular the decline of coppicing (4). In addition, some sites were cleared in order to plant conifers (4). At present, unsuitable grazing levels (2), browsing by deer (4) and loss of open areas in woodlands are remaining threats (2).