The descriptive text, below the map, is from the Cornish Red Data Book (2009). The map on this web page depicts the organisms distribution and shows the records made pre-2000 and those made since.
Range & Status
Rare and has a local distribution in England and Wales. Its population has declined by 64% since 1977 although it has increased by 10% over the ten years to 2004 (Fox et al. , 2006). Widespread in Europe and to Siberia with some decline (Asher et al. , 2001).
Most records are from two distinct areas: Millook to Marsland in the north of Cornwall and to the north and east of St. Austell. May be extinct in Cornwall as only one record has been received since 1991 at Pontsmill in 2004.
Habitat & Ecology
A butterfly of ' edge' habitats, at Millook, Frohawk (1924) found it commonly flying in lanes along hedges. Egg laying takes place in lightly shaded, sheltered areas, individually on the underside of food plant leaves which protrude above the surrounding vegetation. The larva feed individually usually at the top of the plant on the younger growth. Disperses away from the foodpland to pupate in shaded areas 20-40 cm above the ground (Asher et al. , 2001). Overwinters as a pupa.
Lack of grazing leading to excessive shade of foodplants.
None known. Grazing regimes in north Cornwall coastal valleys for the re-introduction of the Large Blue may be beneficial. A UK BAP priority species.
I.J. Bennallick, S. Board, C.N. French, P.A. Gainey, C. Neil, R. Parslow, A. Spalding and P.E. Tompsett. eds. 2009. Red Data Book for Cornwall and the Isles of Scilly. 2nd Edition.Croceago Press.
The Cornish Red Data Book Project was led by the Cornwall and Isles of Scilly Federation for Biological Recorders (CISFBR). The full text and species accounts (minus the maps) are available on the CISFBR website.