Information and Advisory Note Number 131 Back to menu
1.1 Although Scotland supports only half of Britain's resident butterfly
species, several Scottish species and populations are particularly important in
the UK context. Within the UK, three species - the chequered skipper, mountain
ringlet and scotch argus -are almost entirely restricted to Scotland, while
several others with important Scottish populations (e.g. pearl-bordered
fritillary, marsh fritillary and large heath), have declined significantly in
England and Wales.
1.2 Of the 28 butterfly species currently resident in Scotland, 16 are considered to be habitat 'generalists', or use habitats that are widespread. The remaining 12 are regarded as habitat specialists, in that they are restricted to scarce or very 'narrow' habitats. Four of the latter are UK Biodiversity Action Plan (BAP) Priority Species (chequered skipper, northern brown argus, pearl-bordered fritillary and marsh fritillary).
2.1 The geographic ranges of the majority of resident Scottish butterfly species
appear to have been relatively stable in recent years. Trends for habitat
specialists and generalists have, however, differed markedly. While 42% of
habitat specialists have shown substantial declines in their range size in
recent decades╣, none of the generalist species
have done so; indeed, 31% of these have expanded their ranges in Scotland
2.2 Factors influencing the two groups are also thought to differ markedly. Declines shown by the specialists have been associated with the continued destruction and deterioration of their habitats, while increases shown by the more widespread species have largely been attributed to climate change. These latter species are able to move through the modern landscape, finding places to breed, even in intensively managed agricultural and urban areas. They therefore have the potential to track shifts in climatic zones as these move north with global warming. Habitat specialists, on the other hand, are becoming increasingly isolated in small patches of semi-natural habitat, and may not be able to keep pace with climate change.
2.3 Butterfly species whose geographic ranges are considered to be expanding in Scotland are the large skipper, orange-tip, peacock, speckled wood and ringlet. Those species considered to be declining, or whose status is unclear, are listed in Table 1.
╣ Adequate trend data are lacking for a further 17% of habitat specialists.
Table 1. Habitat specialists showing range contractions, or for which data are poor
2.4 The speckled wood is a widespread woodland butterfly whose previously extensive Scottish distribution contracted to a small area on the west coast around the end of the nineteenth century. Populations have since expanded eastwards. Over the past two decades one particular population, centred around Inverness, has expanded rapidly through Moray into Aberdeenshire, as well as to the north and west. Recent records from the Mull of Galloway suggest that there may also be small populations in south-west Scotland, perhaps the result of immigration from Northern Ireland.
3.1 This profile has been developed using Asher et a/, (in press), and information kindly provided by Butterfly Conservation.
Asher, J., Warren, M., Fox, R.t Harding, P., Jeffcoate, G. and Jeffcoate, S. (in press). The millennium atlas of butterflies in Britain and Ireland. Oxford: Oxford University Press.
Further detailed information on Natural Heritage Trends: Species Diversity can be found in Information & Advisory Note No. 129.
To obtain further information about any of the issues raised in this l&A Note,
Dr Phil Shaw or Ed Mackey
Environmental Audit Group
Chief Scientist's Unit
Scottish Natural Heritage
2 Anderson Place
EDINBURGH EH6 5NP
Tel: 0131-446 2464
Species mentioned in the text
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