Pearl-bordered Fritillary Sites in Scotland requiring surveying in 2009
The Pearl-bordered Fritillary is a high priority species. It is a UKBAP Priority Species and is included on the Scottish Biodiversity List. It has recently been designated a Species Action Framework Species by SNH. Although still relatively widespread in the UK, most colonies are small and vulnerable to changing management It has declined rapidly across the UK, particularly in England, and Scotland is now the major stronghold but we believe it is still under-recorded with many sites having few recent records, hence the need for this survey.
Owing to the efforts of Butterfly Conservation staff and volunteers over the last 20 years, approximately 270 Pearl-bordered Fritillary sites have been identified in Scotland with the caveat that some could be the very similar Small Pearl-bordered Fritillary.
However, many of these sites have not been visited in the last five years according to Butterfly Conservation Scotland's records, and some have not been visited for several decades. Therefore, these web pages which list the sites which have not been visited in the last five years (some sites have been included where a visit has been made in the last five years but Pearl-bordered Fritillary was not found) have been constructed to help direct volunteer effort to visit these sites in May 2009.
When to Do
The best time to survey adult Pearl-bordered Fritillary is during the first three weeks of May when ONLY Pearl-bordered Fritillary are on the wing and before Small Pearl-bordered Fritillary appear. Any individuals seen between 21 May and early June may be either Pearl-bordered or Small Pearl-bordered, hence earlier survey dates are preferred but visits in this period may be undertaken if poor weather or circumstances prevent an earlier visit. However, the flight phenology at the higher altitude sites in eastern & highland Scotland is significantly later extending until late June or even early July.
Both species are easy to spot as they are bright orange and active on warm and sunny days. For information on how to identify Pearl-bordered & Small Pearl-bordered, see information below the Scotland map and download the Butterfly Conservation leaflet on Pearl Bordered Fritillary here. For more information, contact Tom Prescott:
To find more information on sites in your branch area, please click on the relevant branch area in the map below:
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Highland Scotland Branch
- 69 sites in West Highlands
- 35 sites in East Highlands
Eastern Scotland Branch
- 18 sites in South Aberdeenshire
- 26 sites in Perthshire
Glasgow & SW Scotland Branch
- 16 sites in Dumfries & Galloway
- 1 site in South Ayrshire
- 12 potential sites in Loch Lomond & Trossachs National Park
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Description
Similar in appearance to Small Pearl-bordered Fritillary (Boloria selene) but Pearl-bordered Fritillary has an earlier flight period commencing late April to early June while the Small Pearl-bordered flies from late May onwards. Both are medium-sized bright orange butterflies with similar markings on the upper wings except for the black chevrons on the upper forewing being more separated from the dark border in Pearl-bordered but joined to the dark border in the case of Small Pearl-bordered. The different markings on the under hind-wings are the best method of distinguishing between these two species. The Pearl-bordered Fritillary has a small dark spot near the base of the hind underwing with two silver/pearl white cells on either side and a generally tawny appearance and the white outer cells are bordered by brown chevrons.
The Small Pearl-bordered Fritillary has a larger black spot near the base of the hindwing surrounded by seven silver/pearl white cells which are bordered by black as are the white cells on the margins of the hindwing. Caution is required though as Small Pearl-bordered Fritillaries are very variable and worn individuals can look very similar to the much rarer Pearl-bordered Fritillary.
CAUTION: These photos represent contrasting examples of these two similar Fritillary species but the markings of some individuals, particularly worn ones, do not make identification easy. Make identifications on the basis of underwings rather than upperwings.
More photos can be seen on UK Butterflies: Pearl-bordered Fritillary; Small Pearl-bordered Fritillary.
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