Records suggested that the Chequered Skipper butterfly is restricted to within a 30 mile radius of Fort William. However, computer modelling suggested that the distribution of the butterfly may be underestimated by around 20% at a 10km square resolution. We therefore encouraged volunteers to survey the top 100 1km squares predicted by the modelling to be suitable for the butterfly where it has not previously been seen.
Over the three years of the survey (2012-4), 57 of the top 100 1km squares were visited. Chequered Skippers were recorded in just over half of them, 32 (56%), but not in 25. 43 squares remained unsurveyed.
However, butterfly was also recorded in 72 other 1km squares where it had never previously been recorded, thus giving a total of 104 new 1km squares! This has increased the known range of the butterfly at a 1km resolution by almost 42%.
The majority of new 1km squares are infilling within the butterfly’s known range, but there are a few minor range extensions particularly at the south of the range and the far northwest, but the most obvious extension is westwards along the Ardnamurchan peninsula. Here the Chequered Skipper was recorded for the first time to the west of Salen, in three new 1km squares near Glenborrodale and with a single sighting much further to the west, near Sonachan.
To all the volunteers who went boldly where no recorder had been before! It was well worth it!
For more information on the butterfly see our Chequered Skipper leaflet which you can download.