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Grizzled Skipper (Pyrgus malvae)
© Nick Greatorex-Davies
The Grizzled Skipper is a very localised and declining butterfly in Britain occuring in discrete colonies in open, sunny but sheltered, unfertilised grassland, woodland rides and glades or abandoned industrial sites, breeding where the vegetation is sparse and there are patches of bare ground. Best sites occur where there is a mosaic of short and long vegetation where the caterpillars feed on rosaceous plants such as Wild Strawberry (Fragaria vesca), Creeping Cinquefoil (Potentilla repens) and bramble (Rubus sp.). (For further details on this species see http://www.butterfly-conservation.org/).
Family: Hesperiidae
Status: Rapid decline
Status details:
Status since 1976 is Rapid decline with a decrease of -35.6%
Status over the last 20 years is Stable with a decrease of -23.7%
Status over the last 10 years is Stable with a decrease of -52%
Back to the topLog collated index plot
This chart shows the index of abundance (LCI = Log Collated Index) over time. It shows fluctuations in populations from year to year, and is scaled so that the average index over the whole series is equal to 2 (horizontal line). For greater detail about how this index is derived, click on the green question mark above.
Trend description:
The Grizzled Skipper has shown an almost cyclic pattern of declines and increases over the monitoring period. There was an unexpectedly high index in 1997, nevertheless the trend shows a significant overall decline. Sites showing the greatest declines have been woodlands where increasing shadiness and the lack of suitable open areas with sparse vegetation is likely to be an important factor. The Grizzled Skipper is not represented on Brownfield sites in the BMS - another important habitat for this species.
Distribution...
This map shows the distribution between 1995 and 1999. Data is derived from the Butterflies for the New Millenium dataset via the NBN Gateway (www.searchnbn.net).
View the distribution on the NBN GatewayPhenology...
Phenology plot
Phenology plot
This chart shows the average number of butterflies seen on transects between Arpil and October. The black line gives average counts over the full BMS series (1976 to date) and the red line gives the average for the last year.
Abundance...
Abundance
This map shows symbols for the mean abundance at transect sites, with the size of symbol reflecting the level of abundance. Means are over all years.
Coverage
In total, Grizzled Skipper has been recorded from 390 transects in the Butterfly Monitoring Scheme. Of these, annual indices of abundance have been calculated from 385 sites, with an average index of 8 individuals per site.
For 188 of these sites, Grizzled Skipper has been recorded well enough to calculate annual indices of abundance in 6 or more years, allowing trends to be calculated.
In 2006, 1146 individuals were recorded from 128 sites, producing annual indices at 91 of these.
This map shows the trend in abundance at particular transect sites. Trends (increasing, declining or stable) are assessed at sites where the species has more than five years of annual index data. Click on the green question mark next to the species name above for more details on how trends are calculated.
Links to lists of sites with particular statuses
• Extinct sites (7)
• Colonised sites (5)
- Stable sites (80)
- Declining sites (25)
- Increasing sites (13)
