Dark Green Fritillary (Speyeria aglaja)
© - Nick Greatorex-Davies
The widespread Dark Green Fritillary is a species of Bracken hillsides and open flower-rich grasslands such as chalk downs, coastal grassland, dunes and sometimes woodland rides and glades. Eggs are laid on Marsh Violet (Viola palustris) or Hairy Violet (V. hirta), depending on the habitat, generally in taller herbaceous vegetation than some of its relatives. The butterfly its declining in parts of its range. (For further details on this species see http://www.butterfly-conservation.org/).
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). Further details on the analysis of UKBMS data can be found [here]
This chart shows the average number of butterflies seen on transects between April and October across all sites (fitted values from a Generalised Additive Model). The blue line gives average counts over the full BMS series (1976 to date) and the red line gives the average for the last year.
This map shows symbols for the mean abundance at transect sites, with the colour of the symbol reflecting the level of abundance. Means are over all years. Grey background squares are the occupied cells as shown by the Butterflies for the New Millenium over the previous ten year period.
