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Dark Green Fritillary (Argynnis 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/).
Family: Nymphalidae
Status: Rapid increase
Status details:
Status since 1976 is Rapid increase with an increase of 109%
Status over the last 20 years is Rapid increase with an increase of 240.1%
Status over the last 10 years is Stable with an increase of 53.1%
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 data show large fluctuations but no significant overall trend, but at most individual sites the species has either noticeably declined or noticeably increased but there is no apparent pattern in these changes which are likely to be due to changes in the habitat due to management or neglect.
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, Dark Green Fritillary has been recorded from 410 transects in the Butterfly Monitoring Scheme. Of these, annual indices of abundance have been calculated from 448 sites, with an average index of 14 individuals per site.
For 224 of these sites, Dark Green Fritillary has been recorded well enough to calculate annual indices of abundance in 6 or more years, allowing trends to be calculated.
In 2006, 8072 individuals were recorded from 166 sites, producing annual indices at 140 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 (11)
• Colonised sites (10)
- Stable sites (79)
- Declining sites (17)
- Increasing sites (22)
