Margaret Vickery organises the annual Garden Butterfly Survey. Read Margaret's summary of results from 2013 below. For a comparison of data from the last three years view this table of results.
A Year of Contrasts
2013 was certainly a year of contrasts, with a harsh winter, mediocre, late spring and then one of the most glorious summers/autumns for many years. This weather pattern was reflected in the percentage of butterflies recorded in gardens, with the spring species showing decreases and some summer/autumn species showing unprecedented increases.
Orange Tip showed an overall 1% reduction in the percentage of gardens visited compared with 2012 but the number having a visit in June increased by 18%.The Holly Blue, which lays eggs in the spring, was down 17%, while few Red Admirals were seen in spring, probably because the harsh winter had killed hibernating adults, and this was not remedied by later migrations, resulting in a drop of 6% compared with 2012.
There was a 20% overall increase in the number of species seen in gardens with 42% recording 15 or more compared with 22% in 2012. This was undoubtedly due to the warm, sunny weather in summer/autumn, which enabled butterflies to travel easily from their breeding grounds. Eighteen species showed an increase in the number of gardens visited compared with 2012 (see table). Such an enormous improvement has not happened before in the many years of the garden butterfly survey. Those with the most spectacular rises included Small Skipper (16%), Small Tortoiseshell and Common Blue (14%), Small Copper and Ringlet (12%), and Brimstone and Green-veined White (11%). It is particularly pleasing that all the least widespread species showed notable increases, even the Wall (6%).
Rarer Garden Visitors
Marbled White records increased from 9% of gardens in 2012 to 15% in 2013, while a staggering 13% of gardens had one or more visits from Silver-washed Fritillary, which was more than from Clouded Yellow (12%). I noted in 2010 that this fritillary seemed to be increasing garden visits and as can be seen from the chart this has continued. Twenty one other species were recorded, notably Brown Argus, Dark Green Fritillary, Purple Hairstreak and Essex Skipper which all visited 30 or more gardens out of the 1,310 which were recorded.
Scotland and Wales
There were huge contrasts between some butterfly visitors in Scotland and Wales (see table). For example Orange Tip increased by 6% in Scotland but decreased by 1% in Wales, while Common Blue decreased by 6% in Scotland but increased by14% in Wales.
Small Tortoiseshell Update
Although the SE corner still lags behind the rest of the country in seeing Small Tortoiseshell in gardens, the difference was only 9% in 2013 compared with 20% in 2012, so there is hope on the horizon and I can look forward to the day when there will be no need to continue with the yearly update on the fate of this quintessential garden species.
Thank you to all who recorded last year. Forms for this year were sent out with the spring Butterfly but if you require a replacement I can send this electronically (margaretvickery73@virgin media.com). This year is the 25th anniversary of my involvement with the national garden butterfly survey, so I hope many members will join in the celebration by sending in their records next December.