11% drop in Big Butterfly Count sightings

Ggatekeepers were top of the league this summer.

Butterflies hit by poor summer weather

September 2011. More than 300,000 butterflies and moths were counted during the Big Butterfly Count 2011.  Butterfly numbers were down this summer. The average number of individual butterflies and moths seen per count dropped by 11 per cent compared to last year's event. Many species were less abundant. The dismal summer weather, the coldest in nearly 20 years, was undoubtedly to blame. Butterflies need warm conditions to be active, find food and mates and, if female, to lay eggs. 

Common Blue numbers down 61%
The Common Blue suffered one of the biggest declines compared with 2010; its numbers fell by 61 per cent. Other species faring badly included the Brimstone, Small Copper, Comma and two common immigrants, the Painted Lady and Silver Y moth.

Gatekeeper top of the charts
The Gatekeeper topped the Big Butterfly Count chart this year, up from third place in 2010. Also moving up this year were the Red Admiral, which was almost twice as common in 2011 than last year, and the Speckled Wood, which increased by 80 per cent.

34,300 particpants
Although not a great summer for butterflies, there was a phenomenal response to the Big Butterfly Count this year, with 34,300 people taking part and twice as many counts submitted as in 2010. Many thanks to everyone who helped us ‘take the pulse of nature'.

See the full results and find out how all the species fared in 2011 on the Big Butterfly Count results page.