The small tortoiseshell saw a 47 per cent drop in numbers while peacock butterflies slumped to their second worst year on record, with a drop of 42 per cent on 2015 numbers. Sightings of comma butterflies fell 46 per cent while gatekeeper populations were down 40 per cent and small coppers dropped 30 per cent compared to 2015.Sir David, who is president of the charity, said: “Worryingly, we are now seeing the fortunes of some of our once common butterflies mirror those of our rarest species and they too are now also suffering significant declines with butterflies declining more rapidly in urban areas than in the countryside.“In the last decade our butterflies have experienced several poor years and although resilient, they simply cannot sustain repeated losses, especially if the habitats they need in order to rebuild their populations are also under threat.” Sir David Attenborough is encouraging members of the public to count butterflies over the next three weeksCredit:Helen Atkinson A large white butterfly Credit:Butterfly Conservation Sir David Attenborough has urged Britons to take time to count butterflies this month over fears that even common British species are dying out.Today marks the annual launch of the Big Butterfly Count, which encourages the public to look for 18 common species such as the Small Tortoiseshell, Peacock, Meadow Brown and Gatekeeper which are struggling.More than three-quarters of the UK’s butterflies have declined in the last 40 years, according to the charity Butterfly Conservation, and last year saw some saw the worst falls for butterfly numbers since the Big Butterfly Count began in 2010. This year’s count follows new findings that butterflies are declining more rapidly in urban areas than in the countryside.Richard Fox, Butterfly Conservation Head of Recording said: “With increasing numbers of our common and widespread butterflies in long-term decline, Big Butterfly Count is more important than ever. Simply taking 15 minutes out of your normal day to enjoy the sunshine and count butterflies can help us monitor their populations. It’s a win-win for wildlife.” Sir David added: “Taking part in the Big Butterfly Count is good for butterflies and it is also good for us all. The Count is good for butterflies because your sightings will tell us which species need help and in which areas we need to help them.“But the Big Butterfly Count is also good for you because 15 minutes spent watching butterflies in the summer sunshine is priceless; spending time with butterflies lifts the spirits and reinvigorates that sense of wonder in the natural world.”The Count runs from 14 July to 6 August. Taking part in the Count is easy – find a sunny spot and spend 15 minutes counting the butterflies you see and then submit sightings online at www.bigbutterflycount.org or via the free Big Butterfly Count app. A Red AdmiralCredit:Butterfly Conservation Want the best of The Telegraph direct to your email and WhatsApp? Sign up to our free twice-daily Front Page newsletter and new audio briefings.