18:04 16 December 2015
A study called State of the UK's Butterflies suggests that up to 76per cent of resident and regular migrant butterflies have declined.
A charity, Butter Conservation, said that some common species have suffered "major slumps."
The researchers have enlisted the help of thousands of volunteers to build up this long-term national picture.
The report was produced in cooperation of Butterfly Conservation and the Centre for Ecology & Hydrology (CEH), which encouraged the public to take part in surveys to help monitor trends in UK biodiversity.
Although the main conclusion of the report is about the growing threat to the lives of butterflies, the research also reveal that some rare species are benefiting from targeted conservation.
Richard Fox, of Butterfly Conservation, said: "It's about protecting these sites from being destroyed. Co-ordinated management of a landscape in a whole series of sites - that gives the butterflies a fighting chance."
The wider picture, however, is of decline. The study shows downward trends of some of UK's most common butterflies, which include the gatekeeper and the wall, a once common farmland butterfly in southern Britain.