BUTTERFLY species once found in the south of England are now moving north to Scotland as climate change makes these areas more habitable.
While three-quarters of UK butterflies showed a 10-year decrease in either their distribution or population levels, a minority of common species such as the Peacock, Comma and Speckled Wood have continued to spread northwards.
However, endangered species are losing out because their populations are already in decline and unable to migrate.
They include the High Brown Fritillary, Duke of Burgundy and Pearl-bordered Fritillary, which face extinction.
Research by the University of York found only butterflies whose populations are stable or increasing have managed to expand and thrive in the new environments. Researchers warn the future survival of many of Britain's butterfly colonies depends on reversing population decline now in order to protect wildlife as the climate and landscape changes.
For the first time, a significant decrease in the total numbers of wider countryside butterflies have been recorded. The abundance of these common "garden" butterflies dropped by 24% over 10 years.
However, there is some positive news as a few threatened species such as the Heath Fritillary, Large Blue, Marsh Fritillary and Silver-studded Blue have increased or stabilised due to intensive conservation effort over the past decade.
The climate in Britain has warmed over the last four decades and many species, including butterflies, have shifted northwards.
Louise Mair, a PhD student in Biology at York, used data collected by members of the public and found species that were previously restricted to southern England are colonising in northern England and Scotland.
Butterflies have extended their distributions in this way because warmer climates have made northern regions increasingly more hospitable for these temperature-constrained insects.