Sheltered pockets of cool habitat in the British countryside could come to the rescue of species threatened by climate change, say scientists.
Hummocky hillsides and shaded valleys provide local “microclimates” in which vulnerable flora and fauna can seek refuge, research suggests.
After analysing five million records of plants and animals collected by members of the public, experts concluded that a number of these sheltered spots or “refugia” are already being used by species sensitive to warming.
They include butterflies, beetles and plants that have started to disappear from the warmer parts of their geographical range.
By the end of the century, many native British species will be experiencing intolerable temperatures, forcing them to move northwards and uphill, say the researchers.
Lead scientist Dr Andrew Suggitt, from the University of York, said: “It is tempting to think it might be quite nice for the UK to warm up by a few degrees, but this will actually be really bad news for many of our native animals and plants that are adapted to our cooler, wetter climate.
“However, refugia within the varied topography of the British landscape can have a local temperature difference of as much as seven degrees in daytime maximum temperature, making them extremely important alternative habitats for many climate-sensitive species.”
For some species, the benefits of local refugia could be substantial, say the researchers.
They estimate that refugia had reduced the likelihood of regional extinctions of dark green fritillary butterflies by 63%.
Another insect species, the wood tiger moth, was 65% more likely to survive the effects of global warming in refugia.
Microclimate refugias could be artificially created in regions where there is little variety in local conditions, such as the flat fens of East Anglia, said the scientists.
It was also important that natural refugia are protected, said Dr Suggitt.
Research director Dr Ilya Maclean, from the University of Exeter, said: “The public can also do their bit by encouraging a good mix of sunny and shady spots in their gardens, and by planting species that offer a lot of cover alongside those that offer less.
“Now that we know a substantial amount of warming will unavoidably take place this century, it’s about giving our plants and animals as many options as possible to avoid the adverse heat.”
Co-author Dr Mike Morecroft, from the Government conservation body Natural England, said the study had provided evidence that refugia can “make a real difference to the fate of species threatened by climate change”.
He added: “We now have a good understanding of where they are and which species most need the lifeline they provide. We’re working to incorporate this new knowledge into our conservation planning and management.”
