Butterflies around the world are increasing their distribution range due to climate change in far greater and more complex ways than previously understood, according to an international team of researchers.
Forrest Fellow Dr Upama Aich, from The University of Western Australia’s School of Biological Sciences, was co-author of the study led by Monash University, which revealed that one in 10 butterfly species globally had shifted its distribution range.
Published in Nature Ecology & Evolution, the study analysed 6,182 range‑shift records for 1,758 species across 105 countries, drawing on English and non‑English scientific literature as well as 68 expert assessments.
“We found climate‑driven redistribution is not a future scenario but a current and accelerating one, which requires new conservation strategies capable of responding to species on the move,” Dr Aich said.
Researchers found climate change and extreme weather drove nearly 80 per cent of the butterflies’ expanded ranges, with many moving into newly suitable areas as temperatures rose.
At the same time, 27 per cent contracted their ranges, and 22 per cent shifted elevational range, though this shift in range in tropical species were rarely documented – concerning given the narrow thermal limits of tropical species.
Lead author Dr Shawan Chowdhury, head of the Global Change Ecology Lab at Monash University, said the findings exposed a rapidly changing natural world and revealed major blind spots in how biodiversity change was monitored.
“We found butterfly species shifting their ranges on every continent at an astonishing scale and it’s happening far beyond the well‑studied regions of Europe and North America,” Dr Chowdhury said.
When the researchers looked at how many species in each country had documented range shifts, five European countries stood out: the Czech Republic, Finland, Luxembourg, Spain and Sweden, and each had records for more than half of its butterfly species.
Looking only at species known to shift their ranges within that country or elsewhere, 32 countries had documented shifts for at least a quarter of their known butterfly species and 10 countries for more than half.
The research highlighted severe geographic gaps in Central Africa, Southeast Asia, New Guinea and the Amazon Basin, where records showing pattern of distribution shifts are missing despite being global biodiversity hotspots.
“Without equitable, standardised and multilingual biodiversity monitoring, conservation efforts risk being guided by an incomplete and biased evidence base,” Dr Aich said.