Climate change drives global butterfly range shifts, study finds

Climate change presents animals and plants with a fundamental challenge: What can they do when their established habitats become increasingly warm? They can adapt to the changing conditions—or move to areas where the climate remains suitable for them.

Climate change is driving shifts in where butterflies are found globally, according to a major new study, with some species moving northwards or seeking out higher elevations in search of cooler conditions.

A global analysis of range-shift records for 1,758 butterfly species—10% of known butterfly species—found that 80% had expanded their range and that 79% of all recorded range shifts were linked to climate change and extreme weather events. The new study, published in Nature Ecology & Evolution, also reports range contractions for 27% of species, and 22% of species showed a change in elevation. Because many species exhibited multiple types of range shifts, the percentages for expansions, contractions and elevation changes are above 100%.

A global study of 1,758 butterfly species across 105 countries has found that butterflies are rapidly changing where they live as climate change reshapes habitats. While many species are expanding into new areas, others are losing parts of their traditional range. Researchers say these shifts are an early warning of wider ecosystem changes and stress the need for better global monitoring and conservation efforts.

In 32 of the countries included in a recent study, at least a quarter of the native butterfly species had moved to new areas.

Climate change is driving shifts in where butterflies are found globally, a major study has said, with many species moving into new areas while others are retreating from traditional habitats.

PARIS, France (AFP) — Climate change is driving shifts in where butterflies are found globally, a major study said Wednesday, with many species moving into new areas while others are retreating from traditional habitats. The study in Nature Ecology & Evolution is one of the most comprehensive to date on how butterfly distributions are changing, assessing more than 1,700 species across 105 countries and territories. Researchers found that nearly 80 percent of the reported shifts in the geographic ranges where butterflies were associated with climate change and extreme weather events. Other factors were also driven by human activity: changes in land use, intensive agriculture, urbanisation, habitat fragmentation and the introduction of invasive species. Butterflies are considered important indicators of ecosystem health because they are highly sensitive to temperature changes, have short life cycles and depend on specific host plants. As the planet warms -- primarily because of the burning of coal, oil and gas -- some butterfly species are relocating northwards or seeking out higher elevations in search of cooler conditions. However, just 22 per cent of species showed a shift in elevation. Overall, 80 per cent of species expanded their range while 27 per cent experienced range contractions, with some showing different patterns in different regions, underscoring the complexity of responses to climate change. "This is rather good news as it proves that butterfly species are capable of migrating and shifting their range to adapt to changes," study co-author Jonathan Lenoir, an ecologist from France's national scientific research centre (CNRS), told AFP. Lenoir cautioned that range expansions were easier to detect than contractions because it was simpler to confirm a species has colonised a new area than prove it has vanished entirely from another. Many observations, including those made by citizen scientists, were concentrated in lowland areas and near urban centres, potentially skewing the findings. But butterflies could only adapt so far, Lenoir said. It was possible that beyond a certain warming threshold more butterflies would contract their range, causing "much more rapid and sudden upheavals" among certain species and "potential extinctions". A 2024 study in Global Ecology and Biogeography found that 84 per cent of roughly 270 butterfly species studied in Europe would reduce their range by 2080 if global temperatures keep rising. "Some butterfly species will not necessarily be able to migrate further north in latitude, or higher up in the mountains, in response to the global rise in temperatures," said Lenoir. Species endemic to mountain regions on islands could become "trapped" as their habitat is reduced "to almost nothing" with limited options to shift elsewhere, he added. The authors advocated for stronger conservation policies, the protection and restoration of butterfly habitats, ecological corridors and microclimatic refuges, and improved biodiversity monitoring, particularly through citizen science. Underlining it all, they emphasised the urgent need to limit global warming to lower levels. Knowledge gaps, too, must be addressed: just one in 10 butterfly species has documented data on how its range is changing and tropical regions remain largely understudied, the authors added.

New research shows early-warning species is on the move, expanding or contracting geographic range and changing altitudeButterflies, often considered a “sentinel of change”, are on the move across every continent they inhabit, shifting to survive as global heating reshapes their environment.About one in 10 species have already expanded or contracted their geographic range, or shifted in altitude, according to a global study published in Nature Ecology & Evolution. Continue reading...

Conservation cannot only protect habitats where species once lived – it must include the places where they will relocate in a warming world.