The dramatic 1° Celsius rise in global temperatures since industrialisation has already proved to have upended the lives of wild flora and fauna: that of at least 15,801 species on the Red List of Threatened Species, according to IUCN (International Union for Conservation of Nature).
Species have been driven to extinction, such as the migratory bird, the slender-billed curlew; reptiles, such as vibrantly-hued tropical lizards, now suffer ecological discoloration; and birds and mammals are changing their breeding pattern even in the Arctic, where a loss of sea ice has hugely impacted the Arctic seal’s ability to breed, driving it to near extinction.
Animals have had to adapt too, often through species redistribution. In the UK some birds have expanded their range, which is not great news as it is likely caused by habitat deterioration. As for fish, the pink salmon is increasingly migrating to Arctic rivers. The researchers found that anthropogenic climate change had redefined the geographic distribution of butterflies worldwide. The study found horizontal expansion among Araschnia levana , Boloria selene and P. aegeria .
For instance, data from 1,20,000 birdwatchers in 48 countries, published several years ago in The European Breeding Bird Atlas shows that in Europe, breeding birds have moved on average one km north every year in the past three decades, such as the pallid harrier. a new global study, published in Nature Ecology and Evolution by scientists from around the world, including India, have created the largest dataset to analyse 1,758 species of butterflies (about 10% of the world’s butterflies) across 105 countries While most studies have focused on birds and fish. As many as 19,000 species of butterflies exist globally. 27 per cent find their habitat has contracted While most species (80 per cent) have in fact expanded their territorial habitats.
Their defined host-plant associations, their high sensitivity to temperature, high dispersal capacity and short lifecycles, together, “render them a highly effective early warning system for detecting the biological impacts of climate changes,” says the paper. The cold-blooded butterfly is an excellent gauge of climate change: “Their well-characterized larval host-plant associations, high sensitivity to temperature, relatively high dispersal capacity and short lifecycles, together, render them a highly effective early warning system for detecting the biological impacts of climate change,” says the paper. Horizontal range expansion means that a species expands its range area without losing or gaining substantial altitude (the latter is a more well-known result of biological impacts of climate change), said co-author Krushnamegh Kunte of the National Centre for Biological Sciences in Bengaluru. “Horizontal range expansion may be a combination of good, bad and neutral from a species as well as human perspective,” he explained. The findings of climate-driven range shifts “call for concerted efforts to improve inclusive data monitoring and conservation efforts, especially for tropical countries, where human-induced land-use changes exert additional critical pressure.” the study said.
