Unchecked climate change could destroy the natural wonders of the world’s ‘biodiversity hotspots’, scientists warn
Many animals and plants unique to the world’s most stunning natural places face extinction if greenhouse gas emissions continue to rise, according to a new scientific study published in the journal Biological Conservation. However, remaining within the climate goals of the Paris Agreement - which aims to keep global heating well below 2°C, ideally at 1.5°C - would save the majority of species.
A global team of scientists, including Tyndall Centre's Jeff Price and Rhosanna Jenkins, analysed almost 300 biodiversity hotspots - places with exceptionally high numbers of animal and plant species - on land and at sea. Many of these hotspots contain ‘endemic’ species, unique to one geographic location such as one island or one country.
They found that if the planet heats by over 3°C then a third of endemic species living on land, and about half of endemic species living in the sea, face extinction. On mountains, 84% of endemic animals and plants face extinction at these temperatures, while on islands that number rises to 100%. Overall, 92% of land-based endemic species and 95% of marine endemics face negative consequences, such as a reduction in numbers, at 3°C. Current policies put the world on track for around 3°C of heating.
Stella Manes, lead author of the study and a researcher at the Federal University of Rio de Janeiro, said, “Climate change threatens areas overflowing with species that cannot be found anywhere else in the world. The risk for such species to be lost forever increases more than ten-fold if we miss the goals of the Paris Agreement.”
“Biodiversity has more value than meets the eye. The greater the diversity of species, the greater will nature's health be. Diversity also protects from threats such as climate change. A healthy nature provides indispensable contributions to people, such as water, food, materials, protection against disasters, recreation, and cultural and spiritual connections," Stella added.
Endemic species include some of the world’s most iconic animals and plants. Endemic species threatened by climate change include all species of lemur, which are unique to Madagascar; the blue crane, which is the national bird of South Africa; and the snow leopard, one of the most charismatic animals of the Himalayas.
The study found that endemic species are 2.7 times more likely to go extinct with unchecked temperature increases than species that are widespread, because they are only found in one place; if climate change alters the habitat where they live, they are gone from the face of the Earth. If greenhouse gas emissions keep rising then places like the Caribbean islands, Madagascar, and Sri Lanka could see most of their endemic plants go extinct as soon as 2050. The tropics are especially vulnerable, with over 60% of tropical endemic species facing extinction due to climate change alone.
"Our results indicate that endemic species from rich-spots are at much higher vulnerability than non-endemics compared to global averages, which reinforces their priority for conservation actions," said Rhosanna Jenkins, researcher at the Tyndall Centre for Climate Change Research, University of East Anglia and author of the study.
But all is not lost. If countries reduce emissions in line with the Paris Agreement then most endemic species will survive. In total, just 2% of endemic land species and 2% of endemic marine species face extinction at 1.5ºC, and 4% of each at 2ºC. Strong commitments from global leaders ahead of the climate change summit in Glasgow later this year could put the world on track to meet the Paris Agreement, and avoid the widespread destruction of some of the world’s greatest natural treasures.