A significant portion of Earth’s biodiversity faces extinction by the end of the century if current greenhouse gas emissions continue unchecked, according to findings published in Science on December 5. The study, which reviewed over 450 research papers spanning 30 years, highlights the escalating threat climate change poses to global species, particularly amphibians and those in mountain, island, and freshwater ecosystems. The analysis draws attention to the urgent need for targeted conservation efforts and stricter climate action.

Climate Change and Rising Extinction Risks

The research, conducted by Mark Urban, a biologist at the University of Connecticut, analysed the impact of various warming scenarios on species survival, as per reports. The findings suggest that maintaining global temperature increases below 1.5 degrees Celsius, as outlined in the Paris Agreement, could limit extinction risks. However, a rise of 1.5 degrees Celsius could still place approximately 180,000 species — 1 in 50 worldwide — at risk of extinction.

The study warns that if temperatures increase by 2.7 degree Celsius, the risk doubles, with 1 in 20 species potentially facing extinction. Higher warming scenarios, such as a 4.3 degree Celsius rise, project a nearly 15 percent extinction rate, escalating to almost 30 percent if temperatures climb to 5.4 degree Celsius.

Amphibians and Ecosystem Vulnerability

According to Urban, in a statement, amphibians are particularly vulnerable due to their reliance on stable weather patterns for their life cycles. Ecosystems such as those in South America, Australia, and New Zealand are also identified as hotspots for extinction risks because of their isolation, making migration and adaptation difficult for native species. He told Live Science that ecosystems like mountains and islands are especially affected because surrounding habitats are often unsuitable for migration.

Call for Policy and Conservation Action

The study underscores the necessity of global policy efforts to curb emissions and protect ecosystems. Urban emphasised that the findings eliminate uncertainty about climate change’s impact on species extinction, urging policymakers to act decisively.

 

Five Hawaiian crows, also known as ʻalalā, which went extinct in the wild in 2002, were released on Maui for the first time on Wednesday as part of a conservation effort to restore the species to its natural habitat, officials said.
Described as intelligent and charismatic, these birds are the last surviving species of Hawaiian crow, previously found only on Hawaii’s Big Island, according to the San Diego Zoo Wildlife Alliance.
Their extinction in the wild was driven by habitat loss, invasive predators, and diseases, conservationists noted.
According to the Associated Press, the vice president of conservation science at San Diego Zoo Wildlife Alliance, Megan Owen said, “The translocation of ʻalalā to Maui is a monumental step forward in conserving the species and a testament to the importance of partnership in reversing biodiversity loss.”
This release reflects years of collaboration amongst organisations, including the US Fish and Wildlife Service, State of Hawaii Department of Land and Natural Resources Division of Forestry and Wildlife and the University of Hawaii, she added.
The released group comprised two females and three males, who developed strong social bonds at Keauhou and Maui Bird conservation centres.
The San Diego Zoo Wildlife Alliance conducted thorough assessments of the birds for release based on their ability to forage for food and respond to predators, with veterinarians conducting thorough health assessments.
Between 2016 and 2020, thirty ʻalalā were released in the Big Island’s Puu Makaala Natural Forest Reserve. However, despite early success, the population declined, prompting officials to halt reintroduction efforts.
The remaining were subsequently brought back into human care.
Keanini Aarona, the avian recovery specialist at Maui Bird Conservation Center said, “To me, and in my culture, the ʻalalā are like our ancestors – our kūpuna. The forest wouldn’t be there without these birds.”
“It means a lot to me to care for the ʻalalā,” Aarona added.