Conservation efforts are bringing species back from the brink, even as overall biodiversity falls

A major review of over 67,000 animal species has found that while the natural world continues to face a biodiversity crisis, targeted conservation efforts are helping bring many species back from the brink of extinction.

The study draws on data from the IUCN Red List, the world’s largest database of species conservation status. The researchers say their results, reported in the journal PLOS Biology, highlight both the successes and the need for urgent action.

The world is facing a global biodiversity crisis, with 28% of more than 160,000 assessed species threatened with extinction, and an estimated one million species facing this fate due to human activities. However, conservation measures can be successful if there is concrete evidence about what works.

The researchers, led by the University of Cambridge with the IUCN, BirdLife International, and Oxford and Durham Universities, used Red List data to assess whether conservation measures had been put in place, and whether those actions had a positive impact on a given species’ conservation status.

“We found that almost all the species that have moved from a more threatened category to a less threatened category have benefited from some sort of conservation measures,” said lead author Ashley Simkins, a Ph.D. candidate in Cambridge’s Department of Zoology. “It’s a strong signal that conservation works.”

While there is no ‘one size fits all’ solution, the researchers observed some connections between conservation success stories. Many of these species live in isolated areas, such as islands, where intensive conservation efforts—such as habitat protection, captive breeding and reintroductions—can be fully implemented.

“While biodiversity loss is a genuine crisis, it’s vital that we celebrate the success stories wherever and whenever we can,” said Simkins. “It’s so hard for a species to improve its conservation status, but with the right effort, we can turn things around.”

The Iberian lynx, once the world’s most endangered cat, has rebounded from just a few hundred individuals to a few thousand. Likewise, the kākāpō, a flightless parrot from New Zealand, has benefited from dedicated recovery programs. And the European bison, which was hunted to extinction in the wild in the early 20th century, now roams parts of Eastern Europe thanks to sustained conservation efforts over decades.

Marine species have also seen dramatic recoveries. Humpback and blue whales, once driven to the brink of extinction by commercial whaling, have made a comeback after an international moratorium on whaling. However, despite these success stories, the study found that six times more species are declining than improving.

The researchers say that, like human health care, preventative measures in conservation are preferable and more cost-effective to emergency interventions.

“Humans have gotten pretty good at what could be considered ‘A&E’ conservation—focusing on species at very high risk of extinction,” said Simkins. “What we’re less good at is preventing species from becoming threatened in the first place. We need to move beyond treating the symptoms of biodiversity loss and start addressing the root causes.”

The researchers also emphasize the need for collaborative, locally driven conservation. In Papua New Guinea, for example, conservationists worked with local communities to replace tree kangaroo hunting with sustainable forms of animal protein, including farming of chickens and fishing—an approach that benefitted both people and wildlife.

“It’s vital that we as conservationists are working with stakeholders, rather than dictating to them, whether that’s an Indigenous community in Papua New Guinea or a farmer in Somerset,” said Simkins.

“Conservation doesn’t have to be a zero-sum game—there are compromises that can benefit both the natural world and human society.”

“In this climate of constant stories about wildlife declines and insufficient political action to protect nature, it’s important to realize that there are also many success stories and that conservation efforts are making a real, demonstrable impact on the world,” said co-senior author Dr. Silviu Petrovan, also from the Department of Zoology. “Conservation works if given the chance.”

“This research sheds light on which actions to save species have been effective, and what interventions are needed,” said co-author Dr. Stuart Butchart, Chief Scientist at BirdLife International. “Governments need to turn their words into actions, and rapidly scale up efforts to save species from extinction and help populations to recover. Safeguarding our natural heritage for future generations depends upon this.”

“The IUCN Red List of Threatened Species informs and guides on-the-ground conservation decisions; actions which are further guided by the research presented in this publication,” said co-author Craig Hilton-Taylor, Head of the IUCN Red List.

“Almost everyone will have their own favorite example of a conservation success story, whether it’s the bald eagle in North America, or the red kite in the UK,” said Simkins. We need joint action to ensure these positive stories aren’t the exception—they’re the norm.”