By 1987 only 27 California condors were left in the world, and every one of them was in a zoo. The decision to capture the last wild bird was bitterly controversial. Some people argued that a condor in a cage was no longer really a condor. Others said that without capture there would soon be none at all. That tension runs through all of conservation.
Why conserve?
People defend biodiversity for different reasons: for the food, medicine, clean water and pollination it supplies; for its beauty and its place in cultures and faiths; and because many believe other living things have value in themselves. Ecology adds a practical point. Conservation succeeds or fails through people, and the people who live closest to wild places are often among the poorest. How their rights and livelihoods are treated is part of whether conservation is just, and part of whether it works.
Protected areas
Yellowstone, created in 1872, is widely regarded as the world's first national park. Its model shaped conservation for a century. That model is sometimes called fortress conservation: protecting nature by drawing boundaries and keeping people out. Supporters point out that strictly protected areas have saved many species and that studies often find less forest loss inside them than outside. Critics point to the human cost. Native peoples were pushed out of Yellowstone, and in many parts of Africa and Asia, communities were evicted to create parks. Others worry about paper parks, protected areas that exist on maps but lack funding or enforcement.
In December 2022, nearly every country in the world adopted the Kunming-Montreal Global Biodiversity Framework. Its best-known target, often called 30 by 30, is to conserve 30 percent of the world's land and 30 percent of its oceans by 2030, while respecting the rights of Indigenous peoples and local communities. Current coverage falls well short, especially at sea, and debate continues over whether quality and management matter more than the size of the area on a map.
Saving one species at a time
Laws such as the US Endangered Species Act of 1973 protect listed species and their critical habitat. The law helped bring the bald eagle back from near loss in the lower 48 states. Captive breeding has rescued species with almost no wild members left, such as the condor. Critics argue that such efforts are costly, often begin too late, and can provoke landowners who fear restrictions. Supporters reply that saving a species also protects its habitat. The condor shows the limits of rescue without a cure: the main ongoing threat to wild condors is lead poisoning from ammunition fragments in the carcasses they eat.
Rewilding
In the 1990s the American biologists Michael Soulé and Reed Noss proposed a bolder approach, built on large core reserves, corridors connecting them, and the return of big carnivores. Rewilding means restoring natural processes, often by reintroducing missing species, and then stepping back from intensive management. In England, the Knepp estate turned intensive farmland over to free-roaming cattle, pigs and ponies, and rare birds such as nightingales and turtle doves returned. Beavers are back in parts of Britain after an absence of centuries. Rewilding has costs and risks. At the Oostvaardersplassen reserve in the Netherlands, large herds of deer, cattle and horses were left to regulate themselves inside fences. In the harsh winter of 2017 to 2018 thousands of animals starved or were culled, causing a public outcry.
Indigenous stewardship
A 2018 study found that Indigenous peoples manage or hold tenure rights over at least a quarter of the world's land, much of it relatively intact. Studies in the Amazon and elsewhere often find lower deforestation in Indigenous territories with secure land rights than on comparable unprotected land. In northern Australia, traditional early dry season burning has reduced the large, hot fires that come later in the year. Supporters argue that recognizing land rights is both just and effective. Two cautions keep the case honest. A widely repeated claim that Indigenous lands hold 80 percent of the world's biodiversity lacks a solid data source, as researchers who traced it in 2021 reported. And Indigenous communities are not uniform; they face their own economic pressures and make their own choices, which outsiders should not romanticize.
Worked example: the California condor
Condors once soared from British Columbia to Mexico. By the twentieth century, shooting, poisoning, the pesticide DDT and lead from bullets in carcasses had driven them close to extinction. After the last wild birds were captured in 1987, zoos in San Diego and Los Angeles bred them, and releases began in 1992. The population has since grown to several hundred, more than half of them flying free in California, Arizona, Utah and Mexico. In 2022 the Yurok Tribe began releasing condors in northern California. Yet many wild condors must still be caught for blood tests and treated for lead poisoning, and California fully banned lead ammunition for hunting only in 2019. The condor is a success, but it shows that saving a species without removing the cause of its decline can turn conservation into permanent life support.