More than 80 percent of the world's species live in forests
Forests shelter the great majority of known species, so clearing them wipes out homes on a vast scale while also feeding climate change. Deforestation is only one of many pressures conservationists fight, alongside poaching, overfishing, pollution and acidifying oceans. Among assessed species, the IUCN counts 42,100 at risk of extinction.
Wildlife conservation aims to protect wild species and their habitats so that populations stay healthy and ecosystems are restored or enhanced. The scale of the problem depends on how you count: the IUCN's figure covers only species it has assessed, whereas a 2019 UN biodiversity report, extrapolating to all life, put the number at risk at around a million. International treaties such as CITES in 1973 and the Convention on Biological Diversity in 1992 try to coordinate a response, backed by groups including the Nature Conservancy, WWF and Conservation International.
Habitat loss is the leading driver. Farming, logging and urban growth shrink the places wildlife can live, while fragmentation chops continuous land into islands. Smaller patches hold smaller populations, and smaller populations are likelier to die out; they also bring animals into more frequent conflict with people. Tropical forests such as the Amazon, the richest biome of all, face the heaviest pressure. Some laws push back, among them the US Wilderness Act of 1964, which set aside protected wild areas.
Taking too much is another threat. Overexploitation means harvesting faster than a species can replace itself, and a century of heavy fishing for predators such as tuna and salmon has left the fish both fewer and smaller. Poachers target the rarest animals precisely because rarity raises prices: elephants for ivory, tigers for skins and rhinoceroses for horn, plus protected plants and animals sold as pets, food or souvenirs.
The oceans face a chemical problem. Seawater normally absorbs carbon dioxide and stores it deep down through a process called the biological pump. Higher emissions, along with stronger layering of the water that slows the pump, are lowering ocean pH. Corals and other calcifying organisms suffer most, and mass bleaching destroys habitat for the many creatures that depend on reefs. Fossil corals and ice cores suggest acidification in the distant past, probably slower, coincided with extinction events.
Source: Wildlife conservation
