What are the threats?
• 99% of threatened species are at risk from human activities. Humans are the main cause of extinction and the principle threat to species at risk of extinction. • Habitat loss and degradation are the leading threats. They affect 86% of all threatened birds, 86% of the threatened mammals assessed and 88% of the threatened amphibians. • Introductions of alien species. Some of the worst include. cats and rats, green crabs, zebra mussels, the African tulip tree and the brown tree snake. Introductions of alien species can happen deliberately or unintentionally, for example, by organisms “hitch-hiking” in containers, ships, cars or soil. • Over-exploitation. Resource extraction, hunting, and fishing for food, pets, and medicine threatens many species. • Pollution and disease . • Human-induced climate change is increasingly recognised as a serious threat. Climate change is altering migratory species patterns, causing coral bleaching, etc.
