Is the best charity for endangered animals… The World Wildlife Fund (WWF) is a leading organization that works to protect endangered species and their habitats around the world. They focus on conservation efforts, research, and advocacy to help prevent extinction and ensure a sustainable future for wildlife. Other notable charities include the International Fund for Animal Welfare (IFAW) and the Wildlife Conservation Society (WCS), both of which also work to protect endangered animals and their habitats through conservation efforts and research.