In the middle of the 19th century, small animal advocacy groups began organizing for the first time. Today, many animal-welfare networks are large organizations with sufficient funds to bolster their good intentions. Some focus on abused pets, others focus on mistreated farm animals, others dedicate their time and resources to the protection of natural wildlife.
American Society for the Prevention of Cruelty to Animals
Founded in 1866, the ASPCA is the oldest animal-welfare organization in the Western Hemisphere, and is currently the largest animal or environmental charity in America. The ASPCA is independent from other SPCAs, and works to rescue abused animals, pass humane laws and share resources with shelters in the United States. The organization was the first to be granted police powers to investigate and make arrests in cases of crimes of against animals.
Humane Society of the United States
Founded in 1954, the Humane Society rescues and cares for tens of thousands of animals each year, but focuses on preventing abuse before it occurs. The group also works to affect public policy through animal advocacy, provides training and services to local shelters, works for corporate reform and provides pet owners with assistance and education in the care of their animals. The Humane Society advocates not only for pets and farm animals, but also for wildlife throughout the world.
National Wildlife Federation
The organization that would become the National Wildlife Federation was formed in 1936 as a group of anglers, hunters, outdoor enthusiasts and conservationists interested in protecting wildlife and their habitats. The organization still focuses on natural wildlife by advocating against carbon pollution and by lobbying law makers to pass legislation that serves those goals. It also advocates for the protection of wildlife by reducing dependence on traditional forms of energy and promoting the use of renewable energy.
World Wildlife Fund
The WWF works in 100 countries and is supported by nearly 5 million members, around 1.2 million of whom are in the United States. Its core mission is to advocate on behalf of wildlife, specifically protected and endangered species such as elephants, tigers, gorillas, giant pandas and rhinos. It works to fight illegal poaching and fishing, prevent habitat destruction and educate and improve the lives of human beings who coexist -- and often conflict -- with those species.