The U.S. Fish and Wildlife Service (FWS) has been around for about twenty years in its current form. It is an amalgamation of other related organizations, the first of which, the U.S. Fish Commission, was established in 1871. It has worn many hats since then, sometimes environmental, sometimes aiding the big business that once was the fishing industry. It also got involved in the repopulation of the buffalo, which had been rendered nearly extinct during the “taming” of the Wild West. When the Endangered Species Acts of 1966 and 1973 were passed by Congress, the FWS overtook responsibility for protecting the nation's diminishing wildlife. Now the FWS is perhaps best known as the government agency that places plants and animals on the endangered species list.

These days the U.S. Fish and Wildlife Service maintains and administers more than 500 wildlife refuges, encompassing more than 92 million acres across the land, including the Caribbean. Typical work might involve keeping the landscape hospitable for the wildlife by removing alien nonnative plant and animal life, making sure creatures that graze have enough grass and water, and regulating the burning of overgrowth. Most of the lands under the service's jurisdiction are wetlands, though the FWS also controls the lush forests of the Pacific Northwest and Alaska. The FWS also manages fish hatcheries and research facilities.