Tijuana Slough National Wildlife Refuge is located in the most southwestern corner of the contiguous United States. As a National Wildlife Refuge, it is administered by the U.S. Fish and Wildlife Service. It was established in 1980. The refuge forms the northern part of the Tijuana River National Estuarine Research Reserve, one of 22 National Estuarine Research Reserves created nationwide to enhance scientific and public understanding of estuaries, and thereby contribute to improved estuarine management. It is also part of the San Diego National Wildlife Refuge Complex.