Aransas National Wildlife Refuge, originally known as Aransas Migratory Waterfowl Refuge, is located on Blackjack Peninsula, eight miles southeast of Austwell and midway between Rockport and Port Lavaca, on the Gulf Coast. The refuge comprises 54,829 acres of scattered blackjack oak woodlands, fresh and saltwater marshes, ponds, and coastal grasslands on the mainland, as well as 56,668 acres on Matagorda Island. Karankawa, Lipan, Tonkawa, and Comanche Indians once occupied the area. The refuge occupies land on which it is believed pirate Jean Laffite buried treasure. In 1937 surface rights to what was by then the St. Charles Ranch of San Antonio oilman Leroy G. Denman were purchased by the government with funds raised from the sale of migratory bird stamps, and the refuge was established on December 31, 1937, with 47,261 acres on the Blackjack Peninsula. Continental Oil Company won the right to extract oil and gas within the refuge. In 1967 the refuge acquired an additional 7,568 acres along St. Charles Bay; it also purchased 19,000 acres on Matagorda Island in 1982 and another 11,502 acres in 1986. Another 2,940 acres of the island was added to the refuge in 1993.
The refuge forms a unit in the Central Flyway, which extends from Alaska and Arctic Canada southward. It provides wintering grounds for the rare whooping crane, 320 species of other birds including wild turkeys and Canadian geese, and thirty-seven species of mammals. Among the inhabitants are deer, armadillos, javelinas, and alligators. Facilities at the refuge include an observation tower, a picnic area, a car tour route, walking trails, and an environmental study area. Hunting for deer and feral hogs is permitted in season. The refuge on the mainland is administered by the United States Fish and Wildlife Service, Department of the Interior; Matagorda Island State Park is managed by the Texas Parks and Wildlife Department as a unit of the National Wildlife Refuge System. In the late 1980s the refuge was losing about twenty-five acres of shoreline each year as a result of erosion. By 1991 volunteer projects had succeeded in stabilizing 4,785 feet of shoreline, but the problem was still not solved.