The Cache River National Wildlife Refuge is a 68,993 acre (223 km2) (2014) wildlife refuge in the state of Arkansas managed by the United States Fish and Wildlife Service (FWS). The refuge is one of the Ramsar wetlands of international importance under the Ramsar Convention signed in 1971. It is one of the most important wintering area for ducks and the largest remaining tract of contiguous bottomland hardwood forest on the North American continent. In 2005, a possible sighting of the ivory-billed woodpecker, thought to be extinct, brought attention to the refuge.