St. Johns National Wildlife Refuge in Florida lies off State Road 50 west of Titusville and encompasses 6,255 acres, about 25 square kilometers. Established in 1971, it was created to protect the dusky seaside sparrow, Ammodramus maritimus nigrescens, a species that has since become extinct. The refuge is now administered as part of Merritt Island National Wildlife Refuge, connecting it to a broader federal system of protected lands in the region. Its significance rests in its role within that conservation network and in the history of efforts to preserve a vanished bird.