The 900-acre Bandon Marsh NWR IBA at the mouth of the Coquille River consists of the Bandon Marsh Unit and the newly restored (2011) areas in the Ni-les'tun Unit east of I-101. This site contains the largest remaining tract of salt marsh in the Coquille River Estuary and is considered an important migratory stopover site along the Pacific Coast for migrating shorebirds. Other habitats present include mudflats, sloughs, and riparian Alder forest.
This may be the premium shorebird site on the Oregon Coast. Thousands of shorebirds of numerous species are routinely found here, with peak counts including 75,000 Western Sanpipers, 6,000 Dunlin, 2,500 Least Sandpiper, 2,000 Short-billed Dowitcher. Additional sightings include Semipalmated Plover, Black-bellied Plover, Pacific Golden Plover, Red Phalarope, Whimbrel, and rarities like Ruff.
Invasive plants including gorse, scotch broom, and english ivy are present on higher grounds. Mechanical removal is ongoing.