The refuge is administered from offices in King Salmon, Alaska and was established to conserve Alaskan brown bears, caribou, moose, marine mammals, shorebirds, other migratory birds and fish, and to comply with treaty obligations.
The Firth of Thames is an important site for waders or shorebirds, and is listed as a wetland of international importance under the Ramsar Convention.
Shorebirds such as the Black Turnstone and Ruddy Turnstone frequent the island as do garden birds such as the Ruby-crowned Kinglet, Golden-crowned Kinglet, Thrushes, Warblers, Pileated Woodpeckers, and Flickers.
No fish live in the alkaline waters of the lake; however, its dense population of brine shrimp supports a variety of shorebirds.
The ash lagoons have provided a roost site for gulls, shorebirds and terns; while the seawall provides excellent views of the flocks of sea ducks such as Common Eider, Velvet Scoter, Red-breasted Merganser, Long-tailed Duck and Common Goldeneye.
It inhabited the freshwater or brackish lakes that had in its time formed in today's Green River valley due to the uplift of the Rocky Mountains, where it fed on smaller vertebrates and probably harassed other shorebirds for food and feasted on dead fish (e.g. Knightia) during summer dieoffs due to oxygen depletion in the eutrophic lakes.
The original law was passed to satisfy the terms of an agreement with the United States, signed because of concern in both countries of uncontrolled hunting of waterfowl and shorebirds.
It is a natural habitat for shellfish, migrating and wintering waterfowl, colonial nesting waterbirds, beach-nesting birds, migratory shorebirds, raptors, and rare plants.
The bay is part of the South Arm Important Bird Area (IBA), identified as such by BirdLife International because of its importance for the conservation of Pied Oystercatchers and of the migratory waders, or shorebirds, of the East Asian – Australasian Flyway.
The various Summer Lake habitats supports a diverse population of upland game birds, songbirds, shorebirds, waterfowl, and birds of prey.
The coastal location also makes this refuge an excellent migration place for shorebirds, raptors and songbirds.