The White River Marsh IBA includes White River Marsh State Wildlife Area and Puchyan Prairie and Snake Creek Fen State Natural Areas. The site presents a complex of high-quality natural communities including the most extensive sedge meadows in southern Wisconsin as well as wet prairie, open bog, and flowages. Prairie pasture, planted grasslands, some croplands, oak barrens, savanna, and woodland are found in the uplands.
The extensive wetlands are this site’s most significant feature, hosting rare species like Le Conte’s sparrow and yellow rail (at its southernmost location in Wisconsin), as well as American bittern, Northern harrier, sedge wren, Henslow’s sparrow, swamp sparrow, and bobolink. Savanna and woodland habitats provide for red-headed woodpecker, field sparrow, Acadian flycatcher, wood thrush, and cerulean warbler. The site also is a significant concentration area for migrating waterfowl and waterbirds in both spring and fall, and is used by thousands of staging sandhill cranes in the fall.