The Site is one of the largest estuaries in Finland, formed by the River Kyrönjoki, an exceptionally wide reed zone, and a large area of open water which remains shallow because of silt brought by the river. The wetland is for the most part surrounded by forests and on the northwestern and southern sides by farmland. It is an important breeding and staging area for waterfowl and waders during their migration and moulting periods. The vulnerable lesser white-fronted goose (Anser erythropus) and the common pochard (Aythya ferina) visit during their migrations. The estuary is an important fish spawning area, despite the inflow of sediments, nutrients and occasional acid river waters. Dredging of boating channels, the building of embankments and acid waters leaking from the embankments have destroyed vegetation in many places, and the wetland area has diminished by hundreds of hectares. Its former significance as a spawning area has reduced as fish and benthic species have disappeared in certain areas. The eastern shores are densely built and a main road crosses the southern edge of the Bay. Nonetheless, birdwatching remains popular. A Site management plan was being prepared in 2023, while a restoration plan has been implemented to prevent overgrowing of open grasslands.