South Slough Estuary

South Slough Estuary

  • Moderate
  • 3.4-mile loop
  • 300 feet elevation loss


The city of Coos Bay was once called Marshfield, but the name no longer fits. Ninety percent of the bay’s original marsh fields have been destroyed—diked, drained, or filled for development. Now wildlife biologists are understanding the importance of these lost tidal wetlands. When freshwater salmon smolts migrate to sea, for example, they need to linger in estuaries to gradually adjust to saltwater. Clams, herons, raccoons, and hundreds of other species rely on the rich life of the mudflats once derided as worthless sloughs.


The nation’s first Estuarine Research Reserve was established here in 1974 on 7 square miles of abandoned farmland and cut-over forest bordering Coos Bay’s South Slough. Displays in a modern interpretive center explain how breached dikes and regrowing forests are allowing wildlife to flourish, but a network of easy trails nearby allows you to investigate the reserve first hand.

From Highway 101 …


This chapter taken from the book 100 Hikes/Travel Guide: Oregon Coast & Coast Range.