The Response of Fish and Fish Habitat to Logging in Previously Logged Catchments: Results from Multiple Paired-Watershed Studies

Forest practices in the Pacific Northwest have evolved considerably over the past century.  Increased recognition of the strong linkages between terrestrial and aquatic ecosystems has led to an evolving series of state and federal forest harvest regulations designed to protect aquatic resources.  Much of what is known on the effects of forest management on aquatic systems is from studies carried out during an era when naturally regenerated old-growth or late seral stage forests were converted to plantations.  Currently, forest harvest occurs primarily in stands that have been previously harvested.  Three separate studies, using a paired-catchment approach, were initiated in western Oregon to evaluate the effects of contemporary logging practices applied under the current state regulations on aquatic resources.  We use a Before-After-Control-Impact design in combination with an individual fish based modeling approach.  This allowed us to assess the acute response of headwater fish communities to logging and to extend the scope of inference over larger time intervals.