The goals of this proposed work are to: 1) develop and test methods for monitoring headwater stream conditions at the subcatchment and stream levels, 2) determine the effects of land-use (timber harvest and roading) and vegetation cover (which is under geoclimatic control) on the biological productivity of subcatchments, and 3) use this information to relate watershed condition of fishless subcatchments to fish communities in downstream habitats. The headwaters monitoring focuses on food web productivity (i.e., the amount of aquatic arthropod biomass and organic detritus produced and exported to fish habitats) as an integrator of the processes and environmental constraints driving these ecosystems.  It is also meant to determine whether food web productivity is a key determinant of the population ecology, foraging behavior and sustainability of downstream fish assemblages which include sensitive anadromous species and resident species.

Role of Wenatchee Aquatic and Land Interactions (WALI) Team:

Overview:  WALI is in a contractual agreement with Bonneville Power Administration (BPA) and is working cooperatively with scientists from the University of Alaska at Fairbanks (contract #24727).  BPA initiated the research program "Integrated Status and Effectiveness Monitoring" in 2003 to assess the health of aquatic resources and fisheries in the Wenatchee sub-basin of the Upper Columbia River Watershed.  Productivity derived from headwater streams could be a critical component of ecosystem health in the Wenatchee sub-basin and the WALI Team is equipped with the expertise to conduct such a detailed analysis.  The nature of the agreement between BPA and WALI is also cooperative in the sense that some research activities are directly funded by BPA and some are provided by WALI in-kind.

Dr. Karl Polivka is a Co-Principal Investigator on the project and is leading the fish ecology portions of the study.  These include: (1) Studies of productivity in fish-bearing habitat. Because the macroinvertebrate community downstream of headwater junctions may show the effects of input from the headwaters, Polivka is leading the WALI team's study of benthic invertebrates in fish-bearing streams. (2) An assessment of baseline productivity informs other aspects of the study such as fish responses (including diet) resulting from prey delivery from the headwater tributaries. We are linking the relative contribution of invertebrate based food webs found in the headwater streams and that of the fish-bearing streams to the condition of relevant fish populations using direct measures of fish diet, condition and behavior to establish how strongly connected the energetic inputs of headwater streams are to the persistence of resident and anadromous species.  Dr. Polivka's contribution to the project is provided in-kind to the amount of 0.25 FTE.