Urban stormwater runoff often contains an extraordinarily complex mixture of chemicals that may number in the thousands of distinct compounds. Many of these chemicals remain unidentified, with as-yet unknown environmental effects.
Nevertheless, recent research by NOAA, the U.S. Fish and Wildlife Service, and academic research groups at Washington State University and the University of Washington have shown that untreated stormwater can be highly toxic to Pacific salmon as well as their macroinvertebrate prey.
Moreover, pollutant removal strategies using green infrastructure approaches such as bioinfiltration can effectively reverse these biological impacts. For coho salmon (Oncorhynchus kisutch) in particular, extensive landscape modeling has shown that acute spawner mortality can be predicted from certain aspects of urban land use (e.g., motor vehicle traffic density).
This presentation will explore how the chemical composition of urban stormwater changes across gradients of urbanization, in relation to both traditional measures of stream macroinvertebrate richness as well as the survival and reproductive success of highly migratory salmon.