Carbaryl, Carbofuran, and Methomyl - National Marine Fisheries ...

contaminants and scours stream bottoms with high flows. Consequently, urban environments do
not typically support diverse communities of aquatic invertebrates (Paul and Meyer 2001;
Morley and Karr 2002).
Similarly, yet due to a different set of circumstances, watersheds with intensive agriculture land
uses show compromised invertebrate communities (Cuffney, Meador et al. 1997). Indices of
biological integrity (IBI) and other invertebrate community metrics are useful measures of the
health of an aquatic community because cumulative impacts of aquatic stressors are integrated
over time. The IBI is also valuable because it converts relative abundance data of a species
assemblage into a single index of biological integrity (Allan 1995). Salmonid-inhabited
watersheds have been assessed using IBIs and other metrics of aquatic community health.
A study on the condition of Yakima River Basin’s aquatic benthic community found that
invertebrate taxa richness was directly related to the intensity of agriculture i.e., at higher
agriculture intensities taxa richness declined significantly both for invertebrates as well as for
fish (Cuffney, Meador et al. 1997). Locations with high levels of impairment were associated
with high levels of pesticides and other agricultural activities, which together with habitat
degradation were likely responsible for poor aquatic conditions in the Yakima (Cuffney, Meador
et al. 1997). Salmonid ESUs and DPSs occur in the Yakima River Basin as well as other
watersheds where invertebrate community measurements indicate severely compromised aquatic
invertebrate communities such as the Willamette River Basin, Puget Sound Basin, and the
Sacramento-San Joaquin River Basin.
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