lesson was that most plant species only occurred in a limited number of sites, making it 
difficult to develop generally applicable metrics based on indicator species. While the 
present effort was not sufficient to develop wetland indicators by itself, it did feed into 
the development of the California Rapid Assessment Method (CRAM; 
http://www.cramwetlands.org/ ) and to similar rapid assessment surveys being 
conducted by U.S. EPA in Oregon. 
3.6 Summary 
Condition of the soft sediment habitat within the intertidal zone of the states of 
Washington, Oregon and California, with the exception of the estuarine portion of the 
Columbia River, was successfully assessed at 217 sites during the summer of 2002. 
The dominant types of estuarine intertidal habitat varied among the three states, 
although unvegetated sand or mud flats were the dominant habitat types for all three 
states. Shellfish beds (oysters), gravel bottom, and intertidal seagrasses were recorded 
only in Washington and Oregon. San Francisco Bay and the rest of California tended to 
have finer sediments, higher Total Organic Carbon, higher concentrations of sediment 
nitrogen and phosphorus, and higher average Effects Range-Median Quotient (ERM-Q) 
values than estuarine intertidal areas in Washington and Oregon. Levels of sediment 
contamination West wide were low, with only 0.21% of the intertidal area of the West 
Coast estuaries having exceedances of >5 Effects Range Low (ERL) concentrations 
and 0.3% of the intertidal area exceeding Effects Range Median (ERM) concentrations. 
Average densities of benthic infauna were highest in Oregon, with California and 
San Francisco having lower but similar abundances, and Washington having the lowest 
value. The benthic community was dominated by polychaetes, oligochaetes and 
amphipods. Surprisingly, the single most abundant polychaete in the West Coast 
intertidal was the nonindigenous Manayunkia aestuarina, introduced from the Northeast 
Atlantic. San Francisco habitats other than the high marsh were the most invaded with 
an average of almost 50% of the classified species per sample consisting of 
nonindigenous species. Puget Sound samples contained about 26% nonindigenous 
species compared to 40% to 44% for coastal Oregon and Washington. 
Vegetation was present in the quadrats at 150 of the 217 sites sampled, and 
included 28 emergent macrophytes, 2 seagrasses, and macroalgal taxa. Eighty-two 
percent of macrophyte taxa occurred at three or fewer sites. The most frequently 
occurring emergent macrophyte taxa were marsh jaumea ( Jaumea carnosa) and 
pickleweed ( Salicornia virginica). The greatest numbesr of emergent macrophyte 
species were observed in California (n = 11), and in San Francisco Bay (n = 17) where 
high marsh was included in the study. Mean relative cover of nonindigenous emergent 
macrophyte species was low (8%) throughout the West. Mean cover by nonindigenous 
species was highest in Washington (21%), where both salt marsh cordgrass Spartina 
alterniflora and the introduced seagrass Zostera japonica were found. No 
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