Reference Commencement Elliott 
areas Bay Bay 
Figure 5. Numbers of species that colonized 20.3 cm x 20.3 cm horizontal 
substrates over 6-month periods at seven sites in Puget Sound. 
Summary 
The concentrations of toxic chemicals are clearly most elevated in the 
sediments of parts of the industrial harbors and waterways near urban 
centers of the region. Measures of biological stress usually indicate the 
biota are most affected in these same areas. There are many signs of 
subtle sublethal effects, e.g., the liver lesions in flatfish, and the 
enlarged livers among gulls. 
43 
