Bottom depth for the 257 stations sampled in waters of the West Coast 
shelf ranged from 28 m to 138 m. Four stations, all from the SCB sampled as 
part of the Bight ’03 study, exceeded the target frame depth of 120 m but were 
included in the analyses in order to obtain adequate sample numbers from some 
multi-density categories. The mean depth of the waters of the West Coast shelf 
sampled was 72.6 m (Figure 3.1.10). 
A variety of bottom types was encountered among the various stations. 
Along the Pacific coastline of Washington, the seabed was mostly fine sand, with 
' a higher incidence of silt and clay in water depths greater than 60 m. Five 
stations in Washington could not be sampled due to the presence of hard bottom 
and thus were replaced with alternate sites from the sampling design. Three 
stations in the Strait of Juan de Fuca could not be sampled because they fell in 
an area of seabed composed of coarse gravel, cobbles and rock fragments. 
These stations were replaced with reserve sites along the Pacific coastline, 
outside the Strait of Juan de Fuca, and near the mouth of the Columbia River. 
Along the Oregon coastline, fine sand was also the most common bottom type 
encountered. The sediment collected during the California leg of the cruise was 
highly variable and included both fine sands and silty sediments. The highest 
percentages of fine sediments were found at California stations. Two stations 
along the California coastline had to be abandoned due to rocky conditions and 
were replaced with alternate stations. Further details on sediment composition 
are presented in Section 3.3.1 below. 
28 
