Lastly, comparison of PCB striped bass model simulation results and 1987-97 field data (TAMS/ Gradient, 1995) are shown for 2-5-year-old striped bass in the mid estuary (Fig. 25.8). Simulated results are denoted by disconnected lines to represent only the portion of the year that striped bass are in the mid estuary. Field data are presented as seasonal (three-month) average concentrations with 5 and 95 percentiles. For fall 1990 and fall 1992, average concentrations were recalculated after eliminating a few high outliers from the sample distributions (Farley et al., 1999). As shown in Figure 25.8, model results are consistent with average observed concentrations in striped bass, and show a slight increase from fall to spring as the young fish overwinter in the mid estuary. A slow decline in PCB concentrations in 2-5-year-old striped bass is also determined with average concentrations of approximately 1 |g g-1(wet weight) at the end of the simulation period in 2002. Similar responses are obtained for PCB accumulations in older striped bass (not shown) with average concentrations of approximately 2 |gg-1 (wet weight).

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