Proceedings - Teaching and Learning Centre - Simon Fraser ...

Fraser River Action Plan 3rd Research Workshop
Summary
Resident Fish Condition and Contaminants Assessment
B.A. Raymond and D.P. Shaw
Environment Canada
The Fraser River Action Plan is assessing the condition of resident fish in the Fraser basin, based on health and
contaminant levels of mountain whitefish and peamouth chub. The health of resident fish populations is
important as an indicator of ecosystem health, and as a factor that can affect human health. Resident fish spend
their entire lifespan in the river and reflect more local conditions than migrants such as salmon.
Mountain whitefish were selected for this study because previous studies indicated that they accumulate
contaminants to higher levels than other species sampled, and research is being conducted on their life history in
the upper Fraser River. Peamouth chub are widely distributed and abundant in the Fraser River, are the target of
fish condition research in the upper Fraser River, and have been used in the Environmental Effects Monitoring
Program for pulp and paper mills on the Fraser River.
Mountain whitefish and peamouth chub were collected by beach seining between July and November, 1994,
from eleven reaches (Figure 1). All fish were examined in the field for external and internal abnormalities and
tissue samples were collected for histological assessment. The health assessment index (HAI) of Goede and
Barton (1990) 1 was incorporated because it is being widely applied in environmental studies. This study was an
opportunity to link the HAI to other variables, such as contaminant levels and histology.
Preliminary results for the HAI indicated that:
• A high incidence of HAI abnormalities occurred in peamouth chub and mountain whitefish;
• HAIs were significantly different among reaches;
• HAIs were not correlated with histological abnormalities (i.e., HAI abnormalities may not be signs of
“disease”);
• HAIs appeared to be unaffected by age (fish ages were significantly different among reaches);
• HAI was highest in the Nechako where contaminant and MFO levels were low; and,
• Factors other than contaminant exposure appeared to account for variability in the HAI.
HAI information gaps included:
• Cause-effect studies to determine causes of variability in the HAI and allowed application of this
technique to environmental management;
• Assessment of user variability (planned for 1996-7); and,
• Assessment of histological data quality (underway).
Analyses for contaminant exposure included MFO activity in liver; trace metals, PCBs, organochlorine
pesticides, chlorophenolics, dioxins and furans in muscle and liver; and PAH metabolites, chlorophenolics and
resin acids in bile.
Preliminary results for the contaminants indicated that:
• Contaminant levels in fish varied among reaches and species;
• Contaminant levels were generally low, near or below detection limits and guidelines (where guidelines
exist);
• TCDD and TCDF levels were highest in the Thompson system;
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