Assessment of Potential Indicator Species for Monitoring ...

ABSTRACT
Fifty seven species of amphibians, birds and mammals, were considered as
potential indicators of chemical contamination in the aquatic component of the Fraser
River Basin, British Columbia. A list of criterion were applied to rank the suitability of each
species. Criteria were based on published knowledge and the practicality of sample
collection. Criteria included: 1) fundamental attributes of residency, distribution,
abundance and diet; 2) current understanding and documentation of natural history, such
as home range, habitat, migration and historic abundance; 3) the ease of collection
samples; 4) the suitability of each species for laboratory study; and 5) knowledge
availability pertaining to contaminant research. The suitability of each species, expressed
as a score out of 19, was based on how well it fulfilled each selection criteria. The highest
score attained for mammals was 19 for the River Otter. For the birds, the highest scores
were 16 for the Great Blue Heron and 15 for the Osprey. The scores for amphibians were
notably lower than those of mammals and birds. The highest score attained was 12 for the
Rough-skinned Newt.
The results reflect differences in the availability of information and the extent to
which various species have been studied. Therefore, it is possible that low scoring
species may be upgraded when missing information is acquired. This project was the first
attempt at evaluating indicator species for the Fraser River Basin, and although higher
scores are significant, results are not exclusive and should serve as a guide only. When
designing a contaminant monitoring program and attempting to select the most
appropriate indicator species, consideration must be given to individual program
objectives, specific contaminant chemistry, and any relationships of the latter with a
particular species' ecology.
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