River contamination by paper mill effluents

The Pigeon River study.

Spatial (site) responses.

Relative (percent) difference in various bioindicators for redbreast sunfish sample and four Pigeon River sites compared to the mean of the two reference sites. Asterisks indicate a significant difference in response from the internal reference site (PRK 103).

Various measures of reproductive condition (number of vitellogenic, clutch, and atretic oocytes) in female redbreast sunfish collected at four Pigeon River sites, and two reference sites.

Distribution of fish sizes at reference and contaminated (Pigeon River) sites. At the upper two Pigeon River sites, a general lack of small fish indicates poor recruitment, which is probably due to reproductive impairment ( see previous figure).

Growth of sunfish at 3 Pigeon River and 3 reference sites demonstrating that growth of Pigeon River fish is much higher than reference fish. This may be due to low population abundance and reduced competition for food for Pigeon River Sunfish.

Extensive hyperpasia of secondary gill lamellae of redbreast sunfish collected from the Pigeon River below the paper mill. The gills are fused together at the ends of the lamellae (see below) preventing proper exchange of respiratory gases.

Integrated bioindicator responses at each of the contaminated sites (red) and the
reference sites (blue) based on 15-20 individual health response measurements at each site. Fish from the site nearest the mill discharge (PRK 89) had the poorest health, while fish from the lower Pigeon River site (PRK 27) had the best health. If the integrated site responses indicated by ellipsoids overlap, then health of fish at these sites are not significantly different

<< Home | Back | Spatial (site) Responses | Temporal (recovery) Responses >>