Effects of a Pulp Mill Effluent on the Population Dynamics of Perch, Perca fluviatilis

Publisher Website
Google Scholar
Abstract
The dynamics of a Baltic perch (Perca fluviatilis) population were studied in a bleached pulp mill effluent area on the Swedish coast. Recruitment was seriously affected, as larval and fry abundances were very low. Studies of spawning on artificial substrates demonstrated that sufficient numbers of eggs were deposited even in the most effluent-exposed parts of the study area. No increased egg mortality could be noted, but at the stage close to hatching about 10% of the embryos were observed to be malformed, generally having sharp bends in the posterior part of the spinal cord. Exposed embryos were generally smaller than reference fishes, both when length and weight data were compared. Larval samplings provided evidence for high mortality at or very close to hatching. Food and feeding conditions appeared to be of little importance for mortality. Two mortality causes were suggested: chronic failure of parental reproductive systems and/or acute toxicity to embryo or early larvae.

This publication has 1 reference indexed in Scilit: