In a three year study, the applicability of the cortisol response to capture as a biomarker of the health of fish from areas chronically exposed to pollution was assessed. Northern pike (Esox lucius) and yellow perch (Perca flavescens) captured from an area contaminated by bleached kraft pulp mill effluent (BKME) were initially found to be incapable of elevating their blood cortisol concentration to reference levels. Following a reduction of the amount of absorbable organochlorines (AOX) in the BKME, fish downstream of the mill regained their normal cortisol response to capture. The time frame for this recovery was from between 6 to 18 months. Fewer young fish downstream of the effluent provided evidence for the impact of long-term exposure to BKME at the population level. / The impairment of the cortisol response to capture, and its subsequent recovery after effluent reduction provide the foundation for developing cortisol as a biomarker of contaminant exposure. Further work should determine the relationship between cortisol and the effect at higher levels of biological organization (e.g., population and community).
Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.68170 |
Date | January 1993 |
Creators | Downing, Gavin |
Contributors | Rasmussen, J. B. (advisor) |
Publisher | McGill University |
Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
Language | English |
Detected Language | English |
Type | Electronic Thesis or Dissertation |
Format | application/pdf |
Coverage | Master of Science (Department of Biology.) |
Rights | All items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated. |
Relation | alephsysno: 001396213, proquestno: AAIMM94428, Theses scanned by UMI/ProQuest. |
Page generated in 0.0024 seconds