Summary
More than 80 fish species are found in the freshwater and brackish waters of the St. Lawrence River and evaluation of the status of these fish stocks is complex. In order to paint a current picture of our understanding of the fish communities and aquatic habitats of the St. Lawrence, and to judge the evolution of these elements over the last 25 years, different status indicators were used: (1) Index of Biotic Integrity, (2) status of the stock of certain species subject to recreational and commercial fishing, (3) status of species under threat, (4) coastal zone fish biodiversity index and (5) relative abundance index for submerged aquatic vegetation. Analysis of these indicators highlights what are sometimes very different findings between species and sectors. Several rapid changes that have arisen during the last two decades in the characteristics of aquatic habitats and in the structure of fish communities testify to an evolving ecosystem that is tending to degrade in certain sectors. Over the years, several exploited fish stocks have seen periods of decline. While certain species have been able to re-establish themselves thanks to restrictive management measures, others have been slow to recover due to several factors other than pressures from fishing.
File
Sector(s):
Wildlife
Theme(s):
Wildlife
Author(s)
Direction de l'expertise sur la faune aquatique
Year of publication :
2020
Format :
Keywords :
St. Lawrence river; fish communities of the freshwater; fish communities of Québec; indicator; health status; St. Lawrence Action Plan
This publication exists in other language: État des communautés de poissons des eaux douces et saumâtres du Saint-Laurent
