Information actualisée sur les populations de saumon atlantique (Salmo salar) de l'est du Cap-Breton (ECB; zone de pêche du saumon 19) pertinente pour l'élaboration d'un 2e rapport de situation du COSEPAC

Abstract

The purpose of this research document is to summarize and update the present status and recent trends of Atlantic Salmon populations in the Eastern Cape Breton (ECB) Designatable Unit (DU) of relevance to the development of the status report by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC). There are 46 watersheds known to contain or have contained Atlantic Salmon in the DU, and additional smaller streams have been identified as likely to contain or historically contained Atlantic Salmon. Atlantic Salmon population monitoring in ECB has focused on five river systems: Middle, Baddeck, North, Grand, and Clyburn. Assessments on these rivers have been based on fishery independent counts by dive surveys or at a fish ladder and/or recreational catch reports. Of these five populations, two (Grand and Clyburn) show marked declines in adult abundance over the last 3-generations of available data. Two populations (Middle and Baddeck) have remained relatively stable at abundances below their conservation requirements and one population (North) is estimated to be near or above its conservation requirement in recent years. Recreational catch data for other rivers in the ECB DU suggests that Atlantic Salmon abundance is low throughout most of the DU. Intermittent electrofishing surveys also indicate that juvenile densities are below reference values at many locations throughout the ECB DU, although juvenile salmon are still widely distributed. A number of threats to Atlantic Salmon are identified in the freshwater and estuarine/marine environment of the ECB DU, including illegal fishing/poaching, salmonid aquaculture, marine ecosystem change, disease and parasites, and many others.