Distribution and Abundance of Salmonids in Prince Edward Island Streams

Abstract

The freshwater sports fishery of Prince Edward Island (PEI) revolves largely around three salmonid species—Salvelinus fontinalis (Brook Trout), Salmo salar (Atlantic Salmon), and the nonnative Oncorhynchus mykiss (Rainbow Trout). However, little is known about their current distribution and relative abundance on the Island. Of particular concern is the status of Atlantic Salmon, whose populations have declined dramatically in other parts of the Maritimes and are listed as “may be at risk” on PEI. We systematically sampled 69 streams with suitable juvenile salmonid habitat (riffle with gravel/cobble substrate), to provide baseline data concerning the population status of these three species. Brook Trout were found in all 69 streams, with a median density of 78.3 fish per 100 m2. Atlantic Salmon were found in 23 sites, at a median density of 11.6 fish per 100 m2. Rainbow Trout were found in only 19 streams, but at slightly higher densities of 16.2 fish per 100 m2. Present day distribution and abundance of all three species on the Island have been influenced by habitat modification and degradation.