Growth, Survival, and Vulnerability to Angling of Three Wild Brook Trout Strains Exposed to Different Levels of Angler Exploitation

Abstract

Abstract It has been suggested that the genetic growth potential of trout may be degraded over time by differential angler harvest of the faster-growing fish of each cohort. To test this hypothesis, young-of-the-year wild brook trout Salvelinus fontinalis from two branches of the Au Sable River and from the East Branch of the Fox River were stocked in three experimental Michigan lakes to determine their relative 2-year growth and survival. Brook trout populations from the Au Sable River are believed to have been exploited more intensively than the population from the East Branch of the Fox River. We found that brook trout from the East Branch Fox River grew significantly faster than fish from either the North Branch or the mainstream Au Sable River. The superior growth of East Branch Fox River brook trout was most evident in Hemlock Lake, where all strains grew best. Mature males were significantly longer and heavier than mature females when data were pooled across strains for each lake, East Branch Fox R...