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Age Estimates and Length Distributions of Ontario Channel Darter (Percina copelandi) Populations

ABSTRACT The demographics of two Ontario channel darter (Percina copelandi) populations were investigated. A total of 347 channel darters was captured from riffle and shoal habitats along the Salmon River and the Trent River. The total length of most darters was between 50 and 65 mm. Based on otolith examination, the majority of darters was age 2 to age 3 (76%) in the Salmon River and age 3 (60%) in the Trent River. Growth was generally complete within the first two to three years. During June, spawning ready males and females were collected from shoal and rime habitats. The total length of these males and females in the Trent River was not significantly different and averaged 57 and 58 mm, respectively. Based on length-at-age data, first maturity was estimated to occur at age 2.