SEASONAL GROWTH OF NORTHERN PIKE (ESOX-LUCIUS) IN A SOUTH-DAKOTA GLACIAL LAKE

The growth of northern pike (Esox lucius) in Lake Thompson, South Dako ta was assessed seasonally over a two-year period. Northern pike were short-lived; the oldest fish collected was age 8. Female northern pike lived longer than male fish, and mean length-at-age was significantly higher for females than for males. Significant increases in mean body length occurred during cool- and cold-water seasons, but no increases in mean length were found for either sex from July through August, wh ich was the period of highest water temperature. Incremental growth in length (mm/d) for male northern pike was related to water temperature , with maximum growth rates occurring in the range of approximately 8- 18 degrees C.