Genetically-marked strains of walleye (Stizostedion vitreum vitreuni) from Arkansas (ARS) and Iowa (IAS) were stocked simultaneously into a Texas reservoir in 1985 to evaluate strain-related performance differences associated with spawning and growth. Post-stocking collections made during the spring spawning season (1988-1990) resulted in the capture of 132 walleyes from this year class. ARS walleyes comprised 35% of 1985 year-class samples which was significantly higher than the stocking proportion (26%). Differences were attributed to ARS females being more abundant than IAS females in samples. This unexpectedly high abundance of ARS walleye was not considered an indication of higher survival but merely evidence of temporal differences in movement of females of each strain to spawning grounds. This hypothesis was supported by strain-related sex ratio differences identified in samples; ARS ratios favored females whereas IAS ratios favored males. Survival was deemed similar between strains throughout the duration of the 5-year study. Natural year classes were produced following the introductions, but they could not be specifically traced to ARS walleye spawning. ARS walleyes attained larger sizes than IAS walleyes. ARS females were significantly longer and heavier than IAS females by age 3. ARS males were significantly longer and heavier than IAS males by age 4. Future stockings of ARS walleyes in Texas may provide anglers with larger walleyes than have typically been available with IAS walleye but they do not hold promise for increasing natural reproduction.
Fisheries Outstanding Technical Paper