Abstract:
Fecundity of yellow perch (Perca flaveacens Mitchill) was evaluated for fish from Lake Michigan near Michigan City, Indiana in 1985 and 1986. Pre-spawning gillnet-captured fish (n = 83) used for fecundity models ranged from 172 to 290 mm maximum total length and age 3 to 6. Fecundity estimations were completed using both volumetric and gravimetric methods.Comparison of estimated fecundities to total counts of eggs from three fish (202, 227, and 242 mm) revealed volumetric estimates more closely approximated the actual (mean error -3.4% SD 8.2%) than did gravimetric estimates (mean error +8.8% SD 6.5%). Equations describing fecundity (F) as a function of total length (L) were developed as least squares linear regression models. All models utilized means for fish in 10 mm intervals transformed to base 10 logarithms. The 1985 and 1986 data were combined by method of fecundity estimation since no difference in models was found between years (P >0.05). The 1985-86 model based on volumetric estimates was log F = -4.0396 + (3.5834) log L (r = 0.982) while the 1985-86 model based on gravimetric estimates was log F = -3.8258 + (3.5097) log L (r = 0.986). The volumetric model was used to predict fecundity based on length and age.The fecundity of yellow perch has previously been reported for fish collected from Lake Michigan near Ludington, Michigan in 1972 (Brazo et al. 1975), and Saugatuck, Michigan in 1972 and 1979 (Wells and Jorgenson 1983). The regression models relating log F as a function of log L in these studies fall within the 95' confidence interval of the 1985-86 volumetric model. This confirms that over the length range compared, fecundity as a function of length in the present study does not significantly differ from that reported previously for Lake Michigan yellow perch.