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Pond Substrate Type Affects Yellow Perch Fingerling Size at Harvest

Fish size and harvest density generally exhibit a 
negative relationship in pond culture, but the influence that pond substrate 
type can have on this relationship is not well understood. To evaluate the 
influence of pond substrate type on yellow perch (Perca flavescens), harvest density 
(number/hectare) was linearly regressed against individual fingerling size 
(grams) for lined (n = 48) and earthen (n = 40) substrate ponds that were 
treated similarly in terms of organic fertilizer use and the number of days in 
the pond over 12 culture seasons at Blue Dog Lake State Hatchery, South Dakota, 
USA. Harvest density explained 45 and 39% of the variation in yellow perch size 
in lined and earthen-substrate ponds (all P P = 0.62); however, 
fingerling size was significantly larger in lined ponds regardless of density 
that varied from near 0 to 700,000 per hectare (y-intercept comparison, P < 0.01). At the same 
harvest density, lined ponds will tend to produce larger yellow perch 
fingerlings compared to earthen ponds when similar organic fertilizers are 
used.