Pond production of pellet-fed advanced juvenile and food-size largemouth bass

Abstract

Pond production of 100–200 g advanced juveniles and 400–450 g food-size largemouth bass (LMB) was evaluated. Ten 0.04-ha ponds stocked with different densities and at different times with 4.3–11.6 g young-of-the-year LMB were used to evaluate the production of advanced juveniles. Fish were trained prior to stocking to feed on 40% protein floating trout pellets to satiation, twice a day. Ponds had no water exchange except to compensate for evaporation and seepage losses and were provided with emergency aeration. Regression analysis showed that gross yield increased from 2995 to 6008 kg ha −1, fish growth decreased from 1.47 to 0.86 g day −1 and mean harvest weight decreased from 204 to 88 g as stocking rates increased from 17 000 to 67 136 fish ha −1. Feed conversion ratio for advanced juveniles averaged 1.07 and was not affected by stocking rates. Average fish survival was 82%. In a second trial, twelve 0.04-ha ponds were stocked with 62-g, 1-year-old LMB at 2470 and 7410 fish ha −1. Feeding and aeration were managed as described in the previous trial. Gross yields were 738 and 1742 kg ha −1 for the low and high stocking rates, respectively ( P < 0.01). Survival rates and feed conversion ratios were comparable ( P > 0.10) at both stocking rates (81% vs. 76% and 1.42 vs. 1.56, respectively). Fish growth and mean harvest weight were 1.47 g day −1 and 370 g at the low density and 1.16 g day −1 and 307 g at the high density rate, respectively. Young-of-the-year LMB seemed to feed more actively on pellets than did 1-year-old fish, which may be attributed to differences in fish size and age, differential effects of high water temperatures on feeding response of young-of-the-year and 1-year-old bass, and influence of alternative natural foods and overwintering on the retainment of pellet feeding behavior.