COMPARISON OF DIFFERENT POND PRODUCTION SYSTEMS FOR RAISING LARGEMOUTH BASS

The largemouth bass (LMB), Micropterus salmoides is a  Centrarchid freshwater species native to North America and the most sought-after sport fish in the US. As demand for live and fresh fish increase LMB are emerging as a promising aquaculture business sector in the US. In fact, the 2013 US Census of Aquaculture indicated that 60 farms produced 976 tons of food-size LMB with an estimated value of $11.4 million.

Survival and growth of LMB produced in traditional levee ponds is quite variable.  This study will compare four different production systems for raising LMB for the food fish market in order to assess the possibility of increasing production with alternative rearing techniques.  Intensively aerated ponds and split pond systems have been demonstrated as a means to increase production in the catfish industry compared to traditional levee pond culture techniques; however, this production system has not been evaluated for LMB.  Likewise, the use of PondDtox® to eliminate hydrogen sulfide and improve water quality has been demonstrated as a positive benefit in the baitfish industry but as of yet is untested by commercial farmers raising LMB in ponds. Twelve 0.1 acre ponds were utilized for the production of LMB as follows: traditional ponds, traditional ponds with addition of detoxifying bacteria PondDtox®, high aeration (20 HP/acre), and split pond system. The first two production systems (traditional, traditional + PondDtox®) were stocked at 3,000 fish per acre, and the last two production systems (high aeration, split pond) at 5,000 fish per acre, using three replicates per treatment. The trial is currently ongoing and will be harvested after 150 days.

Feed-trained LMB fingerlings with an individual average weight of 128±47.6 g (CV=37.2%) were stocked on June 1 and 3, 2015. Fish were fed a formulated diet (48% protein and 18% lipid). Feed was offered four times a day, with a daily feed ration set at 3% of total body weight and re-adjusted to the initial body weight bi-weekly. Mortality was checked twice daily. Water temperature and dissolved oxygen were measured twice per day. Pond water was sampled weekly and analyzed for total ammonia nitrogen (TAN), nitrite nitrogen (NO₂^--N), and nitrate nitrogen (NO₃^-N).