The following schedule is from the 72nd Annual Conference of the Southeastern Association of Fish & Wildlife Agencies which was held October 21-24, 2018 in Mobile, Alabama.
AUTHORS: J. Wesley Neal, Mississippi State University
ABSTRACT: Artificial destratification disrupts density differences associated with stratification, allowing homogenization of the water body in terms of temperature, oxygen, and other physicochemical characteristics. Lake and pond destratification as a management tool has been increasing in recent years, yet data are limited regarding its effects on fish communities. This case study examines the response of a largemouth bass (Micropterus salmoides) population to destratification over nearly a decade. Relative biomass (35.8-42.8 kg/ha) and abundance (51-93 fish/ha) of stock-sized (=200 mm TL) largemouth bass were both consistently low prior to installation of the system, but then relative biomass tripled (129.8 kg/ha) and relative abundance quadrupled (334 fish/ha) and remained high for the duration of the study. Concurrently, mean weight of fish and mean relative weight (Wr) declined continuously following population expansion, suggesting that population biomass had overshot carrying capacity. Although lack of replication precludes conclusive assignment of causation, the magnitude of change following years of relative stability suggests that continuous destratification may increase carrying capacity for largemouth bass in eutrophic southern ponds, and that more research on the effects of destratification in small impoundments is warranted. If destratification can double or triple standing biomass while greatly reducing the risks of oxygen-related fish kills, the cost of these systems could be more easily justified by managers of ponds and small lakes.
