Effects of a marsh management plan on fishery communities in Coastal Louisiana

Abstract

The effectiveness of a marsh management plan, involving a seasonal drawdown of brackish and freshwater marshes, on fishery communities and salinity were examined. The plan goals of reducing salinities and increasing circulation were not achieved during the drawdown, but salinities were buffered, and circulation improved during the nondrawdown phase. Significantly more grass shrimp (Palaemonetes sp.), least killifish (Heterandria formosa), western mosquitofish (Gambusia affinis), and golden topminnow (Fundulus chrysotus) were collected in the managed area. More marine-transient organisms, primarily gulf menhaden (Brevoortia patronus), blue crab (Callinectes sapidus), and striped mullet (Mugil cephalus) were collected in the unmanaged area. Salinities were significantly higher in the managed area during the drawdown but not during the nondrawdown period. Water levels in the managed area were less variable.