Shrimp Fisheries

Shrimp are a much desired and nutritious food product with a high economic value: capture-biomass ratio. The most important shrimp fisheries take place in marine habitats and are dominated by estuary-dependent “warm-water” species of penaeid and sergestid shrimps. Fishing with otter and beam trawls accounts for the major part of shrimp production, as these gears target species that form large schools over relatively level open ocean bottoms. Bycatch and discard of nontarget species are a particular problem of shrimp trawling, which disrupts bottom communities and removes juveniles of ecologically and commercially important finfish. The destructive effect of heavy trawls on the open soft-bottom habitats of most important species is not as severe as in other fisheries, given the rapid recovery of soft-bottom communities. Management of shrimp fisheries to prevent both growth and recruitment overfishing is based on models incorporating variables such as measures of growth, mortality, and climatic factors. Fishing efforts can be controlled by limiting access (e.g., number of fishers, vessels) and regulating seasonal closures of fishing grounds. Although there are signs of overfishing in some shrimp populations, the short life cycle (one to two years) with the rapid growth of major shrimp species makes them relatively resilient to overfishing. Conflicts between aquaculture and shrimp fisheries include economic competition and the biological impacts of shrimp aquaculture on natural shrimp populations. Protection and restoration of coastal wetlands, which serve as shrimp nurseries, are vital to the future of shrimp fisheries.