Jennifer L. Watts
Doctoral Candidate, University of California-Davis, Davis, California

"Evaluating the Impact of Fish Cage Waste on Marine Environments in Costa Rica"

(Category: Waste Minimization and Management)

Increasing population growth in the coastal region is creating over-exploitation of near-shore fisheries stocks. Scientists and fisheries biologists worldwide are concluding that fisheries yields have leveled off and that further increases in fisheries production will depend upon growth in the aquaculture sector. It is believed that marine fish cultivation has the potential to become a new income producing activity for local residents. The Costa Rican government and academic institutions are working to develop the methodology and expertise needed to cultivate spotted snapper, a native fish species, in floating cages. As this idea progresses, the development and management of such an industry must address the ability of coastal ecosystems to absorb the wastes that would be generated from the fish cages. Ms. Watts plans to develop the cage and net-pen systems for native marine fish as an alternative to capture fisheries. Using a new geochemical technique, she will trace the fate of nutrients in the environment near the fish cages. Ms. Watts is also evaluating the combination of fish cages and filter-feeding mollusks, and systems that would raise several different harvestable plants or animals together so that space and nutrients are used to the fullest extent possible to optimize the use of resources and recycle feed and wastes from the cages.