Fish farmers will need to double production of finfish and shellfish by 2050 to meet projected demand for fish, says a report by the World Resources Institute. Aquaculture now provides almost half of the fish consumed by people. The seas and inland waters are fished to their limits already, said WRI, so larger aquaculture output is needed. The report suggests five approaches to minimize the enironmental impact of a larger fish industry. They include research into breeding, feed and disease control to make the industry more efficient and shifting consumption toward fish such as catfish and tilapia that require less time and attention.