When Hal Mooney first approached me in the late 1990s to work with him on aquaculture, the industry was just beginning to flourish. Between 1987 and 1997, global aquaculture production more than doubled in volume and value, as did its contribution to world fish supplies. By 2000, aquaculture accounted for one-quarter of fish consumed directly by humans, and over 220 species of fish and shellfish were cultured. Aquaculture was viewed by many as a solution to overfishing wild fish stocks, but as Hal was quick to recognize, it could also be a threat to marine ecosystems if managed poorly. As was the case with many global ecological changes that Hal studied during the course of his career, he convened a small group of experts on the topic, with the goal of identifying the most critical issues that warranted immediate scientific attention. The process of scientific synthesis formed the core of our collaborative work and opened new areas of research. Convening experts in aquaculture science, fish nutrition, invasive species, freshwater and marine ecology, economics, and law guided the direction of scientific inquiry, and also influenced the direction of the aquaculture industry as it responded to the call for more sustainable practices.
Hal has always had a good eye for emerging issues in ecology. Aquaculture has now become the fastest growing sector in the world food economy and accounts for one-half of fish consumed directly by humans. Over 660 species of fish and shellfish are farmed in diverse systems around the world. The burgeoning field of aquaculture and ecological systems has led to new scientific insights on food web dynamics, pathogen transfers, animal nutrition, nutrient cycling, marine chemistry, and life cycle analysis. Although ecological damages from aquaculture abound, the rising volume of farmed fish has been achieved without commensurate increases in fishmeal and fish oil production, reflecting improved efficiencies in the sector over time. Ecologists and other scientists in the field are mixed in their optimism and pessimism, however, and research continues to probe sustainable solutions to fish-based feeds, pathogens, ocean acidification, waste disposal, and invasive species. As the world’s population and per capita consumption of fish continue to rise, aquaculture will play an even larger role in the future. Hal’s fundamental contribution to ecological research in the aquaculture field will pay off in spades.