Hubbs-SeaWorld Research Institute is partnering with the USDA, University of Idaho and Universidad Autónoma de Baja California to develop fish feeds with little or no fish protein and fish oil. In the project’s first two years, scientists showed the feasibility of rearing white seabass and California yellowtail on a diet in which the fishmeal was replaced with a combination of poultry by-products, corn protein and Spirulina. Neither fish growth nor feed conversion rates were compromised. Fish oil could be reduced by 75% in the fishmeal-free seabass feed with a mix of 50% poultry oil and 25% of either soy, corn or flax oil. For yellowtail, 87% of the fish oil could be replaced with poultry oil. Currently, scientists are studying the phosphorous requirements of seabass and yellowtail on fishmeal-free diets. The long-term challenge, to be revisited in this project or a subsequent one, will be to maintain the desirable omega-3 fatty acid content of farmed fish, without using fish oil.