As the world increasingly turns to aqua farming to feed its growing population, there's no better time than now to design an aquaculture system that is sustainable and efficient.
Researchers at UC Santa Barbara, the University of Tasmania and the International Atomic Agency examined the current practice of catching wild fish for forage (to feed farmed fish) and concluded that using novel, non-fishmeal feeds could help boost production while treading lightly on marine ecosystems and reserving more of these small, nutritious fish for human consumption.
"The annual catch of wild fish has been static for almost 40 years, but over the same period the production from aquaculture has grown enormously," said Richard Cottrell, lead author of a paper that appears in the journal Nature Food.
Approximately 16 million of the 29 million tons of forage fish -- such as herrings, sardines and anchovies -- caught each year globally are currently used for aquaculture feed. To meet the growing demand for fish in a sustainable manner, other types of fish feed must be used, the researchers said.
"We looked at a range of scenarios to predict future aquaculture production and, depending on consumer preferences, we found growth between 37-98% is likely," said Cottrell, a postdoctoral scholar at UCSB's National Center for Ecological Analysis & Synthesis (NCEAS), who conducted this work at the University of Tasmania.
Fortunately, nutritional sources exist that could ease the growing demand for forage fish. Based on microalgae, insect protein and oils, these novel feeds could, in many cases, at least partially substitute fishmeal and oil in the feeds of many species without negative impacts on feed efficiency or omega-3 profiles.
As we lean more on ocean-based food, the practices in place for producing it must come under scrutiny, and be improved where possible, according to UCB marine ecologist and co-author Ben Halpern, director of NCEAS. This study is one of several examinations of the potential for novel feed ingredients to replace wild-caught forage fish in aquaculture. Research in this study was also conducted by Halley E. Froehlich at UCSB and Marc Metian at the International Atomic Agency in Monaco.
(Source: Agriculture and Food News, ScienceDaily. www.sciencedaily.com)