In a new study, University of Michigan-led researchers find that strategic planning in mariculture could both enhance seafood production and protect marine biodiversity, offering a promising outlook for sustainable ocean farming.
An international team of researchers led by the University of Michigan has unveiled a study suggesting that humanity can significantly increase seafood production through mariculture while minimizing its environmental impact. The key lies in strategic planning, which could help balance the growing global demand for seafood with the need to protect marine biodiversity.
“We can achieve this sustainable mariculture development,” first author Deqiang Ma, who led the study as a postdoctoral researcher at U-M’s School for Environment and Sustainability, said in a news release. “With strategic planning, we can achieve the goal of conserving marine species while meeting the global demand for the expansion of mariculture.”
Mariculture, a branch of aquaculture focusing on saltwater seafood farming, plays a crucial role in feeding the global population, representing about 20% of the food from fisheries as of 2020.
As the demand for seafood rises, mariculture is expanding at a rapid pace. Ma and his team developed a model to estimate the impact of this growth on over 20,000 marine species.
Their model established a baseline for mariculture’s current impacts and projected changes through 2050 under various scenarios, including different species and geographical locations for farm development. The model also considered climate change scenarios RCP 4.5 and RCP 8.5, representing different levels of global warming and greenhouse gas emissions.
The best-case scenario offers encouraging results: by developing mariculture in areas with the least environmental impact, bivalve (shellfish) production could increase by 2.36 times and finfish by 1.82 times compared to current levels. This approach would reduce the global impact on marine biodiversity by as much as 30.5%.
Conversely, the worst-case scenario — developing mariculture in areas with high biodiversity sensitivity — could result in impacts more than four times worse than building farms at random locations.
This stark contrast highlights the importance of strategic planning, according to senior author Neil Carter, an associate professor at U-M’s School for Environment and Sustainability.
“It is critically important to leverage the growing insights across disciplines, whether it’s climate change science or economics or marine production,” Carter said in the news release. “All these different facets had to come together from other sources in order to make these forecasts.”
The study was a collaborative effort, including experts from the University of Washington, University of Freiburg in Germany, Hokkaido University in Japan and the University of California, Santa Barbara.
Benjamin Halpern, a professor at UCSB and director of the National Center for Ecological Analysis and Synthesis, emphasized the value of such cross-disciplinary work.
“But I’ve done this kind of work a lot in my career, and the payoffs can be enormous,” Halpern added. “The cross-disciplinary nature of the questions that can be addressed and the ability to look at them for every patch of ocean in the world makes the research much more relevant and impactful to society and the scientific community.”
This research points to the complexities and potential hurdles in achieving a sustainable future for mariculture. Different regions present unique opportunities and challenges, requiring tailored solutions. Additionally, even the best-case scenarios indicated some negative impacts on the marine ecosystem, particularly on iconic species like whales, seals, and sea lions.
“With these insights, we can see that it’s not a foregone conclusion that the expansion of an industry is always going to have a proportionally negative impact on the environment,” Carter added. “So the next part of this is getting policymakers and communities to interact with each other to figure out how we can actually implement some of these ideas to reduce those impacts and to prioritize marine biodiversity.”
The study, published in the journal Nature Ecology & Evolution, marks an optimistic step towards ensuring that the growing field of mariculture can expand responsibly, protecting our oceans while meeting the nutritional needs of a growing global population.