Grant funds Sarker's aquaculture sustainability research

Pallab Sarker is an assistant professor of environmental studies at UC Santa Cruz.

It’s not often that professors receive significant awards without applying for them specifically — but Dr. Pallab Sarker was fortunate enough to be the recipient of such a rare and coveted experience.

Earlier this year, Sarker received a foundation grant fund from the Cynthia and George Mitchell Foundation, amounting to $170,947 over three years to strengthen his lab’s ecological aquaculture work. The funding was “unsolicited,” said Sarker, but stemmed from his professional relationship with one of the Foundation’s board members Dr. Greg Mitchell, who advocated for Sarker to the Board to receive funding for his projects at the University of California, Santa Cruz.

The Foundation, established in 1978, has distributed or pledged an estimated $900 million in grants toward issues relating to sustainability across the U.S., with a goal to ensure long-term human and ecosystem well-being.

Sarker — who first joined UC Santa Cruz’s Environmental Studies department in 2019 — has worked diligently throughout his career to research shifting aquaculture, the world’s fastest growing food sector, in relation to sustainability surrounding aquafeeds. As he explained, shifting aquafeeds toward more sustainable ingredients helps the life cycle of environmental effects on aquaculture, and can change the future of aquaculture diets.

“Aquaculture is increasingly dependent on terrestrial crops, such as soy and corn, and wild fish for feeds,” he said. “That can be damaging to aquatic ecosystems…especially when aquafeeds now use over 70% of the world’s fishmeal and fish oil for unsustainably sourced forage fish.”

That is paired with the challenges for fish to digest the feeds, Sarker explained. Fish cannot digest the majority of the crops’ phosphorus, which leads to phosphorous emissions.

To address that issue, Sarker’s team at UC Santa Cruz is working on circular economy research, aiming to reuse nutrient-rich aquaculture water to grow vegetables at the Ecological Aquaculture facility and the Center for Agroecology on campus. 

Aquaculture has found its popularity rise in recent years, as scientists look to advance the possibilities of its relationship to global food production for the rising population. According to an October 2022 article by researchers at Cornell University and University of Washington, food production from marine algae-based aquaculture has the potential to contribute more than the total global protein demand projected for 2050. Further, aquaculture offers important nutritional and environmental sustainability advantages relative to terrestrial agriculture.

Here in Santa Cruz, Sarker is using microalgae instead of fish meal and fish oil to develop aquafeeds for more sustainable aquaculture. It will help reduce the pressure on  the main components of the “marine food web,” including many of the most popular fish options for diners the world over: sardines, anchovies and herring. 

Further, he said, “we are aiming to develop ocean-friendly and low polluting aquaculture diets for rainbow trout,” by using underutilized microalgal co-products and leftover biomass after oil extractions in their research.

“Aquaculture is the fastest growing sector, and this rapid growth increases environmental impacts and feed inputs,” he said.

The grant from the Cynthia and George Mitchell Foundation accounts for only one of the two USDA grants Sarker is currently overseeing, with the other grant amounting to $1 million. With the funding from these groups, Sarker’s main objective is to develop new protein ingredients by converting micro-algae industries and large volumes of underutilized co-products into value-added ingredients, which are both cost viable and environmentally beneficial, toward the rainbow trout feed.

“This work advances the nutritional and economic feasibility of an environmentally sustainable aquaculture diet,” he said. “This is the key success factor for growth in the United States’ and in California’s aquaculture industries.”

Already, Sarker has been able to share some of his work with the global sustainability communities through Mitchell to the Cynthia and George Mitchell Foundation. He attended and lectured on his research at the Algae Biomass Summit in 2021, one of the largest algae conferences in the world, and World Aquaculture Society  triennial Algae in Aquafeeds workshop organized by ABO FAAF in 2022.  Sarker also will attend, by invitation of Mitchell, to teach the sustainable aquaculture course and microalgae aquaculture feeds to the students at Prairie View A&M University in the summer of 2023.

Looking forward, those experiences have helped set the stage and the funding for Sarker’s continued research in aquaculture. His lab currently has 10 undergraduate students and one PhD candidate working together, all of whom Sarker says are “very passionate” about the research, which makes the process all the more enjoyable and important.

“So many students learn about the sustainability of aquaculture and our research here at the UCSC farm…that’s what’s important for us to integrate aquaculture into the conversation,” he said. “Community engagement is huge — this work has a huge impact on our understanding of aquaculture and how we can work together into the future.”