Dr. Dong-Fang Deng: Researching Aquaculture Nutrition

Meet Dong-Fang. She’s a nutritionist researching better fish feeds to support the aquaculture industry and conservation efforts. Dong-Fang works with students ranging from high school interns to international postgraduates. Her dynamic team learns from one another as they tend to many species of fish—including yellow perch, rainbow trout, Atlantic salmon, tilapia, and even lake sturgeon—in the School of Freshwater Sciences’ extensive aquaculture lab.

In Milwaukee, Dong-Fang is pushing at the frontiers of the global aquaculture industry as a whole.

As the human population continues to grow and global fisheries face further stress, aquaculture is expected to become an increasingly significant part of humankind’s portfolio of food strategies. Fish are nutritious and—relative to other animal protein sources like cattle or pork—require less feed to produce the same amount of product. But there’s a catch. Most fish feed comes from wild-caught fish. In order to raise fish sustainably, alternate protein sources for fish feed are therefore in high demand.

Dong-Fang notes that much research has been done exploring soybeans and corn as a “next generation” fish food, but the drawback to relying on those crops is they require a lot of land, energy, and water. Dong-Fang and her lab are interested in exploring other fish meal alternatives, including algae, duckweed, food waste, or even insect protein. Dong-Fang’s current research in 2020-2021, funded by the U.S. Department of Agriculture, explores alfalfa leaf protein. If this strategy proves viable, she notes it would help both the aquaculture and agriculture industries by dramatically expanding the market for alfalfa crop.

She finds her work motivating. “If you feel that your work can help out society, can help out the industry,” she says, “you have the passion.”

Dr. Ryan Newton: Discovering New Microbial Communities

Meet Ryan. Dr. Ryan Newton at the UW-Milwaukee School of Freshwater Sciences has the exciting privilege of exploring life at the microbial frontier. His lab is discovering new communities of microorganisms that live in our sewer pipes and our Great Lakes aided by technologies that weren’t even invented yet when Ryan was in grade school.

Just as the invention of the telescope allowed astronomers to observe and catalog distant stars and galaxies—leading to a fundamental shift in our understanding of our place in the universe—recent advances in genomic sequencing and microscopy have opened up a new realm of discovery, allowing scientists like Ryan to learn totally new knowledge about freshwater microbes that no one has before. “It’s a great time to be a microbiologist and exploring life on this planet,” he says. Ryan’s work has helped reveal a major surprise about the microbes inhabiting urban sewer systems—with global implications.

Dr. James Price: Researching the Economics of Water

Meet James. He’s an assistant professor and environmental economist at the UW-Milwaukee School of Freshwater Sciences. What does economics have to do with water science, you might ask? Actually, a lot.

“Economics as a discipline does recognize that environmental natural resources have tremendous value,” James says. “It's just that these things are not oftentimes accounted for in policy decisions. Some of the work that I'm doing is to try to fill in those gaps in order to improve those decisions and outcomes.”

One of those gaps involves how we value the quality of groundwater in Wisconsin. James specializes in nonmarket valuation, a field of economics that assigns quantitative values to environmental goods and services—like water quality—that are not directly traded on markets. His current research covers all groundwater drinking water plants in the state, which are responsible for serving 42% of Wisconsin’s population with clean water. James is exploring the relationships between the quality of source water and the cost of treating that water. “Once we have that information, drinking water treatment plants can use it to look at the tradeoffs between, say, treating drinking water in plant versus protecting source water prior to entering [the system].”