Bigger Fish to Fry

IF THERE'S ONE THING ecologist David Lodge, C’79, H’18, has learned in more than three decades of working to solve some of the world’s most intractable environmental problems, it is this: “People love whizbang technology.” That certainly seemed to be the case in September when the Great Lakes Protection Fund presented Lodge with one of its 2021 Great Lakes Leadership Awards, the latest in a slew of honors he has piled up over the years. In particular, the organization cited Lodge’s development of a genetic testing tool called “environmental DNA,” or “eDNA,” to detect the presence of invasive species that threaten the Great Lakes. In 2009, Lodge's team scooped some water out of the Calumet River in Chicago, discovered it contained traces of Asian carp DNA, and, in so doing, warned the world that the voracious species was on the verge of invading Lake Michigan. No one could see the fish, and none had been caught, but like a crime scene detective in a forensics lab, Lodge had proven the bad guys were there. The discovery prompted increased management efforts to keep the carp from laying waste to the Great Lakes’ $7 billion fishery, and it resulted in media coverage for Lodge in outlets ranging from National Public Radio to The Wall Street Journal to The New Yorker. He was soon dubbed the “CSI Great Lakes Guy.”

The award in September was well-deserved and a nice acknowledgment of some critically important work. But for Lodge, who directs the Cornell Atkinson Center for Sustainability at Cornell University, eDNA is just one piece of a broader research effort beginning in the early 1980s to understand as much as possible about invasive species, so much so that he has become one of the world’s foremost experts. At the same time, Lodge has been a pioneer in shaping how science more generally can and should be used in a time when the planet faces so many challenges. That effort is less about flashy technology and more about listening to a wide range of people and working collaboratively with them. “What really motivates me is making vital connections among university researchers across disciplines and with NGOs, corporations, and government agencies to accelerate the movement of knowledge to impact on public opinion, corporate practices, and government policies,” Lodge says. “That’s my job at Cornell, and I love it.”

In essence, it’s a job that Lodge has always wanted, ever since he was a kid growing up in rural Georgia and Alabama, sloshing through lakes and streams and catching turtles and snakes. When he wasn’t catching critters, he was reading about them. It was the 1960s and ’70s, the dawning of the environmental movement, and from a young age Lodge had a sense that he wanted to help the natural world thrive.

Lodge’s father, an Episcopal priest, had gone to Sewanee, and his father before that, and while Lodge had always told himself he wouldn’t follow in their footsteps, he found himself on the Mountain for his freshman year in 1975. He toyed with the idea of majoring in history and was especially intrigued with the classes of History Professor Joe Cushman. But his focus ultimately became biology, and he spent most of his time under the tutelage of biologist Harry Yeatman, ecologist George Ramseur, and botanist Larry Jones. What really shaped his approach to scientific research, however, unfolded two-and-a-half hours northeast of the Domain at the Oak Ridge National Laboratory, where Sewanee at the time had a “semester abroad” program. Lodge did a semester at Oak Ridge and then worked there for two summers in the environmental science division. He did his first real experiments there. One project focused on the use of tilapia in sewage treatment ponds. Another project measured the effects of acid rain on bean plants.

As a senior at Sewanee, Lodge landed a Rhodes Scholarship to study at the University of Oxford. At Oxford, his mentor—who quickly discerned that his charge was ahead of the curve—urged him to switch from the undergraduate zoology program he had applied for to a doctoral program. His dissertation research focused on determining why different species of aquatic snails live in different parts of a pond near the Oxford campus. “It did not produce any scientific breakthroughs,” Lodge concedes. “But it taught me how to do field experiments.”  

Lodge’s research on invasive species began in 1983 during a postdoctoral fellowship at the University of Wisconsin, where he took up work on the rusty crayfish, Orconectes rusticus. He then continued his study of invasives at the University of Notre Dame, a place he spent the next 31 years. More than once during this stretch, Lodge questioned what he was doing with his life. “At Sewanee I said I would never be an academic,” he says. “It seemed like a circular life. I’m going to study, then I’m going to teach people how to study? In college, I had hoped that my many academic interests would end up benefiting society. But academic training beats that out of you.”

In the 1980s the idea of applied science—the very thing that Lodge felt might make a difference —was still viewed as a second-class pursuit.

A pivotal moment for Lodge came in 1999 when he was appointed the first chair of the Invasive Species Advisory Council, a body established by President Bill Clinton’s administration. It consisted of academic experts, representatives from state agencies, and industry people. “From the very first meeting, I learned that the questions that non-academics were asking weren’t the questions that the academics were asking,” Lodge says. “I basically learned that our research was not relevant. It was a comeuppance.” Industry folks were concerned with economic and financial impacts, but ecologists simply didn’t know how to address those areas. Lodge decided to change his research approach. He began cold-calling economists, philosophers, and ethicists and engaging in conversations that expanded what science might address. Over time, his scientific publications went from papers with names like “Reductions in submersed macrophyte biomass and species richness by the crayfish Orconectes rusticus” to “Economic impact of ballast-mediated invasive species in the Great Lakes.” He did a cost-benefit analysis of preventative measures to stop the westward spread of invasive zebra mussels. He led multidisciplinary risk assessments of various other aquatic invasive species.

Lodge’s new approach led him in 2009 to a joint effort with the Army Corps of Engineers to address the Asian carp problem in the Mississippi basin. Decades earlier, catfish farmers in the South had imported the species to clean their ponds, but many had escaped and eaten their way up the Mississippi, devastating native fish populations. The Corps needed to know how far the carp had advanced upriver. “You can’t manage invasive species unless you know where they are,” Lodge says. “For terrestrial animals you can just look around. That doesn’t work so well in water.” Environmental DNA had just been used for the first time by French scientists trying to locate invasive American bullfrogs in wetlands in France. The technology leverages the fact that every animal continuously sheds bits of DNA—skin, feces—and a single cell of floating genetic material can reveal which species are in a waterbody. Lodge’s team was the first in the United States to try eDNA at a large scale. “We went in thinking, ‘This is crazy,’” he says. “But it worked the very first time.”

Since Lodge first used eDNA to detect carp in Chicago, the technology has become commonplace among ecologists, with hundreds of scientific papers published each year based on eDNA research. His lab at Cornell continues to push the technology further. It can now be used to detect not just one or two target species like carp, but most species present in a waterbody, both animal and plant. And Lodge’s research team is getting close to being able to determine genetic variability within the species, which would enable the identification of individuals and estimations of population size. That would provide fisheries officials with all manner of new management tools.

Meanwhile, Lodge continues to press ahead on a variety of non-technical, non-whizbang fronts. He speaks to audiences foreign and domestic about not just invasive species, but also about reducing climate risks, accelerating the energy transition, and increasing food security. He testifies before Congress, executive agencies, and various federal task forces. And he serves on various national and international boards and committees pushing for science-backed policy change. He wishes that humanity wouldn’t need high-tech solutions to deal with the various messes we’ve gotten ourselves into. “Wouldn’t it be better if we hadn’t introduced invasive species in the first place?” he asks, by way of example. “Yes, we’re developing the technology to deal with them, but the focus still should remain on preventing them from arriving at all. It’s a much cheaper solution.”