Published October 26, 2016 by Rebecca Goldfine

Becca Selden ’06 Looks to the Sea to Study Climate Change

Becca Selden ’06 on a recent visit to Bowdoin
Becca Selden ’06 on a recent visit to Bowdoin

Marine ecologist Becca Selden studies fish populations. But to better understand fish, which are threatened by climate change and harvesting, she also has to understand people. Besides researching the dynamics of ocean ecosystems, she also studies how fishermen in coastal communities are changing along with our changing oceans.

Currently a National Science Foundation post-doctoral research fellow at Rutgers University, Selden’s curiosity about oceans began as a child, when she explored tide pools on family visits to southern California. At age 11, she went snorkeling for the first time and recalls how amazed she was to discover a colorful, mysterious world invisible to those on land. She knew early on she wanted to devote her life to marine biology.

Selden recently returned to Bowdoin—the place where her childhood wonder began the transformation into adult expertise—to give a talk and meet with students interested in marine biology careers. She told students how invaluable it was to her to be able to collaborate with a faculty mentor here—Amy Johnson, Bowdoin’s James R. & Helen Lee Billingsley Professor of Marine Biology. As a junior and senior, Selden received a Beckman Scholarship to support her research with Johnson. They studied whether the scent of crab predators would alter sea urchin morphology and development.

Selden urged students to take advantage of the research opportunities available to them at Bowdoin. “None of my friends who wanted to do research here were turned away,” she said.

After graduating from college, Selden traveled the world on a Watson Fellowship, studying sea turtle conservation in small communities in South Africa, Malaysia, the Cayman Islands, Australia, and Panama. During this year of travel, her thinking about marine conservation began to shift.

“My generation of scientists is looking at having their work make an impact,” she said. “We have observed in our lifetimes the decline of species, even extinctions. We have a profound appreciation that our actions are influencing ecological systems.”
—Becca Selden ’06

She described evolving from an idealistic young girl focused on conservation—and saving animals like leopards at any cost—to a seasoned scientist who is mindful of how important natural resources are to sustaining people throughout the world. “I realized that people can’t just up and stop what they are doing,” she said. “So working with communities to design solutions that are more of a win-win is the way to go. I’ve gone all the way to the other side. I don’t see any marine life as overly sacred. Millions of people rely on seafood for their main source of protein.” Instead, she concluded, she wants to see better, more sustainable management of fisheries.

Selden’s interest in the complexity of sustainability steered her graduate studies. At the University of California, Santa Barbara, Selden looked more deeply into “the ecology of a marine system that was embedded within our socioeconomic system, one that people are dependent on for their livelihood.” There she investigated the effects of smaller-sized California sheephead, whose body sizes have decreased due to overfishing, on sea urchins (which sheephead like to eat) and on kelp forests. Kelp is a critical habitat and food source for many species and disappears when there is an overabundance of sea urchins. “We lose biodiversity when we mess with species in this way,” she said.

In her recent research, Selden has been looking at how fishing and climate change are affecting predator-prey relationships along the Atlantic seaboard. She is also investigating how fishing communities are adapting, or not adapting, to climate change and shifting fish populations.

“In the Northeast, we’ve seen rapidly warming waters and in response, species have shifted farther north,” she said. “One is the American lobster, which has moved its center of distribution 200 kilometers north over the last four decades.”

While that has been good for lobstermen in Maine, it has hurt lobstering communities south of us. “Because it is such a valuable fishery, each boat has a territory and is somewhat aggressive about maintaining that territory,” Selden said. “That makes it difficult for fishermen to move as their fish move.”

Two top fish predators Selden has been focusing on are cod and spiny dogfish, which eat, among other things, lobster and herring. Predators are important to the entire food web, and if they are reduced, it sends shockwaves through the ecosystem, leading to dramatic changes in other species. Cod, a popular cold-water species, has been vastly depleted from fishing. Meanwhile, spiny dogfish prefer warmer waters and are not, at the moment, a preferred fish to eat.

Selden predicts that in a warmer world, cod will not fare well. “The geographic range of cod will decline as water warms and carbon dioxide increases,” she said. Even if we stopped fishing cod entirely to return the depleted cod stocks to their former glory, cod will decline, she added.

However, spiny dogfish could move in and take over the functional role of cod. “From an ecosystem perspective, this is potentially good news, in that the impact on the forage community may be small because there could be compensation from a warm-water predator,” Selden said. “The net ecosystem effect might be neutral.”

Selden said that no matter where she ends up in her career—at a government research center or at a liberal arts college—she wants to be involved in marine resource policy. “My generation of scientists is looking at having their work make an impact,” she said. “We have observed in our lifetimes the decline of species, even extinctions. We have a profound appreciation that our actions are influencing ecological systems.”