On a remote, uninhabited atoll that straddles the equator in the central Pacific, Fiorenza Micheli swims with sharks.
“We scuba dive and look at them and count them,” she says in a mellifluous Florentine accent. “We also put down video cameras because we don’t know a whole lot about their behavior, and it’s probably not safe to dive when they’re most active and feeding.”
Micheli, an associate professor of biology at Hopkins Marine Station, spends a lot of time in the field—at sea. On coral reefs, she studies declining populations of sharks, groupers and parrot fish. In Baja California, she seeks out lobster and sheepshead. Micheli follows different species of sea breams in the Mediterranean, and along the California coast she looks at the effects of sea otters as predators of abalone.
As a field ecologist with a background in animal behavior, Micheli applies theory to practical questions. By studying the foraging behavior of blue crabs in North Carolina (“they’re voracious predators of clams, oysters and scallops”) she was able to recommend guidelines to the National Marine Fisheries Services for seeding shellfish. “They would plant [shellfish], and crabs would then eat them all,” Micheli says. “By finding out where the crabs fed, and at what time, we could come up with a set of guidelines that decreased the mortality of these animals, from over 90 percent of juveniles to less than 40 percent.”
Micheli saw a marine ecosystem in peril and helped rescue it, which is what she’ll be doing as an affiliate of Stanford’s new Center for Ocean Solutions. Launched with a $25 million grant from the David and Lucile Packard Foundation, the center is a collaborative effort among Stanford, the Monterey Bay Aquarium and the Monterey Bay Aquarium Research Institute.
“The primary mission of the center is to deliver the best science to ocean policy,” says interim director Meg Caldwell, JD ’85, a senior lecturer who heads the Law School’s environmental law program. At a time when both the U.S. Commission on Ocean Policy and the Pew Oceans Commission have issued reports detailing threats to marine environments, Caldwell says the center will tap the expertise of oceanographers, marine ecologists, marine biologists, chemists, engineers, social scientists, lawyers and conservation psychologists. They will take aim at the complex effects of overfishing, ocean acidification and climate change, among other challenges.
Micheli and a team of 18 other scientists spent the past three years looking at how 17 different human activities affect ocean ecosystems. In a paper published in the journal Science on February 15, they demonstrate that 41 percent of the world’s ocean waters bear a serious human footprint, with significant damage to coral reefs, seagrass beds, mangrove forests, seamounts, rocky reefs and continental shelves. Although the results “represent the current best estimate” of change, the authors note that “these estimates are conservative and incomplete for most of the ocean.”
“A global analysis of the effects of many different activities on many different ecosystems had never been done,” Micheli says. “The result is pretty astonishing . . . much higher than we expected. If I had to guess before, I would have said 5 or 10 percent, because the oceans are big and most of [their areas] are far from the coast.”
Micheli helped design a questionnaire used to interview some 200 scientists and developed statistical models to interpret the results. Computer models were used—for example, to track invasive species by looking at cargo ships, ballast water, data on shipping lanes and port volumes.
There were surprises, like the “stagnation phenomenon” sometimes found in coastal waters. It happens when fertilizer runoff decomposes on the sea floor, drawing oxygen out of the water and thereby killing organisms. “For the first time, this phenomenon has been documented in an open sea environment,” Micheli says. “There are now no-oxygen zones as big as the state of Delaware that are in the middle of the Gulf of Mexico, in the northern and central Adriatic Sea, the Baltic Sea and many other places.”
Micheli predicts that addressing threats of this magnitude—like bringing back depleted populations of sharks, turtles and tuna in the open oceans, or combating the combined effects of pollution and destruction of habitat in estuary systems—will require collaboration on an unprecedented scale. In her work in Mexico and the Bahamas, she already has enlisted the help of economists and anthropologists, “because to understand what is happening to the ocean, we need to understand what drives the behavior of its users.”
Micheli commutes several times each week between Monterey and Stanford to talk up projects with campus researchers. As she plans the next phase of her work on Palmyra Atoll, she’s seeking some interested anthropologists. “We want to look at fishing patterns of those who live in the Kiribati islands, to see how people use the reef and why, as a way of characterizing the impact of fishing on food webs.”
Given the scale of the problem-solving to come at the Center for Ocean Solutions, Micheli is hopeful. Look at the Mediterranean, she will say. It’s one of the most “impacted” seas in the world, with a long history of use, but in areas that have been protected, some large predatory fish are now returning.
“In some cases the systems that come back may not look exactly like they used to, but they still are functioning ecosystems that provide a series of services. So I think there is a lot of room for hope.”
