Kelly Benoit-Bird studies ocean organisms smaller than a microchip and bigger than a luxury motor home — the tiniest crustaceans to the mightiest cetaceans. In effect, she studies just about anything that swims or drifts in the sea: copepods and krill, diatoms and dinoflagellates, siphonophores and salps, spinner dolphins and Humboldt squid, Pacific sardines and sperm whales. Not only is she unbounded by species classifications, she also is unrestrained by the dimensions of time and space. What drives her research is, indeed, the traversing of those very dimensions by animals and plants in search of survival.
As a pelagic (open-ocean) ecologist, Benoit-Bird investigates the intricate interactions among predators and prey that take place day and night, full moon to new moon, summer to winter, El Niño to La Niña in Earth’s vast oceans.
“Despite the apparent variety of the ongoing research projects in my lab, all of our research aims to understand the role of spatial and temporal patterns in ecological processes on spatial scales ranging from sub-meter to hundreds of kilometers, at temporal scales of minutes to years, and over a range of animal size from zooplankton to great whales,” Benoit-Bird explains on her webpage for Oregon State University’s College Earth, Ocean, and and Atmospheric Sciences.
The challenge is almost beyond imagining. Within the world’s 326 million cubic miles of seawater, most species interactions happen where humans cannot witness them. Besides, as Benoit-Bird points out, the marine environment is in constant motion. On land, plants hold fast to the ground. Forests may be complex ecosystems to study, but at least they stay put. At sea, plants drift on tides and currents, rising and falling in the water column with the sun and the moon and the seasons.
“In the ocean, plants are incredibly small, have very little structure and move all over the place — sometimes even actively,” the researcher says. “Some of the plants can swim.”
To compensate, Benoit-Bird extends her senses. She devises novel acoustic and optical technologies that collect data remotely, giving scientists a virtual front-row seat on some of nature’s most mysterious processes. Her innovations are opening the world’s oceans to human understanding in ways never before possible. In 2010, the John D. and Catherine T. MacArthur Foundation recognized her pioneering work with a prestigious $500,000 MacArthur Fellowship — popularly known as a “Genius Award.”
Life in Layers
Instead of being like a big pot of soup with its ingredients evenly mixed, the ocean is more like a big blue torte with dense congregations of organisms layered vertically, Benoit-Bird and other oceanographers have learned in recent years. In coastal waters across the planet, scientists have discovered that plankton, both in its plant and animal forms, coalesce into layers two or three feet thick, sometimes extending for miles horizontally. These “thin layers” of tiny life forms — which Benoit-Bird calls “great smorgasbords of food”
— likely hold critical clues to how ocean ecosystems work.
“While thin layers are just beginning to be investigated,” Benoit- Bird writes in a recent issue of Continental Shelf Research, “thin layers are likely to be important for a variety of biological processes, including growth rates, reproductive success, grazing, predator-prey encounters, nutrient uptake and cycling rates, as well as toxin production.”
To get inside those mysteries from the deck of a research vessel, Benoit- Bird has been developing a whole new generation of tools. She uses sonar technologies to collect acoustical data that are then fed into computers for analysis. To broaden their options, she and her collaborators have experimented with linking disparate gear types, such as video cameras and echosounders (devices that locate layers and schools of organisms by sending out pulses of sound waves). They’ve designed new uses for old standbys, like retrofitting a remotely operated vehicle (“a little tethered robot”) to find and track plankton layers by following water density. They’ve invented a new kind of sonar to study the distribution of individual zooplankton inside thin layers.
Her ambitious research goals, supported by the National Science Foundation and other agencies, necessarily push her toward more expansive technologies.
“My perspective is that we shouldn’t be limited by the tools we have,” she says. “I like to think about the question first and figure out how to address it later. It may mean we have to develop a new tool or a new way of analyzing data or a new way of deploying instruments to get at the questions we’re interested in.”
A “Spatial Ballet”
Computer animations created from recent acoustical studies show fish diving through plankton layers, gobbling holes in the tightly packed, food-rich patches. Another animation shows spinner dolphins swimming in tight formation to corral layers of lanternfish during coopera- tive feeding.
“The emerging picture is one of an incalculably complex, finely tuned, and delicate interaction between predators and prey, chemistry and light, currents and water column, night and day,” writes author Julia Whitty in a recent Mother Jones article featuring Benoit-Bird. “Some semblance of this spatial ballet, played in weightless three-dimensional darkness, has likely been part of the oceans since the oceans were brought to life: layers of life gathering in extremely high densities to feed or to avoid being eaten.”
Article courtesy of Terra Magazine
Photo by Craig Mitchelldyer (Getty Images for the McArthur Foundation)