TOPP Secret

Tucked behind Monterey’s famous aquarium, where summertime crowds line up around the block to gawk at fish in tanks, the Hopkins Marine Station has been quietly studying the marine life you rarely see. Over the last decade, the research institution has coordinated a massive tagging and tracking effort to find out what the Pacific’s inhabitants do when we’re not looking. Now that the TOPP—or Tagging of Pacific Predators—program is drawing to a close, its data is providing a detailed look at a complex ecosystem, offering clues about how to conserve endangered species, and inviting public involvement through a remarkable partnership with Mountain View-based search engine Google.

Since 2000, TOPP has involved some eighty scientists who have tagged more than 4,000 animals, collecting more than a trillion individual data points recording the movements of 23 predatory species like white sharks, bluefin tuna, and elephant seals. Why only predators? Imagine observing the Serengeti, says TOPP marine biologist Randy Kochevar: If you followed the lions and hyenas, you would also find their herbivore prey, who would in turn lead you to the landscape’s resources, like watering holes and plant life. “Our theory is that we can do the same thing in the ocean,” Kochevar says. “If you just focus on these apex predators you really start to get a sense of how the whole ecosystem is working.”

TOPP data shows that the Pacific Ocean contains the equivalent of “watering holes,” or multi-species hot spots where animals gather to eat and breed. These hot spots coalesce where upwellings of nutrients cause plankton to bloom, in turn attracting small fish, then bigger fish, and so on up the food chain. Between these hot spots are migratory corridors, the highways of the underwater world. Until recently, humans didn’t know much about the travels of highly migratory animals like sharks and tuna, most often spotting them where these highways run close to the coasts. But that, says Kochevar, is “like standing in your backyard and watching a jet fly over—you’re just getting a glimpse of a much larger journey.” With the tags, he says, “It really opens up a whole new world because you start being able to see where the animals are day to day.”

Scientists are now overlaying this tracking data with other oceanographic information like water temperature, sea surface height, and currents, to better understand why animals roam where they do, and which areas are particularly important to their survival. Up until now, regulators working with limited data have attempted to protect species via fairly blunt mechanisms like limiting catch—but as Kochevar points out, these policies are “oftentimes not necessarily based in a good understanding of the animal’s life history, or where they are when, or what’s critical habitat.” Instead, TOPP scientists hope that providing very specific data about how animals use the ocean will help us protect them, perhaps by influencing where we site shipping lanes, Marine Protected Areas, offshore drilling or wave energy plants, showing where we must control pollution and shoreline development, and helping us be smarter about how we fish.

Take, for example, the case of the rapidly disappearing leatherback turtles. “They are the ancient mariner of the sea turtle world—the widest ranging, largest existing sea turtle, the most prolific breeders that dive to the deepest depths, and swim in the coldest waters,” says Stanford researcher George Shillinger, who started tagging them for TOPP in 2003. “They’re just enigmatic and beautiful creatures.”

Indeed, the life of the leatherback is mysterious—although they live for forty years, most of that is spent at sea. Humans don’t see them except during their brief onshore nesting periods. “You see them as little hatchlings and then they disappear for ten to twelve years,” Shillinger explains. “Somehow or another, against all odds, they return [to breed], and then they go away again. For [another] four years they disappear out into the vast expansive blue, and then they come back. How do they do that? It’s incredible!”

Yet leatherbacks are in serious trouble. Shillinger says that over the last two decades the Pacific basin population has declined by over ninety percent. (The World Wildlife Fund estimates that only 2,300 adult females remain in the Pacific, and around 34,000 worldwide.) In the hope of figuring out how best to aid them, Shillinger has been tagging turtles on Costa Rica’s Playa Grande, their last remaining viable nesting colony in the eastern Pacific. Even there, the turtles are threatened by the harvest of eggs from their nesting
spots, habitat loss due to coastal development, light pollution that confuses them as they swim to sea, and deaths from eating plastic, which the turtles mistake for their favored prey, jellyfish.

But their biggest threat is fishermen. “The advent of cheaper fuel and new fisheries technologies has pushed a lot of fleets offshore, where the migrating turtles, when they head out to their foraging grounds, interact with fisheries in distant areas. They are hooked by long liners or they drown in gill nets,” says Shillinger. The loss of a single adult female is “a tragedy for the turtles,” he says, because of their low reproductive rate: A female may produce 2,400 eggs in her lifetime, of which only two will survive to adulthood. The irony, says Shillinger, is that nobody wants to kill leatherbacks; there isn’t a market for them, and when fishermen do hook them it causes a work slowdown and a PR embarrassment. Shillinger hopes to use the TOPP data to keep the turtles and the fishermen out of each other’s way.

This might not be so hard: tagging data shows that after their nesting period, the Playa Grande turtles follow a consistent path from beach to sea. “That in and of itself affords a fantastic opportunity for conservation,” says Shillinger; options include closing off that corridor to fishing fleets for the three months it takes the turtles to migrate across it, or just shutting down smaller sections while the turtles are passing through. Alternatively, tagging data showing the depths in which the turtles prefer to swim could be used to help fishermen to adjust the lengths of their lines to avoid hooking them. None of these solutions is as drastic as creating a permanent no-fishing zone; TOPP scientists hope highly targeted, short-term adjustments like these will be more palatable to the fishing industry, since it won’t eliminate anyone’s livelihood.

In April, Shillinger headed to Costa Rica to discuss his data with representatives from the ministry of environment, the parks service, and the fishing industry. He hopes to eventually see a regional conservation effort involving the nearby nations of Ecuador, Panama, Nicaragua, and Colombia, because as he puts it, “These animals obviously don’t abide by political boundaries.” He thinks international conservation efforts should also start looking ahead to future issues, like the effects global warming could have on leatherbacks. Sea level rise might be bad news for Playa Grande, and “If we don’t anticipate where the next great nesting beach might be, they might not have anywhere to go, especially with runaway development along the coastal areas,” he says.

But while the TOPP data hints at a way to help the leatherbacks, it’s also given us some gloomy news about other species. For example, TOPP pays a small fee to fishermen who return the tags from any tuna they’ve hooked; an unexpectedly high percentage of tags are being returned soon after deployment, suggesting that they are being harvested more intensively than previously thought. Even with animals that aren’t commercially fished, like white sharks, Kochevar says, the tagging team is “finding that we’re seeing the same animals again and again and again. … It suggests that, you know what, maybe there aren’t really that many white sharks.”

So as TOPP winds up its first phase, it faces two new challenges: communicating its findings to people who can push through conservation measures, especially for animals that are critically endangered, and broadening its efforts internationally. Its successor is a new project called GTOPP, or the Global Tagging of Pelagic Predators, which will invite scientists from around the world—not just California’s side of the Pacific—to pool their tracking data via Google Earth, the massive digital mapping project devoted to “annotating the globe.” Google Earth’s ocean maps (downloadable at www.earth.google.com/ocean) provide 3-D topographic images that allow viewers to “swim” around the underwater geography. TOPP is overlaying its animal tracking data onto these maps; click on the image of a shark or a leatherback and you can see where it’s been. Come back tomorrow, and see if it’s moved. Using Google is a way for scientists to easily exchange information—but it’s also a way to communicate with another ocean policy stakeholder: you.

“It seems like an interesting way to grab people’s attention and get them to be excited about exploring the planet,” says Google’s Steve Miller, who is working on the GTOPP project. Making data publicly accessible in real time will let people feel that they are “watching the experiment in progress,” says Kochevar, and has great potential for environmental education because so many of the tagged animals are sharks, tuna, and other “charismatic megafauna”—that’s scientist-speak for “really cool big animals” that capture the public’s imagination and arouse compassion. Since the data about those animal’s lives will always be updating, says Miller, “If a kid happens to fall in love with a particular whale shark, he ought to be able to come in every day and see where it’s going,” and maybe learn about its environment and challenges in the process.

For policymakers, dynamic mapping could make it easier to visualize and debate complicated conservation issues. This spring, Miller and other Google representatives met with congressional staffers on commerce, science, and natural resources subcommittees who were interested in using digital maps to help legislators evaluate the potential impacts of, for example, offshore wind, gas, or oil developments.

Google Earth’s maps have already been useful tools for environmental activists with more terrestrial concerns: In the Santa Cruz mountains, Neighbors Against Irresponsible Logging (NAIL), used Google Earth to illustrate how a proposed logging zone would encroach on residential areas; in North Carolina the group Appalachian Voices created a virtual tour within Google Earth showing the effects of mountaintop removal coal mining. Making TOPP’s tracking data public could be a boon for ocean conservation groups; Miller points out that UC Santa Barbara scientists have been using Google Earth’s ocean maps to discuss Marine Protected Areas.

TOPP’s tracking data is giving us our clearest picture yet of life in the Pacific—will better data ultimately mean better ocean health? Kochevar thinks so: “The only way that conservation can really work,” he says, “is if you’re working with the right information at your fingertips.”


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