For all of our history, the face of the ocean has concealed its teeming life from humanity: now, Laureate Barbara Block is tagging marine predators to reveal their secret lives, their pathways, and their prospects of survival in the Age of Man.
From a swelling torrent of data supplied by thousands of individual sharks, tuna, marlin, whales, seals, turtles and seabirds, scientists are assembling the first detailed picture of life within the oceans – where it goes, where it gathers, how, when and why. Astonishing discoveries are emerging about the web of living things that enmeshes the globe, which promise to transform our understanding of our planet.
Pioneer of the technology of open ocean observation, 2012 Rolex Laureate Barbara Block is driven by a lifelong awe of the sea and a fascination with its creatures. This goes back to a childhood spent on Massachusetts beaches, to youthful cruises on sailing ships and a 32-year calling as a marine physiologist and professor at Stanford University.
She is a world leader in a scientific endeavour to understand life within the oceans through the power of computing and telemetry. Attaching smart electronic tags to large fish, sharks, whales and other sea creatures, and harvesting the results, Barbara’s team has watched in wonder as their secret lives unfold.
Among their most remarkable discoveries are three prodigious seasonal “hot spots off the California coast that draw sea life – especially predators – from across the Pacific in thousands. Block calls this region the Blue Serengeti for its semblance to the great game reserves of Africa where predators still range free; it is the focus of her Rolex project and her wish to study, understand and conserve the life in the oceans.
Loss of top predators
“Overexploitation of living resources is one of humanity’s most pervasive impacts in the sea. Large animals, which were once ubiquitous across the ocean realm and were major forces in ecosystem dynamics, have declined,” she explains. “The loss of these top predators has had cascading impacts, disrupting the services the oceans provide to us and the planet, and, in some cases, completely altering marine food webs.”
The California Current, which bounds North America’s western coastline, appears an exception: here, seasonal upwellings from the deep ocean, rich in food, support teeming sharks, seals, tunas, whales, albatross and sea turtles – a phenomenon she terms the “predator cafe”. Using smart technologies, Block and her team eavesdrop on who comes to dine there, recording their comings and goings. From these fragments of marine gossip, an elaborate picture is emerging of an entire ecosystem at work, its highways, byways, diners and gathering places. This will inform the task of protecting its species and its integrity – and managing the human activities that impact on them.
“Our objective is to study the whole Pacific realm, to observe how the largest ecosystem on Earth works, from the top down,” she says. Already, the tags have revealed that populations of sharks and tuna from California are connected to populations off Japan and Australia, and a picture is crystallizing of species that migrate across thousands of kilometres of ocean, year by year, to dine at the same “cafe”. Over time, the behaviour of certain “sentinel” species will enable scientists to build a report card on the health of the world’s oceans, to guide their management.
Block says the Rolex Award will make a profound difference to gathering data – and to public awareness of the work, an essential element to her ultimate goal of protecting the oceans. It will fund the construction, testing and deployment of three listening buoys, to be located in marine sanctuaries at three California hotspots; in effect she is turning the “predator cafés” into wireless hotspots, like those humans frequent on land. Each time a tagged creature swims within half a kilometre of the buoy its presence will be reported to a chain of Iridium satellites, circling high above the earth, and thence to Block’s laboratory, the desktops of marine managers, and, in a startling development, to the smartphones and computers of ordinary citizens worldwide.
A focus of the project is the Great White Shark, under stress globally from fishing and wanton killing. California is thought to have just 219 adult Great Whites – making it feasible to tag and study a whole population. Besides the scientific data, Block aims to capitalize on the shark’s power over the public mind: for the first time, her project links the lives and travels of sea creatures directly with ordinary people through smartphone “apps” and a website, inspiring them in the same way that visitors to national parks on land are engaged. “People love seeing lions, rhinos and zebras in the Serengeti – and they understand why they need to be protected,” she says. “The challenge is to do that in the oceans, where it is not easy to see the animals.”
Allowing the public to share in the wonder of discovering the life of the oceans will, in time, help build a social consensus for the creation of a UNESCO World Heritage area along the California coast, and support global moves to conserve Great Whites, she believes.
Today, barely one per cent of the world’s oceans is protected, but Barbara Block is determined to play her part in changing that. In the international science journal Nature, she warned: “Without an aggressive effort to zone and effectively manage these resources, the predator populations they support will decline and the biodiversity of this open-ocean wilderness will be irreplaceably lost.”
Published in 2012