Year
2018
Operation Area
North Pacific Subtropical Gyre
Purpose
The white shark is among the most iconic predators in the ocean, but for all their public exposure, the lives of white sharks remain shrouded in mystery. These apex predators are facing an unprecedented worldwide threat from climate change and overexploitation—white sharks are a source of protein for humans across the planet. Critical to protection of apex predators is understanding the oceanic habitats they occupy.
Oceanic ecosystems, from genes to whole organisms and the biogeochemical processes driving their productivity and connectivity, are not well understood. This Saildrone mission, conducted in partnership with Dr. Barbara Block of StanfordUniversity and the Schmidt Ocean Institute, explored the North Pacific Subtropical Gyre (NPSG).
Satellite tagging has revealed that white sharks tagged in the coastal waters ofCalifornia migrate annually to a region called the “White Shark Café,” a virtually unknown area situated in the NPSG halfway between Hawaii and Baja.Why these apex predators leave the productive California coast and migrate offshore, spending months in an oceanic desert, was a mystery.
In 2018, two Saildrone Explorer USVs tracked tagged white sharks with the goal of shedding some light on a long-standing question around their migratory habits. The Saildrone cruise was part of a multidisciplinary team of oceanographers, engineers, marine ecologists, and molecular biologists from four institutions, accompanied by a film team, on an expedition to the Café, including the RV Falkor, who shared a common goal in describing the oceanographic environment and the epi- and mesopelagic ecosystems of the Café, and to locate tagged white sharks and investigate their behaviors in situ to learn why these offshore waters are vital to their life history.
Results
For the first time, physical and chemical oceanography data collected by Saildrone was combined with biological and behavioral data to help scientists to understand the role the White Shark Café plays in this species’ lifecycle.
