As sharks continue to move through the water, they do more than hunt prey or cross ocean basins. They help us see the ocean more clearly, filling in gaps that have long limited our ability to predict what’s next.
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Somewhere out in the Northwest Atlantic, a blue shark (Prionace glauca) glides through shifting layers of water, plunging hundreds of feet below the surface before rising again. He is hunting, navigating, living his (best) life. And yet, every move he makes allows a piece of technology on his fin to record temperature, depth and location. A trail of data that, until recently, was primarily used to understand the shark itself. Now, however, the same data is helping scientists better predict the future of our planet.
I mentioned before Dr. Camille MLS Pagniello‘small study where salmon sharks (Two-way beam) They attached a new custom tag, called the CTD-SRDL, “allowing researchers to track temperature and salinity profiles while tracking the shark’s natural movements.” The data collected by the tagged shark was then compared with measurements from Argo floats in the same area, and while both data sets provided valuable information, the shark data revealed much finer detail in some areas, particularly in dynamic zones shaped by eddies and coastal interactions. Marine predators such as sharks actively seek out dynamic ocean features such as fronts and eddies, areas where different water masses collide and mix. These areas are biologically rich and physically complex, and are where traditional observing systems struggle to keep up. While satellites can tell us a lot about the surface of the ocean, they can’t see very far beyond it. And while buoys and research vessels provide detailed data, they are also limited in coverage and expensive to maintain. The ocean is vast and much of it remains under-sampled. The sharks, on the other hand, are already there.
This news study was published on npj Climate and Atmospheric Science led by Woods Hole Oceanographic Institution scientist Dr. Laura H. McDonnell based on Pagniello’s idea. In their study, the team tagged 18 blue sharks and one shortfin mako shark (Isurus oxyrinchus), equipping them with satellite-linked devices capable of recording temperature and depth alongside location data. As these animals moved through the ocean, they transmitted more than 8,200 temperature-depth profiles, reaching depths of nearly 6,562 feet (2,000 meters). The research team then took a subset of that data and fed it into a seasonal climate model, a model that is part of a larger forecasting system used by scientists to predict ocean and atmospheric conditions. They compared forecasts generated with and without shark data and were able to significantly improve the accuracy of ocean forecasts thanks to sharks, particularly in coastal areas and areas where conditions can change rapidly and where accurate forecasts are particularly important for ecosystems and human activities. In fact, by incorporating the data collected by these mobile ocean sensors into climate models, some surface ocean forecast errors were reduced by as much as 40 percent!
What does it say about our relationship with the natural world when an animal we often fear becomes a partner in understanding climate change?
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So while scientists won’t have to worry about sharks taking over their jobs as oceanographers, they may have them as “colleagues” in a way. Because if 19 sharks can make a measurable difference, what could hundreds or thousands? What about other marine animals that travel different routes or occupy different depths? There is already a growing field of research exploring animal sensors, from seals that measure polar conditions to turtles that monitor coastal environments. Sharks now add another layer to this picture, particularly in areas where they naturally cluster around ocean features that matter most for climate dynamics. “Tagged sharks will not replace conventional observation systems,” McDonnell said in one press release. “What the preliminary results show is that tagged marine predators can provide complementary in-situ observations at the surface and at depth.” But even as a supplemental tool, the features are compelling. Better ocean forecasts can improve fisheries management, helping to ensure that seafood supply chains remain stable and sustainable. They can support maritime operations by providing more accurate information about sea conditions. They can also deepen our understanding of how climate variability affects coastal communities, many of which already face increasing uncertainty.
Sharks are often presented as threats, limited to headlines and the stereotype of the “bloodthirsty killer”. Yet here they are, contributing to one of the most complex scientific challenges of our time. It makes you wonder how many other neglected connections are out there, waiting to be recognized. If a shark can help improve a prediction, what else might be possible when we begin to see the natural world not just as something to study, but as something to learn from in entirely new ways?
