Science Is Turning the Tide for the Global Ocean

Did you know that a bluefin tuna can weigh up to 1,500 pounds and dive deeper than 3,000 feet? Or that 130 million metric tons of plastic enter the environment annually – equal to roughly 40 pounds per person worldwide? Or that seagrass provides nursery habitat and breeding or feeding grounds for 20% of the world’s largest fisheries, including cod, pollock and herring?

You can thank science for these and other fascinating facts that have boosted understanding of the environment and the steps needed to protect it.

And science will play a key role during the Our Ocean conference later this month, when hundreds of the world’s ocean advocates will gather in Kenya to discuss issues ranging from pollution to overfishing. It’s the first time that Africa is hosting the event, which was founded in 2014 by then-U.S. Secretary of State John Kerry to bring governments, scientists, businesses and conservation organizations together to drive action to protect the global ocean. Kenya is also hosting the first Our Ocean science symposium, to be held before the conference, where researchers, policymakers and innovators will explore how science and evidence can drive practical solutions.

When science underpins conservation efforts, it reveals not just what’s happening in the ocean but also why it’s happening, how quickly conditions change and which solutions may work best. From satellite mapping that locates seagrass meadows to electronic tagging that tracks fish movements throughout the ocean, diverse scientific research is happening around the world to address major challenges, including climate change and biodiversity loss. With accurate data, policymakers, communities and conservation groups can identify threats early, use evidence to inform decisions, and measure whether protections are delivering results and keeping pace with rapidly changing conditions.

Science also turns the ocean from something vast and mysterious into something that people can relate to and better understand. Researchers can track how a discarded plastic bottle washes through storm drains, rivers and coasts, eventually making its way into the seafood that people eat and the water that they drink. They can measure how mangroves and seagrasses capture and store carbon and lessen flooding that can damage coastal communities. And they can show how healthy fish populations support commercial fishing jobs, tourism and affordable food for millions of people worldwide. By making those connections visible and measurable, science gives governments and communities the information they need to direct resources where they can do the most good – whether it’s restoring habitats, creating marine protected areas, reducing pollution or sustainably managing fisheries.

At The Pew Charitable Trusts, we support science-based research and policymaking across many conservation topics. Here are three that could inform Our Ocean conversations:

• Fisheries management: After decades of severe overfishing of some of the world’s most valuable tuna species, including bluefin, a remarkable turnaround is happening. Despite continuing declines in many other fisheries, 87% of tuna and tuna-like species are at sustainable levels today, according to the United Nations Food and Agriculture Organization. And fisheries managers have begun to adopt a science-based long-term approach known as harvest strategies, which set pre-agreed targets that automatically raise catch limits if data shows that a species is healthy, or tighten them if the population declines. The successful use of harvest strategies for many of the world’s tunas has changed the future for these prized fish and shows how international cooperation and science-based policies can help to rebuild even heavily depleted marine species.
• Plastic pollution: For years, scientists have been using global modeling, waste-stream analysis, satellite monitoring and health research to track how plastic moves through the environment – not just in the ocean, but also across land and waterways and even in the air – and have been raising the alarm about the harm that plastic is causing to ecosystems, wildlife and human health. Pew’s “Breaking the Plastic Wave 2025” report found that on its current trajectory, plastic pollution worldwide is set to more than double by 2040, reaching the equivalent of nearly a garbage truck per second of plastic polluting the environment. Plastic pollution is fundamentally a systems problem: Plastic production is growing faster than the world’s ability to manage the resulting waste. Yet Pew’s research also shows that solutions already exist, and ambitious, coordinated global action to reduce plastic production, improve product and system design, increase and enhance waste management and embed transparency throughout the supply chain could dramatically cut plastic pollution – by an estimated 83% – over the next 15 years. The challenge is no longer discovering what works scientifically or technologically; it is implementing proven solutions and laying the groundwork to bring innovative ideas to scale at the speed needed to protect people and the planet.
• Seagrass mapping: Scientists in Jamaica and Seychelles used satellite imagery, underwater surveys and sediment sampling to map seagrass meadows and to measure the carbon they store. The research provided some of the first reliable data on where these habitats exist and how they help countries to build climate resilience. That data in turn has directly informed policy and continues to provide insight into where more protections are needed. The findings helped the governments of Jamaica and Seychelles to incorporate seagrasses and mangroves into national climate strategies and conservation commitments. The success of the work also became the foundation for a broader effort now underway across Kenya, Madagascar, Mozambique and Tanzania in eastern Africa to map and better manage seagrass ecosystems.

What unites every success story – from restoring fisheries to protecting coastal habitats – is a simple truth: When science guides conservation, progress follows. Data, collaboration and long‑term commitments can turn the tide on even the most complex environmental challenges. As global partners meet in Kenya, the world has a chance to embrace evidence‑based actions that protect ecosystems and communities alike.

Roger-Mark De Souza is a vice president at The Pew Charitable Trusts, leading the organization’s work on environmental conservation.