Plenty of fish in the sea? Not enough to feed 10 billion people sustainably.

Alternative seafood is an important tool to help our oceans thrive while feeding a growing population.

Growing up 30 minutes from the ocean meant the beach wasn’t just a vacation destination—it was a part of my daily life. My Florida upbringing sparked a deep fascination with the sea and a lasting drive to do what I could to protect it. Although some ocean phenomena remain mysterious, one truth is unmistakably clear: overfishing is taking a visible and devastating toll on this vital ecosystem.

Around 90 percent of marine fisheries are either fully exploited or overfished, and pollutants drive biodiversity loss in our ocean as well as riverways and coastal zones. A 2018 study found that more than 55 percent of the ocean surface is covered by commercial fishing—more than four times the area covered by agriculture.

This is not just a problem for the ocean, it’s a problem for the people who depend on it. Currently, the livelihoods of around 3 billion people worldwide depend on the ocean. That number—which is inclusive of people whose main source of protein is seafood and those whose jobs are directly or indirectly linked to the ocean—is only going to keep rising. The human population reached eight billion in November 2022 and is expected to reach almost 10 billion by 2050. Consumption of aquatic foods (farmed and wild) is rising twice as fast as the global population.

We can reduce the burden of overfishing on our oceans to some extent through careful management of fisheries. However, improving management inherently requires setting limits on wild-caught fish production—how much can be caught, when and where, and what methods may be used. Even the best-managed fishery will have an upper limit on how much fish it can produce per year.

While reducing overfishing through better management is a critical endeavor to reduce strain on our ocean, there is also another solution that doesn’t get as much attention: alternative proteins. Plant-based and cultivated fish hold enormous potential for feeding a growing population the fish they love while easing pressure on the conventional fishing industry and, in turn, reducing harm to our oceans.

The climate benefits of alternative seafood

Conventional seafood production is caught in a precarious cycle: it's both contributing to climate change and increasingly threatened by it. Warming waters, ocean acidification, and changing ecosystems are already reducing the productivity of fisheries and aquaculture—and one study found that over 90 percent of seafood production is vulnerable to climate change. This is not a distant threat, but an urgent, near-term challenge.

By the end of this decade—recognized as the UN Decade of Ocean Science for Sustainable Development—global seafood production is expected to grow by 14 percent. But neither wild-capture fishing nor fish farming can expand at this pace without putting additional strain on ocean and freshwater ecosystems, compounding the pressures already facing a finite planet in a rapidly changing climate.

Rising ocean temperatures are already shifting the distribution of fish populations, with many species moving toward the poles and tropical waters becoming increasingly depleted. Some tropical regions are predicted to see declines of up to 40 percent in potential seafood catch by 2050. Climate change is also making seafood more dangerous to eat —for example, rates of Vibrio, a rare but often deadly bacterial infection, are rising globally.

While the research landscape for assessing the emission-related impacts of both conventional and alternative seafood is still in its infancy (a ripe area of research for the scientific and policy communities), early studies suggest that diversifying our seafood supply with plant-based and cultivated options—especially when they are produced with renewable energy—could be a transformative strategy for developing a resilient, climate-smart seafood supply chain and blue economy. One clear reason is that alternative seafood production avoids two major emissions sources in the conventional seafood supply chain: the use of fuel-intensive fishing vessels and the production and transport of aquafeed for aquaculture.

Our Building climate policy momentum for alternative seafood whitepaper offers further insights:

The biodiversity benefits of alternative seafood

Ocean and coastal environments provide essential ecosystem services that life depends on—from the oxygen we breathe, to the food we eat, to the water we drink.

But these ecosystems are under increasing pressure. A 2019 report from the Intergovernmental Platform on Biodiversity and Ecosystem Services found that humans have significantly altered two-thirds of the ocean—up from 40 percent in 2008. Biodiversity loss in marine environments is being driven by habitat destruction, overfishing, and pollution, with additional stress from climate change and ocean acidification accelerating the damage. This loss can trigger cascading consequences, including food scarcity, economic instability, and increased risk of zoonotic disease transmission.

Aquaculture—now responsible for half of the global seafood supply—is not without harm. When poorly managed, it can damage sensitive habitats such as coastal wetlands, introduce pollutants like excess feed and antibiotics, spread disease, and displace native species. These pressures, if left unchecked, erode the ocean’s productivity, resilience, and the diversity of life it supports.

Just as a diverse and sustainable food system is critical for biodiversity, biodiversity is foundational to a productive and resilient food system. Research shows that protecting and restoring biodiversity will require a major transformation of the global food system to reduce waste and increase sustainability and efficiency.

While some fisheries and aquaculture operations have improved sustainability through stronger governance and innovation, these efforts haven’t kept pace with the growing pressure on marine ecosystems. Diversifying our seafood supply with alternative proteins will be essential to reduce biodiversity loss and build long-term resilience.

As highlighted in our New Blue Foods for Biodiversity whitepaper, alternative seafood presents a strategic opportunity to diversify our food supply in ways that protect biodiversity and reduce pressure on marine ecosystems.

Key advantages of alternative seafood include:

A case study: Tuna

Tuna is fish with wide-ranging culinary applications. In some ways, this pantry staple is suffering from its own market success.

Canned tuna is the second most popular seafood product in the U.S., exceeded only by shrimp.

Americans eat about one billion pounds of canned and pouched tuna a year. Globally, more than seven million metric tons of tuna and tuna-like species are harvested yearly to meet demand. These migratory tuna species account for 20 percent of the value of all marine capture fisheries and over eight percent of all globally traded seafood.

That level of demand has put significant pressure on tuna populations and other marine creatures. In 2011, the International Union for Conservation of Nature labeled seven out of 61 known tuna species as threatened, facing a serious risk of extinction. Tuna fishing also contributes to the bycatch of vulnerable species that travel in the same waters, including sharks, turtles, and seabirds.

Today, a number of alternative protein products designed to replicate tuna already exist—and that number will only grow with further research, investment, and innovation. In 2025 alone, the field has seen several milestones:

Feast your eyes on a few plant-based based tuna products on the market that are helping to meet consumer demand more sustainably—plus a cultivated bluefin currently under development:

Impact Tuna (sushi-grade bluefin tuna made with plants)
Photo credit: Impact Food

BlueNalu's cell-cultured bluefin tuna toro
Photo credit: BlueNalu

Unlimeat tuna made from plants
Photo credit: Unlimeat

BettaF!sh tuna made from seaweed
Photo credit: BettaF!sh

Diversifying our tacklebox

A recent New York Times article on the hidden costs of our seafood system closed with a poignant suggestion: “if nothing truly good from the sea is on offer, it might be better to cook something else for dinner.” As alternative seafood continues to advance—delivering products that meet consumer expectations around taste and texture— that “something else” can come without compromise.

Scaling plant-based and cultivated seafood can help meet growing global demand while dramatically reducing the climate and biodiversity impacts of seafood production. These alternatives offer a path to ease pressure on aquatic ecosystems, rebuild overfished stocks, and cut down on bycatch and discards

Building a better food system will require a diversity of solutions. Just as the conservation community must pursue every viable path to protect ocean health, the alternative protein industry must advance multiple technology platforms to produce seafood without the animal.

Alternative seafood is the future of sustainable seafood. To scale this industry, we need bold innovators and committed champions—across climate, biodiversity, public health, and food security—who are ready to make it a global priority. An ocean of opportunity awaits.

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