Ocean biodiversity faces a spectrum of known threats, from climate shifts and acidification to widespread marine pollution. Humanity is trying to lessen these impacts, yet the sea remains vulnerable. Projections suggest that within five to ten years new hazards could emerge that reshape marine life. With this in mind, a team of international researchers led by the University of Cambridge presents a list of fifteen issues likely to influence marine ecosystems over the coming decade.
Experts identify several problems that have not yet received widespread attention but are expected to grow in importance. “Early recognition of these issues and their potential effects on marine and coastal biodiversity will allow challenges to be addressed from multiple angles,” notes James Herbert-Read, co-author of this study (Nature Ecology and Evolution).
1. Forest fires
Climate change drives more frequent forest fires, and their effects extend beyond land. The smoke and flames emit aerosols and particles containing elements such as nitrogen, phosphorus, copper, lead, and iron. Winds and rain can transport these materials across vast distances, depositing them into marine systems. For instance, the 2020 Australian bushfires triggered a massive phytoplankton bloom in Antarctica, with downstream consequences for fish and invertebrates (Nature Ecology and Evolution).
2. Shore blackout
Light is essential for coastal ecosystems to function, yet the ocean is growing darker. Warming, pollution, storms, and melting ice reduce light penetration, clouding coastal waters. In moderation, reduced light can help prevent coral and reef bleaching, but widespread, repeated dimming can impose chronic stress and lead to lasting ecological changes.
Fish and seagrass beds can be affected by shifts in light, altering growth and timing of life cycles. This dynamic has implications for coastal food webs and nutrient cycling.
Fish swimming among seagrass and other shallow habitats illustrate the visible side of this change. (Photo credit: Shutterstock)
3. Metal pollution and toxicity
Even with stringent controls, metals persist in sediments for long periods due to continual physical disturbance from storms and fishing activities. Ocean acidification increases metal solubility and toxicity, intensifying impacts on marine fauna. While not all species are equally affected, bivalves are among the groups most at risk (Nature Ecology and Evolution).
4. The equator emptied by climate migration
Rising temperatures push many species toward cooler waters at higher latitudes, while warm-water species colonize mid and low latitudes. In regions near the equator, heat-tolerant organisms dominate, leaving little room for substitutes. The ecological outcomes in these equatorial zones remain uncertain, but established communities may decline as new assemblages form, altering the biological roles within the ecosystem (Nature Ecology and Evolution).
5. Shifts in the nutritional value of fish
Climate-driven changes reduce phytoplankton production of essential fatty acids, including omega-3s. Heat stress lowers the abundance of these nutrients, triggering downstream effects on the prey relied upon by top predators and, ultimately, on human health through seafood consumption (Nature Ecology and Evolution).
Images show fish in seagrass beds and associated habitats that illustrate these shifts in nutrient dynamics (Photo credit: Roger Grace).
6. A growing market for collagen
Collagen demand rises across cosmetics, pharmaceuticals, and biomedical sectors, prompting searches for new sources. Marine organisms surface as alternatives, but researchers warn that exploiting marine collagen could undermine efforts to curb overfishing. Sponges, jellyfish, and sharks are potential sources, yet the most sustainable approach may lie in making use of byproducts from the fishing industry, thereby supporting blue and circular economy principles (Nature Ecology and Evolution).
7. Luxury seafood on the rise
Seafood markets are expanding toward luxury items, including the increasingly coveted swim bladders of certain fish, sold at extraordinary prices. Scientists warn that the pursuit of these products could drive overfishing and promote harmful methods such as extensive trawling, threatening ecosystem balance (Nature Ecology and Evolution).
8. The impact of deep-sea fishing
Concerns about global food security push nations to fish beyond traditional limits. In the mesopelagic zone, species such as small anglerfishes are being targeted for feed and fertilizer. These deep-sea dwellers play a key role in the carbon cycle, moving surface-origin carbon to depth via excretion. Their removal could disrupt a major carbon sequestration pathway (Nature Ecology and Evolution).
9. Marine lithium extraction
Growing demand for batteries, including for electric vehicles, could shift lithium extraction toward seawater pools and deep-sea environments. While concentrations in seawater are low, certain deep-sea pools are considered abundant reserves. Any extraction must weigh the potential harm to endemic, yet undiscovered, species that inhabit these areas (Nature Ecology and Evolution).
10. New marine infrastructures
Offshore wind farms and other sea-based infrastructures respond to energy, fishing, and shipping needs. The aim is to balance economic gains with space efficiency and minimized environmental impact. Yet the absence of unified environmental governance raises questions about long-term ecological effects and the ability to regulate such developments effectively (Nature Ecology and Evolution).
Offshore wind farm imagery underscores the scale of these projects (Photo credit: Shutterstock).
11. Floating sea cities
The concept of sea-based cities has gained traction since mid-century and is nearing realization in places like the Maldives. These structures offer housing stability amid rising seas, yet their foundations could facilitate invasive species spread. Designing solutions that protect native ecosystems while providing resilience remains a challenge (Nature Ecology and Evolution).
12. Green energy pollution
Switching to greener energy is essential to reduce warming, yet expanding use of electric vehicles increases battery demand. Recycling of end-of-life batteries remains inconsistent, creating risks of toxic elements entering the environment over the life cycle (Nature Ecology and Evolution).
13. Monitoring deep-sea species
Researchers understand surface movers well, but deep-dwelling species remain largely mysterious. MIT has developed an underwater positioning system called Underwater Backscatter Location that tracks elusive seabed animals with centimeter precision. Debates continue about how this technology might alter animal behavior and ecosystem dynamics (Nature Ecology and Evolution).
14. Soft robots for the sea
Soft robots, built from flexible materials inspired by living organisms, enable deeper exploration than rigid bots. They can collect samples in deep waters, yet there is a risk they could leave behind pollutants. Predators may also mistake them for prey, creating new ecological interactions (Nature Ecology and Evolution).
15. Effects of new biodegradable materials
Biodegradable polymers seem like a solution to plastic pollution, but many have not been thoroughly evaluated for toxicity or life cycle impacts. Long-term environmental effects of widespread use in products such as clothing remain unknown, and some natural microfibers may be more toxic to fish than traditional plastics (Nature Ecology and Evolution).
Notes from the study emphasize the need for careful assessment before scaling up new materials or harvesting approaches in the oceans (Nature Ecology and Evolution).