Researchers from the University of Plymouth have revealed a surprising role for sunken ships: they act as bustling underwater habitats that support a wide array of marine life. The findings, published in Marine Ecology, highlight how wrecks create stable shelters for algae, small fish, corals, and other organisms, shaping local ecosystems along coastlines. This work strengthens the case that shipwrecks can contribute to biodiversity in busy marine zones as more than just relics of the past.
Across the coastlines of the British Isles, scientists estimate there are nearly 50 thousand sunken vessels that have rested on the seabed for decades or even over a century. These wrecks appear to offer a form of refuge by reducing the impact of human activities that disturb the seabed, such as bottom trawling, and by providing surfaces for organisms to attach and communities to develop. The study notes that wrecks may serve as natural barriers that preserve delicate habitats and help to maintain ecological balance in the surrounding waters.
To understand these effects, local ship crews assisted researchers in gathering video footage of wreck sites and the nearby sea floor within a 50-meter zone, while monitoring open areas beyond 150 meters from the debris. This approach allowed scientists to compare life density and species variety directly between the sheltered zone around wrecks and more exposed, trawled regions.
The results show a striking contrast: marine life density near shipwrecks averages about 240 percent higher than in zones affected by trawling. Within a close 50-meter radius of the debris, the increase climbs to roughly 340 percent. These figures underscore the ecological value that wrecks provide, not as passive objects, but as functional components of coastal ecosystems that support complex food webs and habitat mosaics.
The study also points to the long history of bottom fishing gear usage starting in the 1800s and how this practice has reshaped marine communities and their habitats. Beyond legally protected zones at sea, protection tends to be limited to areas inaccessible to ships, which makes shipwreck sites even more important as de facto refuges. Researchers emphasize that while wrecks are not a substitute for formal protections, they contribute to marine resilience by hosting diverse life forms and supporting biological processes that benefit larger ecosystems and fisheries. The contemporary takeaways from this work are clear: wreck sites deserve consideration in marine spatial planning and conservation strategies, especially in regions facing increasing fishing pressure and habitat disturbance. This interpretation comes from the Plymouth team as part of ongoing investigations into how long-standing human activities intersect with natural marine dynamics.
In summarizing the implications, the researchers argue that protecting and monitoring shipwreck habitats could complement established conservation measures. These wrecks illustrate how artificial structures can blend with natural processes to sustain biodiversity, offering a practical example of coexistence between human activity and marine life. The study adds to a growing body of evidence that artificial reefs and wrecks can contribute to ecosystem services, including nursery grounds for fish and refuges for benthic communities. This perspective aligns with broader efforts to understand how human-built elements interact with ocean life and support healthier, more productive coastal ecosystems for generations to come. The research can inform policy discussions, management practices, and community-based stewardship initiatives that seek to balance maritime use with ecological integrity.