Shipwrecks outperforms coral reefs in supporting marine life, study finds

Shipwrecks off the coast of Colombo serve as havens for more diverse and abundant fish than natural coral reefs, a recent study reveals.

Researchers attribute this to the complex structures of shipwrecks, which provide shelter, food, and safety for marine life, said a report published yesterday by the Mongabay, a U.S.-based non-profit conservation and environmental science news platform.

Using diver-operated video surveys, scientists recorded 2,918 fish from 20 families and 30 genera. Notably, 2,169 fish were observed on shipwrecks, compared to just 749 on coral reefs. Key shipwrecks studied included the Thermopylae Sierra, Medhufaru, and Nilgiri tugboat, popular diving sites lying at depths of 23 to 32 meters. Nearby sandstone-based coral reefs like Barracuda Reef and Anchor Point were also surveyed for comparison.

Snappers, commercially valuable fish known for aggregating in large schools, were abundant on wreck sites, highlighting their significance for local fisheries. Marine scientist Nishan Perera of Blue Resources Trust emphasized that shipwrecks act as vital underwater habitats, potentially informing the design of artificial reefs.

Shipwrecks also bolster dive tourism, which contributes $3–5 million annually to Sri Lanka’s economy. Explorer Dharshana Jayawardena, author of a book on Sri Lanka’s wrecks, suggested this figure could rise significantly. Notable wrecks like HMS Hermes, the world’s first aircraft carrier, and the Roman-era Godawaya shipwreck underscore their archaeological and ecological importance.

However, threats such as blast fishing and illegal metal salvage endanger these underwater havens. Researchers advocate for strategic use of artificial structures and further studies to protect and maximize the potential of Sri Lanka’s rich marine heritage.

The Lankan waters contain 115 known shipwrecks, with the oldest being the Godawaya wreck, dating back to the second century BCE, and they play a significant role in dive tourism, the report added.