Idle Gulf vessels could become global conduits for invasive marine species

Scientists have highlighted a looming biosecurity risk stemming from the large number of ships immobilized in the Persian Gulf and Gulf of Oman after the Strait of Hormuz was shut down. About 1,500 vessels in the Persian Gulf and several hundred in the Gulf of Oman have been stationary far longer than normal, allowing organisms such as algae, barnacles and tunicates to colonize their hulls. Lead author Mario Tamburri describes the situation as a "worst-case scenario" that could turn the fleet into a global "super-spreader" of invasive species once the vessels sail again.

Cleaning the ships is hampered by limited in-water cleaning capacity and safety concerns in a conflict zone. The study points out that biofouling has been less regulated than ballast-water transfer, despite its ability to introduce species that may outcompete native marine life. Industry groups and scientists stress that once established, such invasions are costly and hard to eradicate, potentially reshaping marine ecosystems far beyond the Middle East.