Ships stranded in Gulf pose global threat to biodiversity, warn scientists

By the Editorial Team · Thursday, July 30, 2026

Over 1,500 commercial ships immobilized in the Strait of Hormuz since February have become heavily colonized by marine organisms, raising fears of a global spread of invasive species once shipping resumes. Scientists warn this prolonged stagnation could lead to widespread ecological disruptions and urge stringent inspections and monitoring to prevent environmental and economic damage.

The closure of the Strait of Hormuz since late February has raised concerns among scientists about a significant threat to global marine biodiversity. More than 1,500 commercial vessels have been immobilized in the Gulf due to the ongoing conflict between the United States, Israel, and Iran, creating conditions that could facilitate the spread of invasive marine species worldwide once shipping resumes.

An international team of marine biologists highlighted that the prolonged inactivity of these ships has allowed diverse marine organisms—including microbes, algae, barnacles, and other invertebrates—to colonize the vessels’ hulls. Typically, ships remain anchored for only a few days, limiting the growth of such biofouling communities. However, the extended delays caused by the strategic waterway’s closure have resulted in dense and well-established assemblages of marine life on submerged surfaces.

Lead author of the study, Professor Mario Tamburri from the University of Maryland Center for Environmental Science, described the situation as a “perfect storm” and a potential “bio-invasion super-spreader event.” He warned that once the vessels begin moving again, these organisms could be transported across the world’s oceans, posing a risk of introducing invasive species to new environments. Such invasions could disrupt native ecosystems, cause the local extinction of species, spread diseases, and have substantial economic impacts.

The Gulf of Hormuz is already known as a hotspot for marine invasions, with prior research documenting numerous non-native species arriving primarily through maritime traffic. The region’s extreme environmental conditions — high temperatures and salinity — contribute to the resilience of these organisms, making them particularly robust invaders capable of surviving and thriving in other warm, saline locations such as India and Singapore.

The study also emphasized that the risk is not limited to organisms attached to the hulls but extends to larvae released into the water and pathogens residing in biofouling communities and ballast water. These factors could enable rapid and widespread dispersal through the global maritime network once restrictions ease.

Tamburri urged governments and shipping operators to implement thorough inspections and cleaning protocols for vessels before they depart the Gulf and to strengthen invasive species monitoring at ports expected to receive these ships. He compared the necessary response to managing infectious diseases, stressing the importance of early detection and rapid intervention to minimize ecological and economic damage.

“Prevention before you move around is really important,” Tamburri said, stressing the need for preparedness and immediate management should invasive species be detected. The findings underscore the intersection of geopolitical events and unforeseen environmental risks, calling for coordinated international efforts to address the potential global impact on marine ecosystems.

This article was reported by synthesizing coverage from multiple independent news outlets to present a balanced, unbiased account. Read about our editorial standards. Spotted an error? Let us know.