Idle ships near Strait of Hormuz risk spreading invasive species

An international team of 24 marine scientists, led by UMCES and including WHOI, published a study in Biological Invasions warning of a potential 'bioinvasion super-spreader event'.

About 1,500 vessels stranded in the Persian Gulf and several hundred more in the Gulf of Oman due to the Strait of Hormuz closure since the US-Iran war began on February 28, 2026.

Prolonged anchorage allows dense biofouling—algae, barnacles, mussels and other invertebrates—to accumulate on hulls, which could spread invaders globally when trade resumes.

The Strait of Hormuz is the world's most critical maritime energy chokepoint, facilitating roughly $600 billion in energy trade annually.