A recent study suggests that the blockade of the Strait of Hormuz has caused a significant number of ships to be stuck in the Gulf region. This situation could lead to a potential “super-spreader” event, with severe environmental implications in the long term. The research, released on July 22 in the journal Biological Invasions, highlights the risk of various marine organisms, such as algae, barnacles, and tunicates, attaching to idle vessels in the Persian Gulf and the Gulf of Oman, posing a major global biosecurity threat when these ships eventually resume their journeys.
Lead author Mario Tamburri, a professor at the University of Maryland Center for Environmental Science, emphasized the unprecedented nature of this biofoulic spread, stating that the current scenario presents an ideal opportunity for the widespread movement of diverse species across different regions. The study estimates that around 1,500 ships are currently stranded in the Persian Gulf, with additional vessels stuck in the Gulf of Oman due to the ongoing closure of the strait amidst the U.S.-Iran conflict.
The accumulation of organisms on ship hulls, known as biofouling, can facilitate the inadvertent spread of invasive species to ports worldwide if proper precautions are not taken, as highlighted in the paper. The extended period of inactivity for these ships, some of which have been stationary for significantly longer than usual, coupled with the inefficacy of hull coatings in preventing biofouling during prolonged idleness, further exacerbates the risk.
Tamburri and his team describe the situation as a worst-case scenario, emphasizing the potential for these ships to act as “super-spreaders” due to their numbers, close proximity, and the timing of the blockade coinciding with the onset of the growing and reproductive seasons for many organisms. Marine species adapted to the warm and saline conditions of the Persian Gulf could establish themselves in new environments, particularly as ocean temperatures continue to rise.
Efforts to clean these vessels before departure face significant challenges, as the current capacity of in-water cleaning companies falls short of the required scale, and safety concerns arise from sending workers into the water during a conflict situation. The lack of mandatory regulations around biofouling management, unlike those for ballast water treatment, further complicates the mitigation of this ecological threat.
The potential ecological impact of the spread of invasive species through biofouling is underscored by the experiences with zebra mussels in the Great Lakes, prompting increased awareness within the shipping industry and governmental bodies. The establishment of invasive species in new ecosystems could lead to detrimental consequences, as these organisms may out-compete native species, disrupting local biodiversity and ecosystems.
In conclusion, the blockade of the Strait of Hormuz has inadvertently created a high-risk scenario for the global spread of invasive species through biofouling on stranded vessels. The situation serves as a stark reminder of the interconnectedness of geopolitical events and ecological repercussions, highlighting the urgent need for proactive measures to address the potential ecological threats posed by such events.