Read our Privacy noticeThe economic ramifications of the closure of the Strait of Hormuz are much discussed. As the strait reopens, these ships may spread these organisms to ports they visit, potentially causing an international biosecurity “super-spreader” event. But the closure of the Strait of Hormuz is not the first time shipping disruptions have resulted in significant biofouling on idle vessels. For example, Biosecurity New Zealand was able to screen and take action when cruise ships were laid up during the COVID pandemic. We recommend the following actions to manage the biofouling risk for vessels arriving from the Strait of Hormuz region.