Reopening the Strait of Hormuz: from a bioinvasion super-spreader warning to species–vessel–port prioritisation

Lorenzo Vilizzi, Aisha F. Al-Marhoun, Qusaie E. Karam, Zainab Al-Wazzan

Prolonged vessel lay-up can create an exceptional biosecurity hazard by allowing fouling assemblages to accumulate before vessels re-enter shipping networks. A recent study highlighted this risk following closure of the Strait of Hormuz and recommended pre-departure biofouling assessment, route forecasting, early detection and rapid communication. These measures address vectors and pathways, but species-targeted preparedness also requires a geographically resolved donor-region species baseline. Here, we use the recently validated Regional Organization for the Protection of the Marine Environment (ROPME) Sea Area (RSA) biosecurity baseline and integrate it with vessel-, route- and recipient-related information to support species–vessel–port prioritisation. The RSA baseline re-examined 136 species, of which 24 required reassignment or exclusion; 130 were retained and 62 added, yielding 192 species: 123 extant and 69 horizon. Thirty-nine extant species entered the very-high-priority tier, including seven benthic fouling organisms associated with shipping and ports. A watch list based on previous extant classifications would omit four of these seven. We therefore propose integrating validated donor-region occurrence with vessel exposure, route conditions, recipient susceptibility and response capacity. This framework provides an operational basis for species-targeted inspection, surveillance and rapid response and is transferable to future mass vessel lay-ups and other disruptions of maritime trade.