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Traffic in critical oil chokepoint collapses after Iran conflict erupts
Fewer than 100 ships have traversed the Strait of Hormuz since March began, a 95 % drop from pre-war daily averages, according to shipping data reviewed by BBC Verify.
Pre-war volumes and current figures
Before hostilities broke out on 28 February, approximately 138 vessels passed through the strait daily, carrying one-fifth of the world's oil supply. This month, only 99 ships have completed the crossing-an average of five to six per day.
National affiliations of recent transits
Analysis reveals that roughly one-third of the vessels that have sailed through the strait since 1 March are linked to Iran. Fourteen flew the Iranian flag, while others faced sanctions over suspected ties to Tehran's oil trade. Nine additional ships were owned by companies registered in China, and six listed India as their destination. Several Greek-owned vessels also docked at Iranian ports during the period.
Altered routes and Iranian influence
Tracking data shows that some ships are now hugging the Iranian coastline instead of using the central international channel. A Pakistan-flagged oil tanker, for instance, sailed close to Iran's territorial waters on 15 March. Bradley Martin, a senior researcher at the RAND Corporation, suggested the vessel may have been following Iranian directives, possibly to avoid mines or to remain identifiable to Iranian authorities.
Michelle Wiese Bockmann of Windward Maritime Analytics interprets the rerouting as a deliberate strategy by Tehran: "Iran is effectively closing and controlling the strait through the threat of attack and the fear of mining. Ships are forced to navigate within Iran's territorial waters and comply with its maritime rules."
Attacks and human toll
Since the conflict began, BBC Verify has confirmed attacks on 20 commercial vessels off the Iranian coast. On 11 March, the Thai-flagged bulk carrier Mayuree Naree was struck by two projectiles while transiting the strait. Three of the 23 crew members are still missing, believed trapped in the engine room. The ship's owners reported that the surviving crew were "traumatised" by the explosions.
The same day, the Greek-owned Star Gwyneth and the US-owned MT Safesea Vishnu were also targeted. One crew member died when the Safesea Vishnu was hit while anchored off Iraq; all 28 crew jumped overboard to escape the burning vessel. The ship's owner, S V Anchan, stated, "These men and women are not soldiers; they are professionals who keep global trade moving."
Tactical challenges and evasion tactics
Arun Dawson of King's College London's Freeman Air and Space Institute highlighted the difficulties faced by minesweepers operating under simultaneous air and surface threats. Iran's geography further complicates matters: the strait's narrow, shallow waters and mountainous coastline allow elevated attacks that reduce ships' reaction time.
In response, many vessels are switching off their Automatic Identification System (AIS) transponders to avoid detection. Dimitris Ampatzidis of Kpler noted that most ships now cross "with their eyes off," disappearing from tracking maps as they enter the Gulf of Oman and reappearing hours or days later. While this tactic conceals their position, it also hampers efforts by firms like Kpler to monitor maritime traffic.
Verification methods
Ampatzidis explained that Kpler validates movements through manual verification and satellite imagery, ensuring data accuracy despite the lack of real-time AIS signals.
