One in 10 Gulf ships cannot be reliably tracked, analyst says

• Spoofing masks ship movement near Hormuz
• Aligns with estimates of Iran’s ‘shadow fleet’
• Disabling transponder carries risk in war zone

One in every 10 vessels operating in the Gulf exhibits “anomalous” behaviour on its tracking systems, according to a shipping expert.

Spoofing, electronic interference and transponder deactivation are masking the movement of ships near the Strait of Hormuz, said Saleem Khan, chief data and analytics officer at maritime data and technology company Pole Star Global.

In a sign of how maritime visibility is degrading as the Iran war intensifies, Khan said as many as 250 of the 2,500 ships believed to be in the region are showing irregularities in their automatic identification system (AIS) signals – or vessel-tracking system.

Spoofing – in which a ship broadcasts a false position – accounts for a significant share of the activity. Khan said between 75 and 100 vessels could be engaged in the practice.

That figure broadly aligns, he said, with estimates of the Islamic Republic’s so-called “shadow fleet”, in which oil and gas tankers use deceptive practices to evade sanctions.

At a Strait of Hormuz expert panel organised by Maritime London, a not-for-profit trade association, Khan said: “Of the 2,500 vessels that are in the Gulf right now, we’ve seen about 10 percent, or 250, exhibit anomalies.” 

“I would venture that about a third of it is actual spoofing. So we’re looking at maybe 75 to 100 vessels, which is about the number of the Iranian shadow fleet.”

Khan also said vessels were disabling their AIS transponders to avoid becoming “sitting targets”.

While understandable, he warned that such action could increase the risk of misidentification in a heavily militarised environment.

“That is quite risky in a war zone, especially if you’re near a US naval base and you’re seen as potentially hostile or a threat,” he said.

“The recommendation is not to turn off your AIS – leave it on and stay in port wherever you might be in the Persian Gulf.”

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Compounding the problem is a rise in electronic jamming linked to air defence. High-powered bursts of radio-frequency interference, particularly during missile exchanges, are increasingly disrupting AIS transmissions.

The effect is not limited to shipping, Khan said. “This could impact an internet-connected toaster, oven or refrigerator, in addition to vessels at sea.” 

Addressing an audience of maritime industry leaders this week, he confirmed reports that traffic is increasing at Yanbu on Saudi Arabia’s Red Sea coast, as crude is diverted along the kingdom’s East-West Pipeline.

“We are seeing a lot more traffic into Yanbu,” he said. Saudi Aramco, the state oil giant, is moving around “4 to 5 million barrels per day” through that route.

Additional volumes are also transiting through the UAE’s Fujairah export route, which bypasses the contested waterway. But Khan stressed that both alternatives remain limited.

“The Fujairah pipeline only runs at about 1.5 million barrels per day,” he said. “Even combined, they’re not an alternative to the strait.”

Without Hormuz fully open, he warned the consequences would quickly feed through to supply. 

“We will continue to see either a slowdown in production or a complete halt. Or we’ll just see vessels waiting at docks in the Persian Gulf.”