Two-thirds of oil tankers ‘going dark’ through Hormuz Strait
Nearly two-thirds of oil tankers leaving the Strait of Hormuz now disable tracking systems to evade detection, up from 37 percent earlier this year, as shadow fleet tactics become standard practice.
As New York Post reports, shipping analytics firm Vortexa documented a dramatic shift in vessel behavior through the critical waterway, with 65 percent of outbound tankers using shadow fleet methods by May—a sharp increase from just 37 percent during the first month of the conflict.
Between March 1 and May 19, a total of 895 ships crossed the passage, according to maritime data company Kpler. However, only a handful of vessels are officially reported transiting the strait each day, suggesting dozens more are slipping through undetected.
The concealment technique involves switching off Automatic Identification Systems before and after transiting the strait—a method previously pioneered by Iran’s shadow fleet to transport sanctioned oil through the Strait of Hormuz.
Vortexa warned that the trend indicates AIS-off behavior is evolving into standard operating procedure rather than an emergency measure.
The firm noted that Iranian-linked vessels established the blueprint during the early crisis phase, but non-sanctioned Gulf tonnage is now increasingly adopting identical methods and beginning to dominate them in volume terms.
Multiple Routes, Uncertain Paths
Due to the nature of going dark, the precise routes oil tankers are using to circumvent trouble in the Strait of Hormuz remain unclear.
Some vessels are reportedly accepting Iran’s offer to pay tolls reaching up to two million dollars for guided safe passage through the strait, which is believed to be mined and within striking distance of Tehran’s drones and fast-attack vessels.
Ships associated with Iran, China, India, Pakistan and Japan have utilized this arrangement to move their cargo, with Iran claiming dozens of vessels have transited under its supervision in recent days.
US Blockade and Alternative Routes
Tankers departing Iranian ports face potential interception from the American blockade along the Gulf of Oman. US Central Command had intercepted 133 ships as of Thursday.
Other vessels have chosen routes closer to Oman’s coastline, likely with US Navy support. Central Command recently highlighted assisting approximately 70 ships in crossing over the past three weeks.
Oil Output Declining
Despite the apparent surge in vessels attempting to sneak through the strategic waterway, Middle Eastern oil exports remain suppressed, with larger declines recorded in recent weeks.
Average oil losses peaked at around 500,000 barrels per day during the first month of the conflict, but starting in May the depletion rate accelerated to 710,000 barrels per day, according to Reuters.
With information from New York Post
