Houthi Attacks Force Saudi Oil Tankers to Disable Tracking and Reroute Shipments

Saudi oil tankers in the Red Sea have begun turning off their Automatic Identification System (AIS) tracking to avoid detection and attacks by Yemen's Houthi rebels. This tactic, known as "dark sailing," complicates efforts to monitor the actual volume of Saudi oil exports passing through the Red Sea, raising concerns about supply disruptions amid escalating regional conflict.

According to maritime tracking firms, all recent oil loadings at Saudi Arabia's Yanbu port occurred without continuous AIS signals, making it difficult for analysts and markets to verify shipment quantities. Estimates of daily oil loadings vary widely, with Vortexa reporting about 2.38 million barrels per day, Kpler estimating a sharp drop to 1.78 million barrels, and AXSMarine suggesting an increase to 850,000 barrels. These discrepancies highlight the challenges in assessing true export levels.

The Houthis declared a maritime blockade against Saudi Arabia on July 20 and have claimed attacks on Saudi oil tankers, port facilities in Yanbu, and other Red Sea installations. On August 9, they targeted the Aramco refinery in Jizan with a drone strike, causing a fire that was extinguished without casualties. In response to the heightened risks, Saudi Arabia has increasingly rerouted oil shipments through northern routes, including the Suez Canal and the SUMED pipeline in Egypt, which recently saw record loading volumes, mostly Saudi oil.

Shipping companies have altered routes to avoid the southern Red Sea and Bab al-Mandeb Strait, a critical chokepoint connecting the Red Sea to the Indian Ocean. Insurance premiums for vessels operating near Saudi ports and in the southern Red Sea have surged significantly due to the increased threat level. The ongoing conflict and maritime insecurity threaten to further strain global energy markets by disrupting Saudi oil exports and increasing transportation costs.