**Houthi territorial gains along Yemen’s Red Sea coast in mid-September 2026, including the capture of Mokha port, Perim (Mayun) Island, and surrounding areas, have given the group direct oversight of Bab el-Mandeb shipping lanes.** This has driven sharp drops in vessel transits—often halving daily crossings to the 15–25 range on many days—prompting widespread rerouting around the Cape of Good Hope, elevated war-risk insurance, and selective targeting of Saudi-linked tankers. Traffic has not reached zero, however, with non-targeted vessels and some bulk/tanker movements continuing amid no formal closure declaration by maritime authorities. Yemeni government and Saudi-backed counteroffensives reported in early October, alongside UN warnings of ongoing volatility, introduce uncertainty. Trader consensus on Polymarket reflects these developments through moderate implied probabilities of effective closure (defined via IMF PortWatch 7-day averages ≤10 arrivals) by year-end, balanced against persistent though reduced flows and potential for further escalation or stabilization.