Perim Island odds Explode After Yemen Forces Claim the Strait

Perim Island odds ripped higher on Polymarket after Saudi-backed Yemeni government forces said they had retaken Perim, also called Mayyun, from the Houthis. The tiny volcanic island sits right in the Bab al-Mandab Strait, one of the most important shipping chokepoints on the planet. Traders now price a better-than-even chance the Houthis lose it by October 31, but the market rules are strict.

What actually happened

Asharq Al-Awsat reported that Operation "Dawn of Yemen" entered its fifth day on Friday, October 9. Military sources said the Giants Brigades and Nation Shield forces had established full control over Bab al-Mandab, the Al-Ardi military camp, coast guard observation posts, Mayyun Island and the surrounding mountains.

Asharq Al-Awsat framed the gain with a condition: if the announced control is maintained, it would mark a significant turning point on the western coast. The paper says forces had earlier seized the Kahboub Heights and kept pushing on the Al-Wazi'iyah front west of Taiz, toward Dhubab, the Al-Omari camp and eventually Mokha. MarineRadar adds that government forces also pushed toward Hodeidah, the Houthis' main Red Sea supply port, which remains contested.

A government military source told dpa, via Yemen Online, that clashes and clearing operations were still ongoing. Yemen Today quoted a source saying the island was completely free of Houthi presence after a deadline for encircled fighters expired.

The Critical Threats Iran Update for October 9 is more careful. It says government-aligned forces "reportedly" seized Perim, citing anti-Houthi Yemeni sources and geolocated footage, and that clearing of remaining Houthi pockets continued. It notes the capture of Jabal Kahbub high ground on October 8 may have enabled the push.

Timing differs by source. Most outlets put the island's capture on October 9. MarineRadar instead says the island and the nearby Ras Menhali headland changed hands over October 7 to 8. We're stating both and not picking one.

What Polymarket thinks

The Polymarket market asks whether Perim Island will no longer be under Houthi control by a set date. At 06:00 UTC on October 10, the lines looked like this:

• October 15: near 29.5%, up about 24 points in a day.
• October 31: near 56% (bid 53, ask 58.8), up about 40 points.
• November 30: near 70.5%; December 31: near 75%, with a wide 67 to 83 spread.

The event has traded about $196,000. Perim Island odds are below the headlines for a reason: the rules say an announcement or claim doesn't count without actual control, and temporary raids or landings don't qualify. If control is contested, unclear or disputed at the deadline, it resolves No.

Why traders aren't at 90%

The strait has flipped before. MarineRadar notes the Houthis completed their takeover of Yemen's Red Sea coastline last month and seized Perim at that time, and that the area has changed hands repeatedly since fighting intensified in late August. The Houthis also keep substantial missile and drone stockpiles.

Critical Threats adds a strategic caveat. Losing Perim and al-Aradi takes away positions from which the Houthis could hit shipping with artillery and tactical drones. But it doesn't stop attacks from other spots along the coast, including the Hanish Islands or areas near Mokha.

The shipping angle

MarineRadar says traffic through Bab el-Mandeb on October 8 ran slightly higher than in prior days, but still far below the pre-conflict average of more than 60 ships a day. A separate Polymarket market on the strait being effectively closed by December 31 sat near 14.5% in our snapshot. For a similar setup in the Gulf, see our Hormuz traffic odds piece.

What to do as a reader

Treat Perim Island odds as a bet on durable, verifiable control, not on the first victory post. Look for official statements from governments and militaries, plus independent confirmation, before assuming the Yes side is safe.

Short-dated lines like October 15 swing hardest on rumors. If you follow the wider conflict, our Iran ceasefire odds explainer covers the regional backdrop. Nothing here is investment advice.