Strait Transit Monitor
Twelve chokepoints, watched weekly against their 2024-25 baseline, with a live AIS picture of each. Every strait has its own page.
Live watch
Pick a strait. The Baltic is a full snapshot (Digitraffic); all other straits share one live stream (aisstream.io) that starts listening the moment the page opens — the picture is already building while you read this, and your last visit's picture is kept warm locally.
Why some straits run dark
Live AIS on this page comes from shore receivers run by volunteers. Where the coast is a war zone, jammed, or simply without hobbyists — Bab el-Mandeb, Hormuz, Kerch, Panama's approaches — there is close to nothing to receive, and ships themselves often switch off. We benchmarked it: minutes of listening, near-zero vessels. That is not a broken map; it is what the open, terrestrial layer of AIS actually sees.
What the market does about it
Underwriters and traders buy the view from orbit: satellite-AIS constellations (Spire, exactEarth, Kpler and others) hear those same waters from above, at several thousand euros a year per seat. The gap between this page and their screens is, quite literally, the price of marine intelligence — and one reason war-risk premiums move faster than public data.
How we read the dark
Absence is a signal. The weekly transit counts below (IMF PortWatch, satellite-derived) still count every passage through the dark straits, and the AIS integrity watch tracks the jamming and dark gaps themselves, zone by zone.
Weekly transits
Vessel transit calls per week, all types, last 27 weeks. Real data from IMF PortWatch, updated weekly. Build your own view in the data lab.