Going Dark: When Vessels Turn Off AIS Broadcasts

Something we hear often about tracking vessels with Automatic Identification Signals (AIS) is that transponders can be turned off. Fishers that don’t want to be caught doing something illegal or questionable will simply “go dark.” Read more

Spoofing: One Identity Shared by Multiple Vessels

The satellite-based Automatic Identification System (AIS) that we use for tracking vessels is a radio transmission system in which a ship sends a coded message that can be picked up by satellite and land-based receivers. The code includes Read more

Scientists develop precise methods to identify and measure three very different types of fishing activity

On dry land, ecologists and conservationists can map our human footprints on the landscape. We can see deforestation, mountaintop removal, river damming and development, and it is relatively easy to recognize our impacts on an ecosystem and the plants and animals that live there. Read more

What Does Five Billion Look Like?

Every day we download more than 20 million data points, giving us the positions of the about two hundred thousand vessels in the world. To see where these vessels traveled in 2015, I plotted their positions to create the map you see above. This map shows all vessels carrying AIS, and not just fishing vessels, and is created from about five billion data points. Click on the image to enlarge. Read more

Reading Tracks on the Water: A Team Effort for Humans and Machines

When it looks like spaghetti, it may be fishing. That’s one of the first lessons students learn when they’re working with Kristina Boerder, one of our academic partners from Dalhousie University in Halifax, Nova Scotia. Of course, she’s not teaching them about pasta. She’s teaching them about the movement patterns of ships at sea. The students are helping Kristina classify the tracks of ocean-going vessels recorded from satellite signals. Read more