Dataset Rich Content Info test
We combine tracking data from the publicly available automatic identification system (AIS) and integrate that with information acquired through vessel monitoring systems that are operated by governments and made available to us through partnerships that we secure. Both AIS and VMS combine global positioning with a transmitter to regularly broadcast vessel location.
Automatic identification system
The International Maritime Organization and other management bodies require large ships, including many commercial fishing vessels, to broadcast their position with AIS in order to avoid collisions. Each year, more than 400,000 AIS devices broadcast vessel location, identity, course and speed information. Ground stations and satellites pick up this information, making vessels trackable even in the most remote areas of the ocean.
While only two percent of the world’s roughly 2.9 million fishing vessels carry AIS, they are responsible for over half of the fishing effort that takes place more than 100 nautical miles from shore, and as much as 80 percent of the fishing that occurs on the high seas. The number of fishing vessels with AIS is increasing by 10 to 30 percent each year, making this technology more and more informative with time.
Vessel monitoring system
VMS tracks vessels in a similar way to AIS, but has historically been restricted to government regulators or other fisheries authorities. Several countries have released their VMS publically on the Global Fishing Watch map. VMS systems broadcast positions at set intervals and some systems allow operators to increase transmission frequency when needed. Some vessels broadcast both AIS and VMS so information from both systems can be combined to give a higher resolution vessel track.
We synthesize more than 30 public vessel registries each month to develop a comprehensive database of known vessel information, including identity—ship name, call sign, IMO number—size—length, tonnage, engine power—authorization status and ownership.
Vessel tracking data is critical for tracking commercial fishing activity, but monitoring AIS and VMS still leaves out a significant portion of global fishing activity. Imaging-based systems can detect vessels that have no tracking device or those whose tracking devices have been switched off to conceal their location. We are therefore working to incorporate numerous satellite imagery sources for a more complete picture of global fishing activity.