Data Help

Data Help 2017-12-19T14:51:23+00:00

Understanding the Data

AIS for Safety and Tracking: A Brief History

The maritime Automatic Identification System (AIS) is a radio communications system by which vessels continuously broadcast their identity and position over public airwaves using unencrypted VHS radio signals. When it was developed almost 20 years [...]

86,490 Points on a Map: All Potential Transshipments

5 years, over 86,000 potential transshipments In early 2017, we released an original report based on analysis of our data that revealed remarkable new insights about what goes on between fishing vessels at [...]

Making the Cut–Creating Our List of Fishing Vessels

This post has been adapted from “Updated Vessel Lists 0.2”  which appeared on our Data Blog for researchers and software engineers by David Kroodsma. Automating the process of identifying all industrial-scale fishing activity in near-real [...]

Identifying Transshipment From the Data

When two ships meet to transfer goods, it is called transshipment. In the fisheries industry, it is sometimes legal in ports, but usually illegal out at sea where the practice can’t be monitored. [You can [...]

What Does an AIS Message Look Like Anyway?

Automatic Identification System (AIS) messages are transmitted over radio waves. The system was designed, in part, so that vessels could “see” the positions of nearby ships on a monitor and avoid collisions. These radio signals are [...]

Where are the Whalers?

Last week, a visitor to our site asked if Global Fishing Watch can be used to track whaling ships. The short answer is yes, sometimes. At the moment, our machine learning algorithms are being designed [...]

Teaching Machines to Tell Us About Fishing

None of what we’re doing at Global Fishing Watch would be possible without the advancements in computing power that have occurred in recent years. The volume of data we work with would have been overwhelming [...]

What Ports Can Tell Us

Ports provide an important source of information to help us combat Illegal fishing and understand the science and economics of global fisheries. “They serve as the interface between land and sea for fishing vessels,” says [...]

Characterizing Gaps in the Data

Just a few years ago the very idea of collecting billions of radio signals from ocean-going vessels all around the world and creating a global map of their activity in near-real time would have been [...]

When Vessels Report False Locations

Occasionally, the AIS messages transmitted from a ship provide a location that makes no sense, say, in the middle of the Antarctic or over a mountain range. In such cases, either the AIS transponder has [...]

Frequently Asked Questions

Is Google paying for Indonesia’s VMS data? 2017-12-28T14:58:01+00:00

Google does not receive the VMS data. The VMS data is shared with Global Fishing Watch, Inc. which is an independent, not-for-profit company supported exclusively by philanthropic donations. Google does not pay for the data and Google does not get to use the data.

Global Fishing Watch does not pay for the VMS data, and GFW does not sell the data to anyone. All the services that GFW provides to the public and privately to the KKP are provided for free through the generosity of the Walton and Packard foundations as well as the other GFW funders.

Google does provide support for GFW by donating technology services, such as cloud computing and machine learning resources. Google does not receive any money from Global Fishing Watch.

Why isn’t the US sharing VMS data? 2017-12-28T14:58:01+00:00

The United States does not publicly share VMS data as a matter of policy. Global Fishing Watch and many other organizations are advocating for all countries, including the United States, to share more of their fisheries data publicly, and we will be happy to publish VMS data from the US whenever the government is willing to release it. The US does require all fishing vessels over 65 feet in length to use AIS, so many large commercial fishing vessels in the US are already publicly trackable.

Are there concerns about Indonesia sharing their VMS data? 2017-12-28T14:58:01+00:00

No matter what the industry, increasing transparency is always met with some anxiety from some corners. These are the concerns we’ve heard:

  • Sharing VMS is an invasion of privacy and it reveals fishing grounds to competitors. Larger vessels fishing in Indonesia are already required to reveal this information by carrying publicly broadcast Automatic Identification Systems (AIS). In addition, vessels fishing in other countries, such as the European Union, are already operating under this level of transparency.
  • Won’t sharing VMS simply force bad guys to turn off their VMS, undermining those who play by the rules and creating unfair competition? On the contrary, turning off VMS will raise suspicion among authorities and draw attention to illegal activity.
Does sharing VMS data spill Indonesian state secrets? 2017-12-28T14:58:01+00:00

No. In addition to limiting the information available on the public platform, extracting all sensitive data, we publish VMS and AIS data on a 72 hour delay. What we publish in Global Fishing Watch approximates the vessel information already being shared by the European Union and some other countries.

Why is transparency important to Indonesians? 2017-12-28T14:58:01+00:00

Illegal and unreported fishing has been a problem in Indonesian waters, as it is in many places around the world. Fishing vessels take catch without permits or take more than quotas allowed. Minister Susi is especially concerned about the impact of transshipment in her waters. Transshipment is the practice of transferring catch from one vessel to another, usually to a large refrigerated cargo ship that can collect catch from many vessels before taking it to port, sometimes halfway around the world. The concern for Susi is that fishing vessels are catching fish in Indonesian waters and transshipping it on the high seas, essentially stealing Indonesian fish. In addition, by offloading catch to another vessel, a boat may appear to have not met their quota, so they can continue fishing. They not only steal fish, but they avoid quotas and taxes on what they catch.

How does Indonesia benefit from sharing VMS data? 2017-12-28T14:58:01+00:00

Foreign vessel owners and operators will know that fishing in Indonesian waters means operating in an environment where it is harder to undermine effective management and oversight.

By establishing a high standard for transparent operation, the government can easily justify strong transparency requirements for foreign vessels and operators, because the same rules are applied to domestic operators.

In addition to public sharing, the Indonesian ministry of fisheries is gaining insight into their VMS data through working with Global Fishing Watch. Our analysts are assisting them in developing new ways to use their data for improved vessel monitoring and enforcement.

By being the first to share its VMS data, Indonesia is a leader on the world stage, encouraging other nations to embrace transparency and allowing Indonesia to better monitor the vessels of other countries.

What other countries operate with similar transparency or share similar data? 2017-12-28T14:58:01+00:00

With the sharing of VMS data, Indonesia now joins a larger community of nations that have demonstrated the value and success of sharing fishing vessel time-location data as part of transparency efforts.

Since 2009, countries in the European Union have exhibited the same level of transparency. They require vessels of 15 meters (49 feet) and longer to carry publicly broadcast Automatic Identification Systems (AIS). Indonesia’s AIS requirements are not as stringent, but the VMS requirements are, requiring VMS on fishing vessels with a capacity of more than 30 Gross Tons, which averages about 16 meters (52 ft) in length. So, opening of VMS data brings Indonesia closer to a level of transparency that already exists in Europe.

It’s worth noting that nearly all of Norway’s fishing vessels broadcast AIS, and the Global Fishing Watch map currently displays more than 99 percent of the AIS-broadcasting vessels around the world.

Is Indonesia the first country to publicly share VMS data? 2017-12-28T14:58:01+00:00

Indonesia is the first country we know of to share VMS publicly. Peru has committed to sharing their VMS data next, and Global Fishing Watch is in discussion with other countries now. We are prepared to work with any nations interested in publishing their VMS data in order to make commercial fishing activity more transparent to the world.

Won’t this tip off the fishing industry to where all the fish are? 2017-12-28T14:58:26+00:00

No. Commercial fishing fleets are already using sophisticated technology such as helicopters, tracking beacons, fish-finding sonar, and even fish forecasts based on satellite data to find and catch fish. Global Fishing Watch shows where fishing activity has apparently occurred; it doesn’t predict where fish are likely to be in the future. The 72-hour time lag also limits the use of Global Fishing Watch as a “fish tracking” tool.

Is monitoring AIS signals an invasion of trade secrets privacy? 2017-12-28T14:58:26+00:00

No. Monitoring a vessel activity through satellite AIS is already a well-established practice in the shipping, insurance and commodities industries, and AIS data is already publicly available. AIS was designed to be an open, public communications tool. Vessels that use AIS are intentionally making themselves trackable to everyone around them. Global Fishing Watch shows apparent commercial resource extraction that takes place on the open ocean, not on private property. Our fisheries are a common resource, whether on the high seas that belong to everyone or in the sovereign waters of individual nations.

Do “pirate” fishing vessels that engage in Illegal, Unreported and Unregulated (IUU) fishing even use AIS? 2017-12-28T14:58:26+00:00

Although not all of them do, we have seen vessels broadcasting AIS that appear to be fishing illegally.

Are all vessels required to use AIS? 2017-12-28T14:58:26+00:00

No, but many of the largest vessels that catch a disproportionately large amount of the fish are required to do so by the IMO. In addition, many countries and intergovernmental agencies such as Regional Fisheries Management Organizations (RFMOs) are creating AIS requirements within their waters, so we expect an increase in AIS use in the coming years. For example, as of May 31, 2014, all European Union flagged fishing vessels over 15 meters in length are required to be equipped with AIS, and as of March 1, 2016, all commercial U.S. flagged fishing vessels over 65 feet in length are required to be equipped with AIS.

Can’t vessels just broadcast a false location in their AIS signals? 2017-12-28T14:58:26+00:00

We have seen vessel tracks that appear in impossible places such as the Himalayan Mountains or over Antarctica. We can’t say for sure whether the AIS has been tampered with or is faulty, but the errors have followed regular patterns—varying from a vessel’s true location by a constant amount, or flipping a coordinate from the Southern Hemisphere to the Northern Hemisphere, for example. Once we identify the patterns, we can often correct apparently false locations.

Can’t fishing vessels turn off their AIS? 2017-12-28T14:58:26+00:00

Yes – and Global Fishing Watch can help detect when this appears to occur. We can see when a vessel appears to turn off its AIS, and we can share that information publicly. We can also flag instances where ships disappear or appear suddenly, jump 1,000 miles at once, or appear to fish on land. AIS was primarily designed as a safety mechanism to help avoid collisions at sea, so turning off AIS can put a vessel and its crew at risk of being hit by another ship.

I’m a government or data aggregator. Can I add my data to Global Fishing Watch? 2017-12-28T14:58:26+00:00

Many countries have their own AIS or VMS data that is not currently part of our feed. Global Fishing Watch seeks to build the most comprehensive public map of fishing effort possible and are happy to discuss ingesting new data sources. Indonesia, one of the largest VMS systems in the world, has been sharing their VMS data for inclusion in Global Fishing Watch and collaborating with us to better understand fishing effort in the region and provide new tools to their fishery management, licensure, and research team. Please contact us at if interested.

Is coverage equal all over the world? 2017-12-28T14:58:26+00:00

There are some regions of the world that have better coverage than others. Variation in coverage results from the presence or absence of a satellite flying overhead at any given time, reception from terrestrial receivers in the area, vessel densities (which can cause signal interference), and whether or not vessels are transmitting. Overall, coverage continues to improve with the continual deployment of more satellites and with 2017 having substantially better coverage than 2012 due to satellite increases and changes in AIS usage mandates.

Why are vessel names sometimes garbled or blank? 2017-12-28T14:58:26+00:00

Vessel names are taken directly from the AIS message a vessel broadcasts. Transmitters sometimes have errors or are not always properly configured. In some cases, we are able to match vessels to fishing registries and will use the name from there.