Dangerous AIS Targets? New Challenges To Safe Navigation - PassageMaker
Unregulated AIS fishing beacons are most likely illegal and pose a hazard to navigation

Interested in better understanding the navigational rules and how vessels interact? Check out our Boaters University course, Fundamentals of Seamanship: Navigational Rules. Use the promotional code PASSAGEMAKER for 20% off. 

Heading north around Cape Hatteras a few weeks back, we found ourselves facing a number of targets along our intended course - only some were more dangerous than others. That green target at top right of the image (36870200) was an American aircraft carrier performing incredibly tight turns and circles - but that wasn't the danger. Neither was the fast moving target to the left of our track (the track in black), which was the Captain Caden, a 21 meter fishing vessel out of Barnegat Bay.

A Busy Waterway, However The AIS Fish Beacons Give Me Great Fears

A Busy Waterway, However The AIS Fish Beacons Give Me Great Fears

FV Handful & Four Local AIS Beacons

FV Handful & Four Local AIS Beacons

The real danger was that tiny cluster of targets on our starboard side - the US flagged fishing vessel Handful, seen here with a cluster of AIS beacons around it (note: this image, and those that follow, were produced by replaying our voyage on our electronic nav system). The target shapes are different when in actual navigation mode). If we zoom in (at right), the picture becomes clearer - one primary AIS target, being the fishing vessel Handful itself, plus a cluster of four AIS fish net beacons floating around her. Fish net beacons, using AIS. Hmm. OK, read my lips. Say after me. This is not good....

The AIS system was devised and built as a safety system for vessels under management. It was not built as an identification system for unmanned, unpowered fish net and long line floats that do not ask questions and cannot correct their course. If the technology is used for net tracking, the targets should display with a clearly different icon or graphic on screen. But they do not. They look just like ships on screen.

The IMO (International Maritime Organisation) has published guidelines for the display of navigation related symbols on screen (read them here) and no fishing target beacons are included. The United Nations Food & Agriculture Organisation has published a draft paper (read it here) on marking of fishing gear, which acknowledges the illegal nature of AIS fishing beacons, but doesn't come down against them.

Thanks to Ben Ellison, author of the excellent PANBO marine electronics blog, I obtained the following information from a US Coast Guard website :

"18. Can I use AIS to mark nets, pots, traps, moorings, or as a race mark, etc.? There are no outright prohibitions to use AIS (i.e. AIS AtoN) as a marker (see Types of AIS and IALA Recommendation 1016 – Mobile Marine Aids to Navigation). However, it is not permissible to do so with equipment intended for use on vessels, (i.e. AIS Class A or B devices), for lifesaving (i.e. AIS SART, MOB AIS, EPIRB AIS), or with devices that are not FCC certified and licensed. See 47 CFR §§ 2.803, 2.805, 2.301, and 80.13 regarding licensing, station identity, and the prohibition to sell, market, or use radio devices that are not FCC authorized (search, Equipment Class: AIS)." It appears then that so long as these devices are FCC approved, they can be used at sea. But are they FCC approved?

So, what has gone wrong? Firstly, Chinese manufacturers have seized on an opportunity to use AIS electronic packages as fish net beacons, though without any approvals from relevant international AIS scheme managers. Secondly, U.S. fisherman keen to track their nets (at very low cost) have seized on these tools and deployed them, even though they are illegal under U.S. law (my opinion). In fact you can't buy these readily in the United States - you have to order them online through Ali-Baba or one of the foreign web supply chains.

Ova fishing buoy beacon

Ova fishing buoy beacon

Above is the Ova fishing buoy beacon, sold out of China on the internet for not much over $100 USD, waterproof to 10 meters, and it comes pre-programmed with it's own MMSI number. Wait a minute - how did that happen? An MMSI number is supposed to be a Maritime Mobile Service Identifier, a number that identifies a vessel and an owner and tracks back to the national registration of the identified vessel.

Whoever heard of MMSI numbers being issued by the factory that built the product....geez. They are supposed to be issued by the country of registration!

Another model of an AIS fishing buoy beacon.

Another model of an AIS fishing buoy beacon.

Then there are other brands and models. In fact there are so many models that there is an entire marketplace on the web where you can buy these (illegal) devices. Check out the page at this address. Many are shipped with software plus a cable that allows the user to program the MMSI number - this is completely illegal under U.S. FCC regulations.

Many fisherman reading this story will be wondering what the heck I'm complaining about. Okay, so it's illegal, but where is the harm? In fact it can be said that the fisherman are doing us a favor by identifying nets and floats that otherwise would be invisible to us at night. However, until these beacons can be identified easily on screen as floating beacons (and not ships), then I believe that some dangerous situations are being created.

Illegal AIS Fishing Beacons - The Problem

941 Prefix Is Illegal Transponder

941 Prefix Is Illegal Transponder

The image at right shows us approaching a series of illegal buoys: there are five in evidence here, though in reality their were eight AIS markers attached to the fishing lines. Of course we didn't know they were beacons since we thought it was a fleet of fishing boats ... the system doesn't provide any discrimination or guidance on screen.

Problem is, they are so low to the water that the signals also drop in and out constantly, with no consistency on the screen of the approaching vessel. It's very confusing. Further, most of these net or line arrangements have an escort vessel that keeps an eye on the harvest. Yet in this case the fisherman responsible did not even put a proper AIS transponder on the escort boat.

Flying up the gulf stream at night, we had numerous intermittent AIS targets that we could not see or correlate on radar, plus one obvious boat target on radar that did not even have an AIS transponder.

Now, please look at the fast moving target (number 211801000) heading straight into the array of illegal targets. At about 18 knots. We spoke with the officer of the watch on this ship (Northern Monument, a 300 meter container ship) and asked if he knew what these targets were..... his response is truly sobering, and scary. "I'm not sure what they are; I am so confused." He was confused enough to hold course and plow on through the target area; maybe he dragged a few illegal buoys down and destroyed them.

The issue here is that we really don't want ship captains being so confused that they ignore AIS targets in front of them and just plow on without care. Really, what is the point of a safety system that is no longer safe?

Illegal AIS Fishing Beacons - Observed Behavior

Targets Appearing Dead Ahead

Targets Appearing Dead Ahead

These little beacons have up to 5 watts of power, so in theory they should be reliably visible for some distance. But that is not the case. Because they transmit very close to water level, they tend to drop in and out on our viewing screens. And the closer we get to them, the more difficult they are to receive.

This isn't a problem for the fishermen since they already know the general area in which they are searching, however, it is a problem for other navigators. The signals can pop up at the last possible minute, right in front of you - and when you look ahead in daytime or on radar, nothing is there. Suddenly the whole AIS system reliability is thrown into question. On screen, they look like a fleet of ships, when you can see them.

In the image at right the fishing boat Sea Angel is tending the nets, however that target right in front of our bow has just popped up. We really didn't have time to avoid it, and it went past on port side about 10 meters away. 

Professional fishing friends tell me that these transponders were not actually attached to nets. Rather it was Mahi Mahi season on the coast, and the transponders were on baited long lines attracting the big Mahi fish.

At this point I need to re-state the obvious:

Two Ships On Port, Two Illegal Targets Ahead

Two Ships On Port, Two Illegal Targets Ahead

  • The AIS system was built to enhance safety for ships at sea
  • In the USA, all AIS devices must be programmed and identified by the dealer or installing technician: End users must not be able to program the MMSI number.
  • • AIS beacons are now manufactured for other applications, such as personal man overboard emergencies.
  • However, there are no industry standard (that I'm aware of) that supports AIS technology being used for tracking nets or long lines.

It is unfortunate that these illegal beacons are being purchased by fishermen and deployed in shipping lanes. The result is that ships' officers may now be less inclined to alter course when they see an AIS target in front of them. It's a massive step backward in safety for all mariners, because the illegal beacons display on screen using the same icon / graphic as a normal boat. Many of the beacons we observed were programmed with the name of the escort vessel such that they displayed a ship name and graphic. It is very confusing and likely to cause an accident at some point.

After forwarding this information to the US Coast Guard we received a very prompt response from them, as follows: "Given their use of an illegitimate MMSI number(s) and other erroneous data in their broadcast it is most likely that they are one of the illicit devices also shown on your webpage. We are well aware of the proliferation of these devices, notwithstanding ours and the FCC's best efforts to shut down outlets that have tried to sell here in the U.S. Next month we are poised to publish a Public Notice which will hopefully get the word out to their users, and heed them to cease and desist. Note, these and other Autonomous Maritime Radio Devices (AMRD) are a worldwide issue being addressed at the International Maritime Organization and International Telecommunications Union. Hopefully, in the not too distant future we will have a better paradigm for their legitimate use, beyond what is already permitted under the AIS Aids to Navigation station approval." 

So it appears the USCG is on the case, and things may improve in the future.

Last night I had dinner with a U.S. east coast professional fisherman, a friend, who also believes these beacons should not be in use. He's on his way to La Jolla (CA) this weekend for a board meeting of the Seafood Harvesters group, and will raise this issue with them. That group includes representatives of all the commercial fishing operations around the USA. Not sure what will come of that, but it's another pressure point to get things moving.

This whole situation can be rectified if the AIS system governing bodies will agree on a unique display icon/graphic for fishing beacons. That way we could sort out the dangerous targets from the smaller (less dangerous) targets. Right now it's a confusing and dangerous mess.

This article first appeared on Neil & Ley Langford's blog, Crystal Blues, it is reprinted here with permission.

Related