What Can You Do With Discarded Fish Aggregation Devices

Often we bring you projects at the end of their trajectory so that you can marvel at a job well done, but sometimes we point you instead to the start of the story. Such is the case with [Brett Smith]’s investigation of discarded fish aggregation buoys, referred to as FADs. These 700-plus dollar devices are deployed in the ocean in the thousands by commercial fishing fleets, and most are not recovered. He’s looking at them from the point of view of re-using their technology in the marine conservation business.

His progress has been documented in a series of short YouTube videos, starting with an introduction that we’ve placed below the break. So far he’s gone on to a complete teardown, and then a detailed look at the PCB. Inside they have a solar charger for a bank of NiCd cells, an echo sounder, a GPS receiver, and an Iridium satellite modem allowing the device to phone home. There’s certainly plenty in there to experiment with, including a few slightly exotic parts, so keep an eye on his channel as we’re sure to see more.

These devices have never made it to Hackaday before, but we have seen an echo sounder on a surfboard.

21 thoughts on “What Can You Do With Discarded Fish Aggregation Devices

      1. Just to note, from the above linked Wikipedia page:

        ” Increasing FAD use over the past 30 years has increased the productivity of the fishing fleet, but has significant side-effects. The average FAD-caught fish is smaller and comes with relatively large bycatch raising concern about declining populations of several species of pelagic sharks. ”

        So next to the actual catching of the trgetted fish not really harmless no.

    1. They’re an improvement on what is usually used which is anything that’ll float with a load of rubbish suspended below it. Those are generally unbuoyed, unmarked and very hard to see from even quite close. They do attract fish, but also any other sea creatures drawn to the fish which may get entangled, occasionally seabirds, other floating rubbish and on occasion towed gear being used for other purposes. I ran across them in the context of seismic surveys when the colloquial name for them was “fish traps” but they used to make a good job of trapping our cables, entangling them and puncturing them releasing kerosene into the sea …

      To be honest, I doubt that the electronic version would be seen from a bridge either without something that detected their location information and presented it on a display.

      The initial video made the interesting point that it was Spanish trawlers deployed in the Seychelles that were throwing them over the wall and then just abandoning them …

      1. “The initial video made the interesting point that it was Spanish trawlers deployed in the Seychelles that were throwing them over the wall and then just abandoning them …”

        It constantly amazes me just how wasteful, thoughtless and polluting most people are, and all with the aim of making money (which translates to sheer greed in some cases, particularly where large corporations are involved). Seemingly most governments will do little if anything to combat this because of their own greed, politics, etc.

  1. I’ve never heard of or seen these despite a lot of time spent in the water or at the coast. If I’d found one, I’d definitely have pulled it apart to see what was inside. 19,000 a year at 750 dollars – that’s crazy.

  2. The cartels make good use of them as markers for their jettisoned cocaine.

    The typical tactic was to have three boats in a line operating within radio range of one another. A scout, a carrier, and a retrieval. If the scout spotted what looked like military or law enforcement of any kind in a relatively untraveled part of the ocean the carrier would dump the load with one of these FAD beacons for the retrieval boat to pick up.

    All the ones we found were activated by removing a magnet from one side. Putting the magnet back opened the switch and turned it off.

    There was brief talk of trying to use radio direction finding (RDF) to zero in on the beacons as they transmitted. However, given their prevalence and disposable nature, far too many resources would be burned up just tracking down legitimate, or lost/abandoned gear.

    1. For the enterprising narcotics thief it would be an interesting endeavor. Either you get a FAD used for fishing (that you can scrap for parts) or you get a FAD and some pricey extras.

      Honestly, just hunting for these things with DF equipment and scooping the trash (the FAD) aout of the water seems like it would be a saitsfying endeavor.

  3. You would be even more amazed if you knew how some Navy vessels are handling their disposals. Word is that towards the end of a fiscal year old furniture and electronics are being dumped in the seven seas to make space for fancy new stuff…

    1. This is/was standard procedure for refurbishing cruise ships – chuck everything overboard on route to the port. Tables, chairs, carpets, beds…

      But cruise ships are just floating consumerism at its worst so hardly surprising.

  4. Retrofitting a ton of these with LoRa modules, and having an ocean-wide, albeit low-bandwith mesh based on a store-and-forward setup, with matching transceivers on yachts/ships could be used as a supplementary service for eg. weather warnings, SOS, or even low bandwidth personal messaging, either between vessels or from vessel to shore.

    Of course, we already have satellite comms for marine use, but having something like this in addition would be pretty cool.

    I’d imagine that there may be issues with signal propagation over long distances at 400-900mhz at sea level though, but if it could be made to work well, this would be a perfect application for them.

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