By Mike Hillers
Successful fishing trips are the result of tools and intuition and how these system components manifest themselves in the brains of the fishermen to become decisions and commands from the wheelhouse.
Delving into the brains of fishermen might be best left alone, or to the professionals, but tools are fun, plentiful and very varied. Selecting tools to form ‘Fishing Systems’ that can provide the information and data to influence decision making is important. The right tools will both ease stress and increase the efficiency of all fishing operations.
Many decisions are made on a macro level; When to fish and where to fish are the usually the result of regulation, weather or geography. Within the confines of these parameters however the fisherman takes control. It is unheard of for a fisherman to rely on a compass and a lead line these days even though those tools could have been considered a “system” back in the day.
Today efficiency requires a vast array of tools to be, and remain, competitive. And there are a lot of tools to pick from.
What is needed from an electronics perspective? GPS is a necessity as well as a radar and an echosounder. These will answer the questions of vessel location and vessel location in relation to surface and underwater objects and obstacles. These are basic for any professional mariner, but an advanced ‘Fishing System’ requires much more.
A sonar is has not always been considered a necessity, but these days it is. The sonar is the tool that will provide the first and best indication of where the fish are located, well in advance of the vessel. A modern sonar is a tool that will indicate both, presence or absence, as well as having the resolution to show fish behavior.
Observing fish behavior will, in the brain of a fisherman, translate to an assumption of species. This is important to note because as much as AI is in the news and algorithms are deciding what information we “need” or should have, the mind of a fisherman is still in charge and making the decisions on all fishing vessels I have been on. Any idea of species will help the fisherman to target, or if the determination is that the fish are a by-catch species, to avoid, the detected fish.
Avoidance is increasingly important as catching unwanted species or unwanted sized fish is a waste of time or worse.
Once the fish are located and as much information is gleaned from the sonar as possible, the vessel should be over the fish and the echosounder is in play. A modern echosounder will have the resolution and the processing capability to give you fish size, biomass and some indication of the bottom type or hardness. This is the point where the fisherman is lining up the targets with the trawl to catch, and he’s using tools like a current indicator and trawl positioning system. The current indicator lets the fisherman make a judgement about the direction the fish will move between seeing them on the echosounder and the trawl opening. The trawl positioning system allows the fisherman to position the trawl to, ideally, intersect with the fish.
Trawl parameters like door spread, door roll, door height off the bottom etc. are also being watched from the wheelhouse, as the trawl efficiency is another key to success. Trawls are technical tools in their own right and as such tuning and finesse improve efficiency. Information is needed to ascertain performance.
With the fish now entering the trawl, the fisherman is still making decisions. Mainly, are these the right fish? By-catch is a large consideration. Some species of rock fish, caught in volume, have the potential to shut down the hake fishery. Salmon in the Bering Sea also need to be avoided, and in many fisheries, fish value varies by size.
In the past two decades a tremendous amount of individual and collaborative effort has gone into excluding fish after they have passed the plane of the trawl opening. This effort has been the result of good stewardship and government regulations. Happily, unlike some government regulation, including, for example, the southern shrimp fishery, there was initially no equipment mandate, just a mandate on the industry to limit the total amount of by-catch. This stimulated innovation and a free flow of ideas. Flaps, excluders, vents, openings and grids have all been tried with varying degrees of success.
One thing that was needed in all these trials is information, ideally, visual information.
Cameras are the answer.
Originally, recording cameras were used to see the result of the excluder or how the flap functioned during the tow. Did the flap work? Did slowing down allow the weighted flap to drop? This was all after the fact but none-the-less valuable. The need for live, real time cameras became clear.
The result of having real time video to actually see what happens and when, leads to the inevitable result: I can see, now I want to do! This is a revolutionary advancement and so far, has led to the possibility of opening a flap to selectively or entirely release non targeted fish back into the sea! The next decade will see many advances in ‘Fishing Systems’ as a result of the current systems.
Key to most of these processes is information resolution. “Seeing” the fish acoustically on the sonar, echosounder, trawleye and the trawl sonar in high resolution gives the fisherman the ability to make species determinations, particularly if fish behavior is detectable. Knowing where your gear is and that it is performing is vital. Lastly being able to control and adjust gear on the fly is the future.
While I am sure efforts are being made with AI to ease decision making, currently all this information is processed in the brain of the fisherman, to result in the fish we all need and enjoy.
Michael Hillers has been with Simrad Fisheries since 1984 and specializes in maintaining the link between the fishermen and the engineering and development teams at the various Kongsberg factories that design and manufacture the fishing acoustics.