Ropeless Fishing? Charting a new course to sustainable fishing

Ropeless Fishing. Certainly, those two words don’t belong next to one another, right? Well, I’m glad you’re wrong. Australia started it, Canada followed suite, New Zealand wanted a piece of the action, and now the United States is interested. Fishers in these countries (and more) have begun one of the most significant changes in the age-old fishing profession. Lobster traps themselves were first invented and used in 1808 by Ebenezer Thorndike of Swampscott, Massachusetts (Hogan). Before then the use of rope has been pretty consistent in all fishing practices since, well since the dawn of fishing, in-fact, it’s the very essence of why fishing works. So why are some fishers choosing to abandon the “life line” of fishing?

Dave Casoni (left) is the first American fisher to pilot test electronic Ropeless Fishing with real gear in a fishery setting.

It originates with lobster and crab fishing gear. There are three variables that lobster or crab fishers’ gear faces on a daily basis. First, from a conservation stand-point, static or fixed lobster and crab gear is quite troublesome. The International Whaling commission suggests up-to 300,000 whales and dolphins are entangled and killed annually in commercial fishing gear, with a vast majority coming from lobster and crab fishing gear (Latest News). That doesn’t even include the animals who manage to survive yet will still face life-long damage and injuries. On top of that, several organizations exist solely to disentangle marine life who have become trapped, which in some cases leads to human tragedy in the process of trying to free them. Joe Howlett lost his life while dis-entangling a critically endangered North Atlantic Right Whale, which was caught in commercial lobster fishing gear (Donkin). While other species like sea turtles are even worse off, with around 83,300 entanglements annually (New Study).

“Joe Howlett uses a cutting tool to free a whale from fishing gear on a 2016 rescue with the Campobello Whale Rescue Team. (Canadian Whale Institute/New England Aquarium)”

Fortunately, this weeks blog isn’t a doom and gloom piece, but before I can talk more about how this issue can be solved, I have to mention a few other complications that fishers may face from using "traditional" gear. Human activity is another contributor. Ship strikes, whether by large container vessels simply too big to avoid hitting lines, other fishers, or even recreational boaters cause millions of dollars in loss value and revenue per year. Some locations off the Eastern Coast of North America have such high gear densities that even small recreational boats can’t help but accidentally cut buoy lines by hitting them.

Real gear density of lobster fishing gear off the coast of Maine. Picture by: Andrew Malone

Finally, weather plays a large part as well. Storms and strong currents can move gear due to dragging on the floating rope and buoy. Weather can also pull buoys underwater for long durations and permeant damage gear due to “tumbling”, when gear is sent cascading on the sea-floor again due to drag. Even if damage isn’t done, weather has proven to waste time with fishers searching for gear that isn’t there, thus increasing pollution and costing fishers their valuable time. Fishers are also in particular danger if they wish to move their gear out of the water before a big storm. These three problems are what Ropeless Fishing tries to address. The overall concept is pretty simple, and has been around since the 1980’s. If we can remove or limit the presence of vertical ropes and buoys in the water column, then none of these problems should occur. Yet, we still need the rope and buoy, at some point in the process, to retrieve the gear. Therefore, fishers can pack their rope into what is known as a release bag. This bag is then submerged either on or near the trap or trawl (multiple traps on one line). The single opening of the bag on the top is held shut often times with a cord or rope simply placed around the top, with a metal “holding cage” known as a retainer over the entrance. The question then becomes, how does the bag open? That’s where the big question lies. Back in the 1980’s fishers in New South Wales Australia first explored this question using a “galvanic release” mechanism. By placing two dissimilar metals next to one another in salt water, one metal would corrode at a predictable rate according to its width. Thus, fishers could use specific widths and have some certainty about when a trap might pop-up.

Galvanic release of varying sizes for pre-determined release intervals (left). Galvanic release concept (right).

Yet, the galvanic release still posed some problems. After some time, the release would snap and the buoys would float to the surface, regardless if the fisher was present or not. This meant protection from storms and potential marine mammal entanglements still posed a problem, albeit a slightly reduced one. Now enters electronic Ropeless Fishing. The same principal with the release bag applies, except the release mechanism is completely “on-call”. This means the buoys will only surface at the exact moment a fisher tells them to. The most common way this is done works through “pinging” some kind of release echanism with “Sonar”, or underwater sound signals; much the same way a bat makes clicks to gather information about its surroundings. A fisher can do this with gear on-board his boat called a transducer. Over the last year or so, this method of Ropeless Fishing has garnered a lot of attention. Canada and the United States have notably become interested due to the critically endangered North Atlantic Right Whale, which faces possible functional extinction (can no longer recover it’s population) because of commercial lobster and crab gear entanglements in addition to ship strikes. So even in the face of tremendous pressure, the fishing community, researchers, policy makers, and private industry are gearing towards solutions which serve both our coastal communities and especially marine life.

Donkin, K. (2017, September 19). Death of a whale rescuer: The untold story | CBC News. Retrieved January 29, 2019, from https://www.cbc.ca/news/canada/newbrunswick/ campobello-whale-rescue-funding-1.4287869

Hogan, M. (2018, March 21). How to Use a Lobster Trap. Retrieved January 29, 2019, from https://traveltips.usatoday.com/use-lobster-trap-13914.html

Latest news from entanglement response teams around the world:. (n.d.). Retrieved January 29, 2019, from https://iwc.int/entanglement

New Study Estimates Sea Turtle Bycatch in the Millions. (2010, April 05). Retrieved January 29, 2019, from https://nicholas.duke.edu/about/news/new-study-estimates-sea-turtlebycatch-millions