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Ghost gear busters

Ship & Boat International eNews: July/August 2022

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The Lax Kw’alaams First Nation marine territory in Prince Rupert, BC, Canada has been plagued by a problem: over time, its fishing grounds have become polluted with discarded or lost fishing gear. As well as posing a risk to boat propellers and outboards, this ‘ghost gear’ debris has the potential to entangle, injure and kill marine mammals, fish and birds. The World Wildlife Fund (WWF) cites studies revealing that 90% of fish caught in ghost gear are of commercial value, so this abandoned junk can also reduce harvests and even drive fisheries out of business.

 

Lax Kw’alaams isn’t the only indigenous territory affected: the problem has grown so big that, in 2019, the Canadian government rolled out the Ghost Gear Fund, initially valued at CA$8.3 million (US$6.5 million). In 2021, this funding was increased by CA$10 million and allocated to 37 ghost gear-recovery programmes, 14 of which took place within indigenous communities. According to the Canadian Coast Guard, around 739tonnes of abandoned fishing gear have been recovered from the country’s waters since the funding was introduced.

 

This funding supported Lax Kw’alaams Fishing Enterprises (LKFE), a business entity of the Lax Kw’alaams First Nation, and BC-based Shift Environmental Technologies entered into a two-year project to locate, remove and responsibly dispose of local abandoned fishing gear. To assist with this task, LKFE and Shift utilised a single, customised SEAMOR Chinook unit. Measuring 0.68m in length, 0.38m in width and 0.4m in height, this ROV type has been deployed in various underwater and deepwater search and recovery missions in the past. In 2021, for example, this model was used by the US Federal Aviation Administration and National Transportation Board to locate a sunken cargo plane in the Pacific Ocean. Capable of descending to 300-600m, depending on the model selected, the Chinook has also proven a safer alternative to sending human divers into excessively cold, turbulent or restricted waters.

 

The two-year project comprised three clean-up missions within the Lax Kw’alaams fishing grounds, focusing on the Area B Crab Fishery Management Area. “Each deployment varied widely depending on conditions and tides,” Katie Smith, marine projects lead at Shift, tells Ship & Boat International. “The project required an ROV: the alternative is using a commercial diver, which is a more expensive and riskier method of gear retrieval.” To this end, the Chinook relied on a Teledyne Blueview P900-45 multibeam sonar and a Blueprint Subsea SeaTrac lightweight USBL acoustic positioning system: both essential tools, given the poor visibility conditions under the surface. SEAMOR explains: “The most successful method was to find strings of crab pots using a towed or hull-mounted side-scan sonar; then to revisit those spots with the ROV, to get footage of the target. The ROV footage confirmed that the debris was crab pots and prawn traps,  helped determine whether it was retrievable, and identified the locations of the terminal ends of the string.”

 

The work vessel was fitted with a grapple, about 1.5-1.8m in length, which was dragged through the locations of the terminal ends to retrieve the pots and traps. In all, the Chinook helped the team to recover some 630kg of ghost gear, including more than 425m of abandoned rope, as well as plastics and marine debris. This ‘haul’ was then transported to the nearby Port Edward Harbour Authority, for cleaning and safe storage.

 

The successful project should nonetheless be seen as the start of a much longer-term campaign. Smith says: “There is certainly still remaining gear: the Lax Kw’alaams traditional marine territory is a vast area, and way too big for any one boat to cover in such a short time frame.” However, SEAMOR says, with the ROV and training acquired through the ghost gear retrieval programme, the Lax Kw’alaams community should be well equipped to organise future retrievals.