Going dark: Fishing vessels are switching off their tracking systems to avoid detection


Steps to regulate fisheries and protect marine reserves can be undone at the flick of a switch

Something fishier than normal occurred off the coast of Ecuador in 2014: a Panamanian fishing vessel disappeared from maritime tracking systems on the western side of the Galápagos Marine Reserve, only to reappear 15 days later, this time on the east of the reserve. According to Oceana, an ocean conservation NGO, it’s possible that the vessel was intentionally ‘going dark’ to hide illegal fishing activity.

It’s surprisingly common for fishing vessels to simply switch off their tracking systems – the most commonly used being the Automatic Identification System (AIS), which publicly broadcasts location information. ‘We need to be asking the obvious question: Why would any vessel want to hide its tracks?’ says Beth Lowell, senior campaign director for illegal fishing at Oceana.

The organisation has released a new report detailing the extent of both fishing activity and ‘gap events’ (instances where AIS transmissions aren’t detected for more than 24 hours) along the border of Argentina’s Exclusive Economic Zone (EEZ) – a hugely popular location for international fishing vessels. Between 1 January 2018 and 25 April 2021, it reports that more than 800 fishing vessels conducted nearly 900,000 hours of apparent fishing within 20 nautical miles of this invisible border between Argentina’s national waters and the high seas. During this time, there were more than 6,000 instances in which these fi shing vessels appeared to go dark, potentially by disabling their AIS devices, totalling 600,000 hours.

Chinese-flagged squid jiggers were responsible for two-thirds of these incidents, although they weren’t the only culprits. Spanish trawlers went dark more than three times as often as Chinese vessels. Given this activity, the report points to the risk of illegal behaviour: ‘Disabling AIS hides fishing vessel locations from public view and could mask potentially illegal behavior, such as crossing into Argentina’s EEZ to fish.’

Argentina’s shortfin squid fishery generates an average of US$597 million for South America’s economy each year. According to seafood distributor Roda International, China imported more than 150,000 tonnes of cuttlefish and squid in 2019. The lure of this high-reward market may be prompting clandestine activity, says Oceana.

Chinese fishing vessels have often greeted the Argentinian Coast Guard with hostility. In 2016, a Chinese trawler managed to sink itself after ramming a Coast Guard vessel; and in 2018, four Chinese fishing vessels teamed up to protect a fifth vessel that the Coast Guard was pursuing for suspected illegal fishing.

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Any non-compliance with maritime law has consequences. Due to the short life cycle of the shortfin squid and its key role in the food chain, illegal and unaccounted fishing of the species would destabilise the population the following year, causing ecosystem-wide disruption. Similarly, any fishing activity in marine protected areas can severely disrupt sensitive ecosystems. ‘When you get big boats with massive nets illegally coming through protected areas such as the Galápagos Marine Reserve, it’s completely detrimental to the protection process and undoes all of the hard work of trying to improve fi sheries and protect marine life,’ says Marla Valentine, an illegal fi shing and transparency analyst at Oceana.

This recent report is the latest in a series of accounts on the same issue. In 2015, Oceana reported that an Australian commercial fishing vessel disabled its AIS near the Heard Island and McDonald Islands Marine Reserve on ten separate occasions. In 2014, a Spanish-flagged trawler turned off its AIS system at least 21 times, resulting in 8,000 hours of unaccounted activity.

Legal loopholes and patchy enforcement between different states are part of the problem. The International Maritime Organisation requires large vessels to carry AIS, but it’s down to national governments to decide if and how requirements apply to fishing vessels in their waters. The EU requires all vessels longer than 65 feet to have AIS, but Canada exempts all vessels from requirements. Fishers can also legally decide to hide from public view for legitimate reasons – when in waters commonly used by pirates, for example.

Oceana has long recommended that governments mandate continual use of vessel-tracking systems by all commercial fishing vessels. It also argues that AIS systems should be modernised so that fishers can’t tamper with the co-ordinates on their systems or enter false vessel- identification numbers. These steps could help to geolocate the sources of catches. ‘Increased transparency can help deter illegal fishing, prevent unauthorised fishing in a nation’s waters and improve monitoring of fishing around the world,’ says Lowell.

Modernising vessel-tracking systems could also improve conditions for workers. ‘For years, we thought about illegal and unaccounted fishing as being about the fish and the damage to marine ecosystems. But we’re increasingly aware that fishing on the high seas is rife with human rights abuses,’ adds Valentine. ‘Because of humanitarian and environmental reasons, it’s so important for people to know where their seafood is coming from and how it’s being caught.’

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