New research reveals the secret life of FADS

by Bernadette Carreon | 11 December 2018 | News

A fish aggregating device (FAD) is pictured in the Pacific Ocean. Photo: SeafoodSource

Honolulu, HawaiiTonnes of plastic waste smashing into reefs, entanglement of vulnerable wildlife, and long journeys across the Pacific are only part of the life of the tens of thousands of Fishing Aggregate Devices (FADs) placed in the ocean every year by the tuna industry.

Now the mysteries of FADs are starting to reveal themselves in a FAD tracking project being conducted by the Parties of Nauru Agreement (PNA).

“We took an interest in FADs back in 2009 and 2010 because we realised it wasn’t just an important part of the fishery, but was one of the main causes of some of our conservation problems,” Maurice Brownjohn, PNA commercial manager, told reporters this week on the sidelines of the Western and Central Pacific Fisheries Commission taking place in Honolulu.

Today’s fishing no longer relies on Mother Nature alone as FADs have made it easier from fishermen to find fish.

Technological advances in FADs are making tuna-catching more efficient, especially for commercial fishing. There is a threat that without more regulation they could end up depleting the stocks.

FADs have evolved. Devices now have sonar and satellite buoys attached with allows the fishing industry to know what’s swimming underneath the boats even if they are miles away from the vessels.

The PNA first started tracking FADs in January of 2016 by requiring FAD buoys to be registered and to report their location to PNA’s Fisheries Information Management System (FIMS).

The PNA has many questions. “If there are a lot of FADs in the water, does it impact the schooling behaviour of the fish? Does free school fishing suffer if fishing boats are deploying many more FADs? The information coming from other oceans, where there is a very high proportion of FADs suggests that more do impact free school fishing.

“And then this has an impact on your stock assessment and your fisheries modelling and everything else”, Brownjohn said.

The directive from PNA ministers to start the tracking program led to FAD workshops in Brisbane in June and in Honiara in late October to upgrade the FAD programs to a policy document to be endorsed by PNA leaders. The FAD tracking program has started to reveal the life of FADs, many of which can float cast distances after they are no longer being used for fishing.

As marine debris, FADs have been found to smash into reefs, repeatedly freeing themselves only to again be driven back onto the coral damaging a different section of reef.

Damage to vulnerable species such as sea turtles and sharks can happen when they accidentally get entangled in the netting or ropes that lie below a FAD.

Environmental group PEW recommends that the Commission mandate that fishing vessels adopt FAD designs that reduce the entanglement and deaths of sharks and turtles.

Meanwhile, the PNA is advancing FAD management to improve reporting of the current FAD tracking trial, integrate FAD log sheets with electronic reporting by fisheries observers, develop a PNA FAD buoy tracking and registration measure, and address ecological issues associated with FADs, including FAD retrieval and liability for beaching of FADs.

Brownjohn said with the new technology, commercial operations arena basically “fishing from the office now.” According to PNA, although not all are used, there are an estimated 50,000 to 80,000 FADs deployed in PNA waters annually.

The work of the PNA FAD tracking program has highlighted the increasing technological sophistication of FADs in the purse seine fishery, which allows fleets to “cherry pick” FADs to set on. This happened through a centralised monitoring system which directs purse seine vessels to particular FADs, eliminating the need for vessels to visit individual FADs in search of schools of tuna.

“This allows fishing vessels to focus fishing on FADs with the largest schools, which has implications for tuna stocks and management of the fishery,” PNA said.

In this week’s WCPFC meeting in Honolulu, FAD closure was again under scrutiny, with concern about the substantial impact of FADs on bigeye tuna populations, which has in the past been on the borderline of overfishing.

“Largely because of PNA’s annual FAD moratorium, a much lower share of the catch in this region is taken by fishing on FADs,” said Ludwig Kumoru, CEO of PNA. “It is likely that this contributes to the more positive status overall of the major Western and Central Pacific Ocean tropical tuna stocks.”

The FAD tracking program is in its infancy and has only just begun to reveal a potential treasure trove of information. Fisheries managers and conservation representatives alike, hope that information from the program will make it easier to protect tuna as well as the ecosystems that make up their ocean home.