Purse Seine Fishing Technique is Draining PNG's Tuna

RD Tuna Operations in Madang Province (Credit: PNG Business Advantage)

Kingtau Mambon | UPNG Economics Tutor

The recently proposed Chinese multi-functional fishery industrial park in Western province raised concerns about the marine resource’s depletion in PNG waters. Amongst other factors, fishing techniques are major determinants of the extent to which marine resources can be depleted. The two methods of catching tuna commonly used in PNG’s Economic Exclusive Zone (EEZ) are the long-line, and purse seine fishing methods.

Purse Seine is mostly used due to two advances to its technology:  It uses sonars which locate schools of tuna and Fish Aggregating Devices (FAD), which are floating objects designed to attract tuna.

Tons of Tuna by Fishing Methods (1999-2019)

As purse seine fishing is widely used, there is a risk that it could deplete tuna stocks. In 2019, Parties to Nauru Agreement (PNA) countries of which PNG is also signatory, banned the use of FAD because purse seiners deployed approximately 50,000 to 80,000 FADs which threatened juvenile tuna stock. A ban of this nature was appropriate for PNG, as it was reported that two out of PNG’s three main tuna species (skipjack, yellowfin, and bigeye), were fished to near extinction. Further, four years before this ban, the overfished status of tuna in PNG waters was declared to be 80 percent utilization rate. It was worse in 2012 when tons of tuna caught exceeds the maximum sustainable production by 44 percent.

Tuna depletion can be further exacerbated by Illegal Unreported and Unregulated (IUU) fishing. Encroachers have been caught not only in the tuna-rich Bismarck Sea of New Guinea Islands but also in the Coral Sea in the Southern region. Despite warning from the European Union (EU) concerning the growing demand for PNG canned tuna, the current PNGs IUU fishing index is 60 percent below the median rank of Oceania  Countries. The IUU fishing index is a measure that indicates the extent to which countries can limit illegal fishing. IUU fishing score ranges between 1 and 5 where 1 indicates best and 5 indicates worst. When ranked from highest to lowest IUU fishing index, PNG’s rank is 5th compared to the Solomon Islands and Australia, indicating it is unable to effectively prevent illegal fishing.

In summary, the depletion of tuna stock through illegal, purse seine fishing must be addressed. The government also needs to look at supporting and promoting low-cost approaches to long-line fishing to support a transition to more sustainable methods of fishing. On the other hand, the established regulations and management of tuna fisheries and FAD management policy should be fully utilized to guide purse seiners tuna production.

The tuna industry needs greater enforcement and compliance of both regional and domestic fishing policy so that tuna is both enjoyed today and in the future.

Source: Western and Central Pacific Fisheries Commission (WCPFC), 2020 and Pacific Environmental Portal, 2016.