A History of the Tuna-Dolphin Problem: Successes, Failures, and Lessons Learned

Multispecies aggregations of tuna, dolphins, and seabirds are prevalent and conspicuous in the vast waters of the eastern tropical Pacific and form the basis of a commercial fishery for yellowfin tuna (Thunnus albacares) through setting on schools of dolphins, which is among the largest tuna fisheries in the world. Incidental dolphin mortality associated with the development and early years of the fishery was high; by 1993 it was estimated that eastern spinner dolphins (Stenella longirostris orientalis) had been reduced to 44% and northeastern offshore spotted dolphins (S. attenuata attenuata) to 19% of pre-fishery levels. Efforts to reduce this mortality began at the inception of the fishery and comprised a diverse array of approaches: modifications to fishing methods and fishing gear (backdown, Medina panel, high-intensity floodlights, swimmers to disentangle and release dolphins); U.S. legislation (through the U.S. Marine Mammal Protection Act, MMPA, and subsequent amendments); international agreements (including the International Dolphin Conservation Program that established dolphin mortality limits, and the legally binding multilateral Agreement on the International Dolphin Conservation Program); and economic incentives [notably through establishment of the U.S. dolphin-safe label and positive certification by the Marine Stewardship Council (MSC)]. Together, these bycatch mitigation efforts have been remarkably successful; dolphin mortality due to entanglement as recorded by fisheries observers (hereafter, entanglement mortality) has been reduced by > 99%. Despite this, the degree to which dolphin populations have recovered remains unclear. Multiple lines of evidence indicate that individual dolphins experience multiple sets in their lifetimes and although causality has not been established, research suggests that chase and encirclement might have impacts on dolphins in addition to entanglement mortality. These impacts potentially include increased fetal and/or calf mortality, separation of nursing females and their calves, decreased fecundity, increased predation, disruption of mating and other social systems, and ecological disruption. The strong management emphasis on monitoring entanglement mortality, and the infrastructure necessary to support this monitoring (in particular, 100% observer coverage on large purse-seiners) require funding to the extent that other activities, particularly continued surveys to monitor stock status and clarify the potential influence of other effects of the fishery on dolphin populations, are currently inadequately funded.

Improvement on small-scale tuna fisheries data quality through the application of e-logbook system

Tuna and tuna-like fisheries play a vital role in Indonesian livelihood, especially in the archipelagic waters. However, despite the importance, the concern in general data collection activities for tuna, i.e., limited, with incomplete scientific knowledge and insufficient data has hampered the assessment. The purpose of this study was to analyse on how fisheries-dependent data system could transform the data quality. E-logbook has the best attribute for reaching the goals, especially for small-scale tuna fisheries. Characterised by low cost and vast spatial and temporal coverage, it is convinced on why the program should be expanded and monitored carefully. Analysis on fisheries indicators showed a promising result, especially for filling the gap which could not be covered by research.

Small scale tuna fisheries profiles in the Indonesia archipelagic waters

Indonesia is one of the largest tuna producers in the world, which contributes 16% to world tuna production. The dominant tuna species catched in Indonesia are Albacore Tuna (Thunnus alalunga), Madidihang/Yellowfin Tuna (T. albacares), Big Eye Tuna (T. obesus) dan Southern Bluefin Tuna (T. maccoyii). The tuna fisheries have contributed significant jobs or livelihood to the coastal communities. Profit and revenue sharing is a common remuneration system found on tuna fisheries though out Indonesia. However, these fishers are vulnerable given their economic and welfare conditions and of usually limited options of others livelihood. Small fishers have limited access to livelihoods, access to finance and access to skills or fishing technology. Therefore, the inclusion of socio-economic performance or indicators into the tuna fisheries management is crucial in Indonesia.

Sustainability Analysis of Tuna (Thunnus sp.) Fishery in Sendang Biru, Malang Regency

Tuna capture fisheries have a very important value and meaning for the socio-economic life of coastal communities, either directly or indirectly. On the other hand, the catch of tuna has decreased from an ecological aspect based on the exploited status, production, and the value of CpUE (Cath per Unit Effort), the length of the fish caught, and the amount. The research objective was to analyze the sustainability status of tuna fisheries from 3 dimensions. This study was a survey of 76 respondents in the Sendang Biru Malang districts. The method used the Multi-Dimensional Scaling (MDS) analysis using the software Rapfish (Rapid Appraisal for Fisheries). The results showed that the sustainability status to be seen from 3 dimensions, ecology, economic, and social, which showed that the level of sustainability of tuna fishery from the economic and social dimensions was enough sustainable. For the ecological dimensions, it shows less sustainability. In general, the level of sustainability of tuna fishery in the Sendang Biru is enough sustainable. There need activities related to environmental conservation to increase ecological sustainability. In addition, it is necessary to hold counseling and training on aquatic ecosystems so that they are utilized in the short term and in the long term.

Tuna Fisheries Conservation and Management in the Pacific Islands Region

The Korean tuna fishing fleet has a long history of participation in the tuna fisheries of the Western and Central Pacific Ocean (wcpo), the largest tuna fisheries in the world. As one of the largest distant water fishing fleets operating in the wcpo, Korea has a strong interest in maintaining access to both eez s and the high seas, and ensuring sustainability of the region’s tuna stocks. The regulatory environment for tuna fisheries in the wcpo is complex and multi-layered, with regional, sub-regional and national legislation, regulation and policies all affecting tuna fishing vessels and operations. Management of tuna fisheries within Pacific Island eez s is increasingly being tightened, including through the introduction of zone-based management approaches, and Pacific Island countries are also advocating for improved management of tuna fishing in the high seas. While all four primary tuna species in the wcpo are currently considered healthy, catch rates and economic conditions in the southern and tropical longline fisheries are in decline and catch reductions will be necessary to improve catch rates and increase economic returns for longline vessels. Within this context, the Korean distant water fishing fleet will need to strengthen engagement and cooperation with Pacific island States in order to maintain their competitiveness.

Bioeconomic analysis of skipjack tuna fisheries in North Gorontalo Regency, Indonesia

The model of the skipjack tuna resource management that can provide maximum rent can be done with a clear ownership regime (sole owner) or in the condition of MEY balance. However, the management and utilization of skipjack tuna resources must also consider the factors that can result in overfishing of both biological and economics overfishing. This study aims to assess the management and utilization of skipjack tuna fisheries resources in North Gorontalo Regency using a bioeconomic approach. Data processing is done by approaching the bioeconomic model using skipjack tuna fisheries biological and economic parameters. The results showed that the maximum rent obtained in skipjack fisheries in North Gorontalo Regency was at the MEY regime compared to the MSY and OA regime. However, based on the actual data obtained, it is known that the average production of skipjack tuna in North Gorontalo Regency has not reached the optimum catch value in the equilibrium condition of MSY (hMSY ), but in some period the actual catch value has passed the optimal catch value (hMSY ), this means that skipjack tuna has overfished (biological overfishing). While the actual production value of skipjack tuna catches in North Gorontalo Regency has passed the production of optimum MEY (hMEY ). This condition indicates that actually skipjack tuna resources have experienced an economic overfishing.