Significant process is being made with existing projects focusing on the Eastern Tuna and Billfish fisheries (ETBF), but the need to develop and test suites of stock indicators with associated reference points and decision rules for use by the FAGs for each fishery remains, particularly for the Southern and Western region (SWTBF). The need is also urgent, given the imminent introduction of TAE/TAC based management plans and the need to formally evaluate them on an annual basis.

Given the potential difficulties and limitations of using only CPUE as an indicator of stock status there is a need to also consider other indicators, e.g. ones which might reflect local depletion, an issue which is of real concern. Standardisation of such indicators also needs to be considered. Different indicators (e.g. CPUE or mean length in the catch) reflect different aspects of the population dynamics, and there is increasing recognition of the value of considering a suite of indicators rather than relying on a single one. There are currently only limited and relatively unsophisticated frameworks for combining information from several indicators. There is a need to develop this further, and to design defensible and robust frameworks to use in management decision-making. There is also a need to test the robustness of suites of indicators within the context of a feed-back management loop rather than simply in a non-feedback sense.

Although this work is needed for, and will focus on the management of the domestic fisheries, there is an international need for this research. Tunas and billfish harvested in the SWTBF form part of the Indian Ocean stocks which fall under the remit of the Indian Ocean Tuna Commission (IOTC). The research proposed here was identified as a high priority task at recent IOTC Working party meetings.