A Multilevel and Multiobjective Programming Model of Hawaii Commercial Fisheries

Project findings published as part of the SOEST-JIMAR publication series:
"A multilevel and multiobjective programming model for the Hawaii fishery: Model documentation and application results", 1999. Mingling Pan, PingSun Leung, Fang Ji, Stuart T. Nakamoto and Samuel G. Pooley. With user's manual, "Fisheries management decision support system (FMDSS): User's manual", 1999. Omar F. El-Gayar and Fang Ji

See SOEST-JIMAR Publications page and Journal Publications page for other publications by Leung et al. and other PFRP investigators

Progress Report - July 1998

P.I. NAMES: PingSun Leung, Stuart Nakamoto and Sam Pooley

GRADUATE ASSISTANTS: Jill Muraoka (MS Candidate), Minling Pan (Ph.D. Candidate) and Fang Ji (Ph.D. Candidate)

Purpose of Project:

To develop and test a multilevel and multiobjective programming model of the Hawaii commercial multifishery. The multilevel aspect of the model is an attempt to incorporate and analyze objectives of both the policy makers and fishermen. In addition, the use of a multiobjective model is essential as the complexity of fishery management requires the implementation of more than one general objective.

Progress during FY 1998:

A. Determine Management Goals of the Hawaii Multifishery.

This task is completed. The results were presented at the Fishery Management Under Uncertainty Symposium, June 2-5, 1998, in Bergen, Norway. Results were also presented at the Ocean-Scale Management of Pelagic Fisheries: Economic and Regulatory Issues, Nov. 12-13, 1997, East-West Center, University of Hawaii. The results will also be published in a forthcoming issue of Fisheries Research. The abstract of this forthcoming paper, which provides a good summary of the research results of this task is reproduced below.

Abstract of paper entitled "Evaluating Fisheries Management Options in Hawaii Using AHP":

Fisheries management is typically characterized by multiple and often conflicting objectives. The Western Pacific Region Fishery Management Council (WPRFMC) is the authority for managing EEZ (exclusive economic zone) fisheries in Hawaii. The array of multiple objectives coupled with the heterogeneous composition of WPRFMC creates a complex decision-making environment for fishery management in Hawaii. In this paper, we applied the analytic hierarchy process (AHP) to evaluate four alternatives for limiting entry of longliners into the Hawaii pelagic fishery. We first elicited the factors deemed to be important for a sustainable pelagic fishery using a questionnaire survey, followed by another questionnaire to elicit judgments from all of the individuals involved in the decision-making process of WPRFMC. While there is considerable variation among individuals, the overall weighting of objectives and ranking of alternatives is robust in the sense of being consistent across all four bodies of the WPRFMC. There was no statistical difference in mean results among the WPRFMC bodies at the 5% level. This experience demonstrated an application of the AHP process in fishery management. The results of the present evaluation of the alternatives for limiting entry of longliners are comparable to earlier decisions. As compared to conventional decision-making, this process has the advantages of timeliness, quantification, and documentation. It may also provide policy analysts with insights into potential conflicts and tradeoffs before the decision-making process unfolds.

B. Modify and Extend the NMFS Linear Programming Model

This task is essentially completed. A bilevel and multiobjective programming model of Hawaii's multifishery has been developed. Figure 1 (Fig. 1 PDF) shows the overall framework of the model. The bilevel aspect of the model incorporates and analyzes objectives of both policy makers and fishermen. The current model covers nine fleet categories including commercial, semi-commercial, charter, and recreational fleets; five fishing areas; four fishing seasons; and 14 species or species groups, of which ten are the possible targets in Hawaii's multifishery. Fleet size can vary by season, and the annual fixed cost is included as long as the vessel is active in one season of a year. In addition, a nonlinear relationship between CPUE and total fishing effort is incorporated into the model. Bycatch is considered in the model, and the amount and proportion of targeted catch and bycatch vary depending on fleet, target, area, season, as well as total fishing effort. Fishermen's objectives are incorporated into the model by three entry conditions trip, crew, and owner - for each fleet. The above features are incorporated into a mixed-integer nonlinear programming model. Under various objectives or policy options facing Hawaii's fisheries, the model provides the optimum solutions in terms of fleet mix, harvest level of the different species, fish resource allocation among the different effort groups (fleets), and spatial and seasonal distribution of the efforts. Compared to the previous NMFS linear programming model, the present model appears to produce more realistic solutions representing Hawaii's multifishery.

C. Operationalize the Developed Model on a Microcomputer.

The model has been computer-coded using the software program GAMS for solution. Appropriate databases of inputs have been developed using MS FoxPro to facilitate the evaluation of different scenarios, and to facilitate future updating, as more and improved data become available. Interfaces (computer routines) have also been developed using MS Excel to extract relevant model results for clarity of presentation. The entire modeling system has been integrated as a Fishery Management Decision Support System (FMDSS). The system is currently under testing to clean out all the bugs before distribution to potential users.

D. Scenarios Development and Evaluation.

The model has been used to evaluate the impact of closing area within 75 nm from the shore for the longliners. It was estimated that such an action would have incurred an economic efficiency loss of $0.44 million. Or, in other words, the cost of avoiding conflict between the longliners and the small boats amounted to about $0.44 million. The model was also used to estimate the tradeoffs between the commercial and recreational fisheries. At the current level of recreational participation, the economic rent loss per recreational trip was estimated to be about $12.

A technical report documenting the current model formulation and the detailed results is under preparation. The model and results were presented at the Ocean-Scale Management of Pelagic Fisheries: Economic and Regulatory Issues, Nov. 12-13, 1997, East-West Center, University of Hawaii.

3. Plans for the next four months:

A. Determine Management Goals of the Hawaii Multifishery.

Completed

B. Modify and Extend the NMFS Linear Programming Model

Complete the technical report documenting the model structure.

C. Operationalize the Developed Model on a Microcomputer.

Complete testing of the Fishery Management Decision Support System (FMDSS) for distribution.

D. Scenarios Development and Evaluation.

Complete technical report summarizing results.

4. List of Papers Published in Refereed Journals:

Leung, P.S., J. Muraoka, S.T. Nakamoto, and S. Pooley. "Evaluating Fisheries Management Options in Hawaii Using Analytic Hierarchy Process (AHP)," forthcoming in Fisheries Research.

5. Other Papers, Technical Reports, etc.

A Bilevel and Multiobjective Programming Model of Hawaii's Multifishery, forthcoming technical report.

Fisheries Management Decision Support System (FMDSS), forthcoming technical report.

This page updated August 17, 2006