System Dynamics Modeling of Individual Transferable Quota Fisheries and Suggestions for Rebuilding Stocks

Edward J Garrity

doi:10.3390/su3010184

Abstract

This paper develops a system dynamics model of Individual Transferable Quota (ITQ) systems in order to differentiate ITQ from total allowable catch (TAC) effects and to identify areas where policy changes and management improvement may be most effective. ITQ systems provide incentives for long-term stewardship but when fisheries are managed “at the edge,” the incentives are inadequate for stock rebuilding. The free-market design of ITQ systems means that fishermen may be in conflict with the long-run, public sustainability goals of fishery management. An adaptive control scheme with a contingent public/private transfer payment is proposed to improve long-term results for both the local community and the general public.

Highlights

Many salt water fish stocks are in decline worldwide
In the case of setting total allowable catch (TAC), management may be reluctant to act on uncertain scientific advice that indicates the fish stock is at an unhealthy level
A common scenario is that the scientific information provided was reasonable and the stock will likely continue to decline since management has delayed taking action [8]

Summary

Introduction

Many salt water fish stocks are in decline worldwide. Overfishing has led to the complete collapse of numerous fisheries including those for important and well publicized species, such as northern bluefin tuna and Atlantic cod [1,2,3]. If management delays TAC reduction, there is the possibility that the better scientific information may reveal that the stock recovered. A common scenario is that the scientific information provided was reasonable and the stock will likely continue to decline since management has delayed taking action [8]. When this occurs management is forced to take even more extreme measures to help stock recovery. Tough management actions typically fuel political resistance, which causes further delay and leads to a harmful reinforcing loop [8]

Results

Discussion

Conclusion