UW Aquatic & Fishery Sciences Quantitative Seminar

Tim Essington

UW School of Aquatic & Fishery Sciences

Quantifying ecological impacts of dedicated access privilege (DAP) programs

Abstract

There is a growing interest in how various "rights-based", or "dedicated access privilege" (DAP) programs might promote more sustainable fisheries. Although these management actions are primarily designed to improve the economies of fishing fleets, there is some indication that they might also reduce wasteful, destructive or unsustainable fishing practices. We evaluated changes in several metrics to measure the magnitude of response from 16 DAP fisheries in North America. We developed simple time series models to measure the change in response variables after DAP implementation, and also developed several alternative ways to measure these responses that use different types of data as reference data. After estimating effect sizes for individual fisheries and metrics, we pooled estimates using a random effects model. We found marked changes in DAP fisheries across a suite of metrics, but the nature of the response was unexpected: rather than observing changes in the mean state of fisheries following DAP implementation, we instead found substantial reductions in the interannual variance. These effects were not uniform across fisheries, but instead were strongest in U.S. DAPs implemented in the Pacific Ocean. We suggest that the primary response of fisheries systems to DAPs is to become more predictable from year to year, but that there may be important differences in DAP programs that mediate the magnitude of this effect.