Economic Analysis of Alternative Escapement Goals (April 2015)
Scientists from the University of Washington and BBSRI conducted an analysis of alternative sockeye salmon escapement goals for Bristol Bay. The 18-month study drew upon academic and industry (via an Advisory Panel) expertise to examine the economic and biological impacts of alternative escapement goal policies for Bristol Bay. The study stemmed from a decision by the Alaska Board of Fisheries in December 2012 to delay adoption of new escapement goals until the economic implications of alternative escapement goal policies could be examined.
The study used a simulation modeling approach (management strategy evaluation or MSE) and found that taking the economics of the fishery into account affects the choice of the best escapement goal policies. All escapement goals examined in the study were biologically sustainable.
Simply trying to maximize the yield (i.e., maximum sustained yield or MSY) does not actually yield the greatest annual catch from the Bristol Bay sockeye salmon fishery, nor does not maximize the value of the catch. This is in part because there are fundamental limits to how many fish can be caught and processed in very large run years produced by MSY-based management. Larger escapements can reduce catches in small-run years but limits to capacity cannot always take advantage of large runs. In addition, the average value of the catch generally falls with run size due to limits on volume created by economics and the product mix produced from the catch. From an economic value perspective, escapement goals that provide a more stable but slightly smaller annual harvests are preferable to pursuing the theoretical maximum average catch.
The study produced two documents (links below). The first report examines the biological and economic consequences of four alternative escapement goal policies and the second report is a technical analysis of methods used to estimate the escapement needed to provide the theoretical maximum catch (MSY) from Bay sockeye stocks.
Cunningham et al. (2015b) Evaluation of alternate methods to estimate biological escapement goals (i.e., theoretical maximum yield escapement goals, aka BEGs).
Study team: Michael Link, Drs. Ray Hilborn, Chris Anderson, Curry Cunningham, and Jocelyn Yun-Ling Wang
Advisory Panel: Jeff Regnart, Vince Webster, Fritz Johnson, Matt Luck, Abe Williams, Bill Munroe, John Boggs, John Heins, Dr. Matt Reimer, Michael Link
For more information about this study, contact Michael Link.