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作者 A'mar, Zoetrope Teresa
書名 A management strategy evaluation of the harvest policies of the North Pacific Fishery Management Council used for the fishery for walleye pollock (Theragra chalcogramma) in the Gulf of Alaska
國際標準書號 9781109124590
book jacket
說明 244 p
附註 Source: Dissertation Abstracts International, Volume: 70-04, Section: B, page: 1989
Adviser: Andre E. Punt
Thesis (Ph.D.)--University of Washington, 2009
Management strategy evaluation (MSE) is the use of simulation testing with feedback to examine the robustness of management strategies to error and uncertainty. MSE involves using an operating model to represent the true underlying dynamics of the resource and generate future data, and an empirical or model-based harvest control rule (the management strategy) to determine management actions. The structure of the management strategy can be selected to attempt to satisfy desired (but conflicting) management objectives. The results of an MSE are performance measures that quantify the effectiveness of the estimation model and, more generally, the management strategy
An MSE was performed on the management strategy used by the North Pacific Fishery Management Council to manage the Gulf of Alaska walleye pollock ( Theragra chalcogramma) fishery. The current and several alternative management strategies were evaluated with respect to error and environmental forcing. The "true" resource dynamics represented in the base operating model were consistent with the current stock assessment. The operating models were fit to stock assessment data using Bayesian methods, and subjected the management strategies to parameter uncertainty, and process and observation error, at a minimum. The management objectives involved keeping spawning biomass near the reference level of S B40% and achieving high stable catches without exceeding the overfishing limit. Implementation error was not considered
Extensions to the base operating model were made to incorporate proxies for environmental forcing: (a) annual natural mortality-at-age was predicted from the biomass of the pollock predators arrowtooth flounder (Atheresthes stomias), Pacific cod (Gadus macrocephalus), and Pacific halibut (Hippoglossus stenolepis); (b) changes in future average age-1 recruitment were based on historical patterns which represented regime shifts; and (c) annual age-1 recruitment was projected using climate indices from Intergovernmental Panel on Climate Change (IPCC) model output which characterized environmental variability and climate change
The current management strategy appeared to meet management sustainability goals. The "dynamic B0" management strategy performed similarly to the current management strategy, with a slight improvement in some scenarios. The "sliding window" management strategy performed better than the current management strategy in some scenarios, but had a higher risk of overfishing
School code: 0250
Host Item Dissertation Abstracts International 70-04B
主題 Agriculture, Fisheries and Aquaculture
Operations Research
0792
0796
Alt Author University of Washington
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