Impacts of distorted fishery statistical data on assessments of three surplus production models

摘要

We evaluated the effect of various error sources in fishery harvest/effort data on the maximum sustainable yield (MSY) and corresponding fishing effort (E MSY) using Monte Carlo simulation analyses. A high coefficient of variation (CV) of the catch and effort values biased the estimates of MSY and E MSY. Thus, the state of the fisheries resource and its exploitation was overestimated. We compared the effect using three surplus production models, Hilborn-Waters (H-W), Schnute, and Prager models. The estimates generated using the H-W model were significantly affected by the CV. The Schnute model was least affected by errors in the underlying data. The CV of the catch data had a greater impact on the assessment than the CV of the fishing effort. Similarly, the changes in CV had a greater impact on the estimated maximum sustainable yield (MSY) than on the corresponding estimate of fishing effort (E MSY). We discuss the likely effect of these biases on management efforts and provide suggestions for the improvement of fishery evaluations.