Uncertainty in Stock Composition Estimates of Oceanic Steelhead Trout Using Electrophoretic Characteristics: Comments on a Recent Study

Analysis of stock composition of mixed-stock fisheries using electrophoretic data is gaining acceptance for both research and management purposes. However, a thorough understanding of the influence of sample size, stock separation, and estimation procedures is required before meaningful results can be obtained. An example from the recent literature is reanalyzed to demonstrate this conclusion. We show how widely different results are obtained from the same data when analyzed by two different models. Some insight into these differences is achieved through a Monte Carlo simulation study.