Proposal to amend Assessment of Two Methods for Estimating the Composition of Chinook Encounters Early in the Fishing Season Draft

In Assessment of Two Methods for Estimating the Composition of Chinook Encounters Early in the Fishing Season (Conrad, Garber and Rose 2020) an adequate sample size was defined as ≤ 20% coefficient of variation (CV) of the proportion of legal-size and marked encounters. The threshold of ≤ 20% CV of the proportion LM encounters has been long in-use for evaluating TF and VTR sample sizes post-season. However, the 20% CV criteria presents challenges when the proportion of LM encounters is low in either the TF or VTR programs. When there are lower proportions of LM encounters (<10%), the sample size needed to achieve the 20% CV exponentially increases.