Estimation of Size Selectivity and Movement Rates from Mark–Recovery Data

Abstract

Size selectivity, movement rates among spatial strata, and size-dependent mortality rates were estimated from mark–recovery data of Pacific halibut (Hippoglossus stenolepis). Growth rates, area- and time-specific fishing mortality on fully vulnerable individuals, and tag return rates were assumed known from other data. We obtained similar estimates from a model that considered movement to take place immediately after tagging and a model that assumed that movement takes place once each year. The inability to distinguish between one-time and annual movement is most likely due to the fact that tagged juveniles were not recovered until 3–5 yr later when they became vulnerable to the adult fishery.