ESTIMATING MIGRATION RATES USING TAG-RECOVERY DATA

Tag-recovery data are used to estimate migration rates among a set of strata. The model formulation is a simple matrix extension of the form ulation of a tag-recovery experiment discussed by Brownie et al. (1 98 5, Statistical Inference from Band-Recovery Data-A Handbook, 2nd edit ion, Washington, D.C.: U.S. Department of the Interior). Estimation is more difficult because of the convolution of parameters between relea se and recovery and this convolution may cause estimates of the surviv al/migration parameters to have low precision. Derived parameters of e migration, immigration, harvest derivation, and overall net survival a re also estimated. The models are applied to estimate the migration of Pacific herring among spawning grounds off the west coast of Canada. If animals can be re-released after being recaptured, the model corres ponds, in its migration/survival components, to that of Arnason (1972, Researches in Population Ecology 13, 97-113). This correspondence is developed, leading to more efficient estimators of these parameters.