ESTIMATING MIGRATION RATES FOR PACIFIC HERRING (CLUPEA-PALLASI) USINGTAG-RECOVERY DATA

Tag-recovery data can be used to estimate migration rates among a set of strata provided that both tagging and recoveries occur on all the s trata over a number of years. The model formulation described here is a simple matrix extension of a tag-recovery experiment where individua l recaptures are replaced by a matrix of recoveries representing movem ent between release and recovery sites. Derived parameters of emigrati on, immigration, and overall net survival can also be estimated. The m odels are applied to estimate the migration of Pacific herring (Clupea pallasi) between spawning grounds in the Prince Rupert District and C entral District of British Columbia. Effects of the violation of assum ptions and aspects of the planning of capture-recapture experiments ar e also presented.