Empirical weighting of multiple stock-abundance indices for parameter estimation and stock assessment in a multi-zone or multi-species fishery

In order to make use of all available information, fishery stock assessment researchers often use several indices of stock abundance. These indices ar e derived from commercial, as well as fishery-independent sources. Since th e indices all relate to the same fishery but may differ in the degree of ac curacy with which they reflect stock size, appropriate wrights must be chos en for each. This paper contains an outline of an empirical approach to ass igning index weights via the likelihood function that underpins both classi cal and Bayesian statistical methods. The approach is demonstrated for a st imulated three-zone paua (Haliotis iris) fishery, and can be used readily f ur multi-species fisheries and/or for assessment of multiple-use management of marine resources. (C) 2001 International council for the Exploration of the Sea.