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Godo, O. R., Karp, W. A., and Totland, A. 1998. EVects of trawl sampling variability on precision of acoustic abundance estimates of gadoids from the Barents Sea and the Gulf of Alaska. ‐ ICES Journal of Marine Science, 55: 86‐94. The quality of acoustic estimates of fish abundance is dependent on the quality of the biological information that provides the basis for determining target size, species composition and acoustic target strength distribution. Information on biological characteristics of acoustic targets is usually obtained from trawl samples. In this paper we analyse the eVects of trawl sampling variability on estimates of gadoid stock abundance in two areas where behavioural characeristics of the target species diVer. The analyses demonstrate the sensitivity of abundance estimates to trawl sampling. Improved procedures for allocation of trawl sample information to acoustic survey results are discussed. ? 1998 International Council for the Exploration of the Sea |
