A Review of Length-based Approaches to Assessing Fish Stocks

A Review of Length-based Approaches to Assessing Fish Stocks

Author: J. A. Gulland

Publisher: Food & Agriculture Org.

Published: 1992

Total Pages: 112

ISBN-13: 9789251031216

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This document reviews the several fish stock assessment methods based on length-frequency analysis. Emphasis is placed on sampling and collection of length-frequency data, to the estimation of population parameters such as growth, mortality and recruitment and the estimation of catch selectivity. Attention is given to the conversion of length to age using age-length keys, slicing length-frequency composition, and using modes. It reviews long-and short-term effects of changes in selection and fishing mortality, and discusses methods for long-term assessments and for short-term projections. The manual gives several examples of the most common methods used and stresses the advantages of using personal computers and the most recent software for data processing and analysis.