Stock Identification Methods
Stock Identification Methods

Author: Lisa A. Kerr

Publisher: Elsevier

Published: 2004-10-15

Total Pages: 735

ISBN-13: 0080470432

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Stock Identification Methods provides a comprehensive review of the various disciplines used to study the population structure of fishery resources. It represents the worldwide experience and perspectives of experts on each method, assembled through a working group of the International Council for the Exploration of the Sea. The book is organized to foster interdisciplinary analyses and conclusions about stock structure, a crucial topic for fishery science and management. Technological advances have promoted the development of stock identification methods in many directions, resulting in a confusing variety of approaches. Based on central tenets of population biology and management needs, Stock Identification Methods offers a unified framework for understanding stock structure by promoting an understanding of the relative merits and sensitivities of each approach.* Describes eighteen distinct approaches to stock identification grouped into sections on life history traits, environmental signals, genetic analyses, and applied marks* Features experts' reviews of benchmark case studies, general protocols, and the strengths and weaknesses of each identification method* Reviews statistical techniques for exploring stock patterns, testing for differences among putative stocks, stock discrimination, and stock composition analysis* Focuses on the challenges of interpreting data and managing mixed-stock fisheries

The Dynamics of Tuna Movements
The Dynamics of Tuna Movements

Author: John R. Hunter

Publisher: Food & Agriculture Org.

Published: 1986

Total Pages: 88

ISBN-13: 9789251024713

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Weaknesses in understanding of tuna distributions and movements have constrained the development of rational management policies. Uncertainties exist in: the selection of management plans and catch and effort data that are representative of a stock; quantification of exchange of adults among management jurisdictions and fishing gears; and identification of the relationships between the environment and tuna movements. This report summarizes a series of discussions between a panel and groups of experts on how to increase understanding of these and other tuna problems. We discuss the uncertainties in current management policy caused by lack of understanding of tuna movement dynamics. We describe and evaluate the research approaches presently used to describe the movements of tunas--mark and recapture and acoustic tracking-- and those which might be used or are just being applied, including new tagging systems, measurement of physiological state and microconstituents of mineralized tissue. Actions needed to improve the knowledge of tuna movements are: 1) establish international arrangements to share tuna movement data, to analyse movements on an oceanwide and worldwide basis and to link international oceanographic programs; 2) increase number and kinds of observations of movements of tuna in the vertical plane; 3) develop and use technology for tracing the actual paths followed by tunas over extended periods and for measuring movements independent of the fishery; and 4) conduct intensive studies on tuna movement dynamics which combine old with the new technologies discussed in the report.