English  |  正體中文  |  简体中文  |  Items with full text/Total items : 28588/40619
Visitors : 4112047      Online Users : 64
RC Version 4.0 © Powered By DSPACE, MIT. Enhanced by NTU Library IR team.
Scope Adv. Search

Please use this identifier to cite or link to this item: http://ntour.ntou.edu.tw:8080/ir/handle/987654321/44594

Title: Movement patterns determine the availability of Argentine shortfin squid Illex argentinus to fisheries
Authors: Tsan-YuChiu;Tai-ShengChiu;Chih-ShinChen
Contributors: 國立臺灣海洋大學:海洋事務與資源管理研究所
Keywords: Abundance;Migration;GAM;Cross-correlation;Spectral analysis
Date: 2017-09
Issue Date: 2017-11-23T03:05:39Z
Publisher: Fisheries Research
Abstract: Abstract:In this study, we found that dynamic movements of squid in its feeding phase have profound effects on its abundance and thus affect its availability to fisheries. The Argentine shortfin squid Illex argentinus is one of the world’s important economic invertebrate species, with annual fisheries production exceeding one million tons in some years, but the value drastically fluctuates by more than 20-fold. Using catch per unit effort (CPUE) data from the Taiwanese squid jigging fleets during the years 2004–2013, we evaluated its variability in abundance, and the most possible relationships to migration patterns. Results from the statistical analysis using a generalized additive model (GAM) showed that within a specific year, the CPUE was linearly related to latitude (between 46°S and 50°S) and sea surface temperature (SST; of between 10 and 14 °C) components, corresponding to the squid’s dynamic movement during a fishing season. Two distinctive movement patterns for low- and high-abundance years were recognized. In low-abundance years (2004 and 2010), negative cross-correlations between the CPUE and the latitudinal component of the fishing position were found in a time-lagged analyses, suggesting a decoupling of the CPUE from latitude; while in high-abundance years (2007 and 2013), a positive correlation was found, signifying a strong coupling between the CPUE and latitude. A spectral analysis identified one significant long-period (low frequency) coherency between the CPUE and the latitudinal component in 2007, while no significant coherency was found in 2004, suggesting a feasible matchup of squid abundance and its southern feeding movement for an expected high annual production.
Relation: 193 pp.71-80
URI: http://ntour.ntou.edu.tw:8080/ir/handle/987654321/44594
Appears in Collections:[海洋事務與資源管理研究所] 期刊論文

Files in This Item:

There are no files associated with this item.

All items in NTOUR are protected by copyright, with all rights reserved.


著作權政策宣告: 本網站之內容為國立臺灣海洋大學所收錄之機構典藏,無償提供學術研究與公眾教育等公益性使用,請合理使用本網站之內容,以尊重著作權人之權益。
網站維護: 海大圖資處 圖書系統組
DSpace Software Copyright © 2002-2004  MIT &  Hewlett-Packard  /   Enhanced by   NTU Library IR team Copyright ©   - Feedback