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Vol. 46 No. 6, 2007
Geographical Distribution and Abundance of Pacific Saury,
Cololabis saira (Brevoort) (Scomberesocidae), Fishing Stocks in the
Northwestern Pacific in Relation to Sea Temperatures
Wen-Bin
Huang1,*, Nancy C.H. Lo2, Tai-Sheng Chiu3, and Chih-Shin Chen4
1Graduate
Institute of Biological Resources and Technology, National Hualien
University of Education, Hualien 970, Taiwan
2Southwest Fisheries Science Center, National Marine
Fisheries Service, National Oceanic and Atmospheric Administration, La
Jolla, CA 92037, USA
3Institute of Zoology, National Taiwan University,
Taipei 106, Taiwan
4Institute of Fishery Biology, National Taiwan
University, Taipei 106, Taiwan
Wen-Bin
Huang, Nancy C.H. Lo, Tai-Sheng Chiu, and Chih-Shin Chen (2007)
We compared geographical distributions of Pacific saury, Cololabis
saira
(Brevoort) (Scomberesocidae), fishing stocks in the Northwest
Pacific (NWP) for 3 yearly groups of high, average, and low abundances,
using the Taiwanese fishery catch per unit effort (CPUE) data from 1994
to 2002. Two migratory groups, inshore and offshore, were found in
averageand low-abundance years, while an additional oceanic migratory
group, which spread eastward to around 178°E in Oct., was found in the
year of high abundance. Most of the saury groups were distributed in
areas where the sea surface temperature (SST) ranged between 10 and
20°C with a high aggregation around 15°C, implying that 15°C is the
preferred temperature for saury to aggregate intensively for the
commencement of the spawning migration, and to move southward to
spawning grounds where SSTs of around 20°C are favorable to their
offspring. The timing, abundance, and geographical distributions of
fish aggregations of migratory saury were associated with SSTs. In the
early stages of the fishing season, apparent warming caused by the
intrusion of Kuroshio Current waters in the southern NWP was closely
related to delayed aggregation and low abundances of the saury stock;
in contrast, cooling of the waters affected by Oyashio waters was
related to eastward aggregation and high abundances of saury. High
saury abundances occurred in low-temperature areas. Specifically, in
years of low CPUE values, sea water temperatures (SWTs) of the fishing
grounds were higher than 15°C, while in years of average and high CPUE
values, the SWTs of the fishing grounds were < 15°C. Therefore,
fishing ground SWTs higher than 15°C (around 16°C SST) is an indicator
of low stock abundances of saury in the NWP.
Key words: Geographical
information system, Sea surface temperature, Cololabis saira, Fishing
ground, Taiwan.
*Correspondence: Tel: 886-3-8227106 ext. 2261. Fax:
886-3-8236935. E-mail:bruce@mail.nhlue.edu.tw
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