Vertical distribution and feeding ecology of a copepod Gaetanus variabilis in the southern Japan Sea during winter

うみ Volume 45 Issue 1 Page 47-58 published_at 2007-02-28
アクセス数 : 749
ダウンロード数 : 164

今月のアクセス数 : 7
今月のダウンロード数 : 2
File
La-mer_45-1_47.pdf 1.53 MB 種類 : fulltext
Title ( eng )
Vertical distribution and feeding ecology of a copepod Gaetanus variabilis in the southern Japan Sea during winter
Title ( jpn )
冬季の日本海南部における中層性かいあし類Gaetanus variabilisの鉛直分布、腸内容物および餌要求量
Creator
Yamaguchi Atsushi
Hirakawa Kazumasa
Ikeda Tsutomu
Source Title
うみ
Volume 45
Issue 1
Start Page 47
End Page 58
Abstract
Vertical distribution, gut fullness and gut contents were investigated on an aetideid copepod Gaetanus variabilis during winter at a station in the southern Japan Sea. Most individuals of C3-C6 (adult) G. variabilis were distributed between 500 and 1000 m depth. While early copepodid stages resided deeper than older ones, no diel vertical migration was detected throughout the copepodid stages. Feeding activity of G. variabilis as judged by gut fullness scores varied with developmental stage/sex, but no diel feeding rhythm was observed. Adult males cease feeding as a reflection of degeneration of their feeding appendages. The gut content analysis showed that G. variabilis is a particle feeder consuming mainly upon silicoflagellates, followed by diatoms, tintinnids and fragments of metazooplankton. An estimated daily ration of G. variabilis population based on calculated metabolic rates was 5.03 mg C m-2 day-1, which accounts for 4.5% of the local primary production or 54% of particulate organic carbon flux down to the 500 m depths at southern Japan Sea.
Keywords
gut content
daily ration
mesopelagic
copepods
Japan Sea
NDC
Zoology [ 480 ]
Language
eng
Resource Type journal article
Publisher
日仏海洋学会
Date of Issued 2007-02-28
Publish Type Version of Record
Access Rights open access
Source Identifier
[ISSN] 0503-1540
[NCID] AN00019968