Comparison of the swimming ability and upstream-migration behavior between chum salmon and masu salmon
2013; Canadian Science Publishing; Volume: 71; Issue: 2 Linguagem: Inglês
10.1139/cjfas-2013-0480
ISSN1205-7533
AutoresKoji MIYOSHI, Kazufumi Hayashida, Taku Sakashita, Makoto Fujii, Hisaya Nii, Katsuya Nakao, Hiroshi Ueda,
Tópico(s)Marine and fisheries research
ResumoThe spawning ground of chum salmon (Oncorhynchus keta) is usually located farther downriver than that of masu salmon (Oncorhynchus masou) in Hokkaido, Japan. To compare the swimming abilities of these two species, the relationship between swimming speed and oxygen consumption was compared using a swim tunnel in the laboratory. Then, the upstream-migration behaviors of chum salmon and masu salmon were compared using electromyogram telemetry at fish passages in the Toyohira River, Hokkaido. In the laboratory study, the standard metabolic rate of masu salmon was lower and the critical swimming speed (U crit ) was faster than those of chum salmon. In the field study, the holding time needed to recover the swimming performance exceeding U crit at the fish passages and the trial number needed to pass the fish passages were significantly lower for masu salmon than chum salmon. These results revealed that masu salmon are more adaptable to extended swimming in high water velocity conditions than chum salmon and that masu salmon are better equipped for a long distance upstream migration to their spawning ground than chum salmon.
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