open access

https://hdl.handle.net/2115/35568

Diel rhythms of oxygen consumption and activity level of juvenile flownder Paralichthys olivaceus

英語

activity

1997

The Japanese Society of Scientific Fisheries

Fisheries science

63(5)

655-658

The diel rhythms of oxygen consumption and activity level were measured over a 24-hr period in three size groups of starved juvenile flounder Paralichthys olivaceus by continuous-flow respiratory and video-observation analysis, respectively. In the small group (mean body weight ± SD, MBW: 3.3±0.9g), two peaks of oxygen consumption were observed at 03:00 and 17:00 hours, and the hourly metabolic rates were not significantly different between dark and light periods. In the medium group (MBW: 20.3±3.7g) and the large group (MBW: 58.5±7.1g), only a single peak was observed at 04:00 or 06:00 hours, and the hourly consumption rates were significantly higher in the dark than in the light. For all groups, the highest oxygen consumption rates occurred under conditions of weak light or darkness. The routine metabolic rate is described by the equation logM=0.643 log W -0.387, where M is the oxygen consumption rate (mgO2/kg/hr) and W is body weigh (kg) at 20°C. The diel pattern in activity rate (duration of swimming per hour in minutes) was similar to the pattern of oxygen consumption; fishes were more active during the night (mean activity rate=5.0min/hr) than duringthe day (mean activity rate=2.2min/hr). The relation between rate of oxygen consumption and activity rate is discussed.

学術雑誌論文

Version of Record

© 1997 The Japanese Society of Fisheries Science

0919-9268

AA10993718