Skip to main content
Article
Influence of Swimming Speed on Metabolic Rates of Juvenile Pacific Bluefin Tuna and Yellowfin Tuna
Physiological and Biochemical Zoology
  • Jason M. Blank, Stanford University
  • Charles J. Farwell, Monterey Bay Aquarium
  • Jeffery M. Morrissette, Stanford University
  • Robert J. Schallert, Monterey Bay Aquarium
  • Barbara A. Block, Stanford University
Publication Date
3-1-2007
Abstract

Bluefin tuna are endothermic and have higher temperatures, heart rates, and cardiac outputs than tropical tuna. We hypothesized that the increased cardiovascular capacity to deliver oxygen in bluefin may be associated with the evolution of higher metabolic rates. This study measured the oxygen consumption of juvenile Pacific bluefin Thunnus orientalis and yellowfin tuna Thunnus albacares swimming in a swim-tunnel respirometer at 20°C. Oxygen consumption ( Mo2) of bluefin (7.1–9.4 kg) ranged from 235 ± 38 mg kg-1 h-1 at 0.85 body length (BL) s-1 to 498 ± 55 mg kg-1 h-1 at 1.80 BL s-1. Minimal metabolic rates of swimming bluefin were 222 ± 24 mg O2 kg-1 h-1 at speeds of 0.75 to 1.0 BL s-1. Mo2 of T. albacares (3.7–7.4 kg) ranged from 164 ± 18 mg kg-1 at 0.65 BL s-1 to 405 ± 105 mg kg-1 h-1 at 1.8 BL s-1. Bluefin tuna had higher metabolic rates than yellowfin tuna at all swimming speeds tested. At a given speed, bluefin had higher metabolic rates and swam with higher tailbeat frequencies and shorter stride lengths than yellowfin. The higher Mo2 recorded in Pacific bluefin tuna is consistent with the elevated cardiac performance and enhanced capacity for excitation-contraction coupling in cardiac myocytes of these fish. These physiological traits may underlie thermal-niche expansion of bluefin tuna relative to tropical tuna species.

Disciplines
Citation Information
Jason M. Blank, Charles J. Farwell, Jeffery M. Morrissette, Robert J. Schallert, et al.. "Influence of Swimming Speed on Metabolic Rates of Juvenile Pacific Bluefin Tuna and Yellowfin Tuna" Physiological and Biochemical Zoology Vol. 80 Iss. 2 (2007) p. 167 - 177
Available at: http://works.bepress.com/jmblank/2/