Abstract

Pacific bluefin tuna (Thunnus orientalis) are highly migratory apex marine predators that inhabit a broad thermal niche. The energy needed for migration must be garnered by foraging, but measuring energy intake in the marine environment is challenging. We quantified the energy intake of Pacific bluefin tuna in the California Current using a laboratory-validated model, the first such measurement in a wild marine predator. Mean daily energy intake was highest off the coast of Baja California, Mexico in summer (mean +/- SD, 1034 +/- 669 kcal), followed by autumn when Pacific bluefin achieve their northernmost range in waters off northern California (944 +/- 579 kcal). Movements were not always consistent with maximizing energy intake: the Pacific bluefin move out of energy rich waters both in late summer and winter, coincident with rising and falling water temperatures, respectively. We hypothesize that temperature-related physiological constraints drive migration and that Pacific bluefin tuna optimize energy intake within a range of optimal aerobic performance.

Published in

Science Advances
2015, Volume: 1, number: 8, article number: e1400270

SLU Authors

• Whitlock, Rebecca

  • Department of Aquatic Resources (SLU Aqua), Swedish University of Agricultural Sciences
    
  • Stanford University

UKÄ Subject classification

Physiology
Fish and Aquacultural Science
Ecology


Publication identifier

DOI: https://doi.org/10.1126/sciadv.1400270

Permanent link to this page (URI)

https://res.slu.se/id/publ/73409