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Bodies stay warm in cold water: skipjack tuna


Skipjack tuna shoal / NOAA / LicensePD - Public Domain

Bodies of skipjack tuna stay warmer because of counter-current heat exchange system.

"Tunas are extraordinary fishes. This paper concerns one of the features that makes them extraordinary: the counter-current heat exchanger. The evolution of this device permits tuna to achieve body temperatures much greater than ambient water temperature. For example, the muscle temperature of large bluefin tuna can be as much  as 20 °C above ambient water temperature (Carey et al. 1971) and the muscle temperature of small skipjack tuna (2 kg) can be as much as 9 °C above ambient (Stevens & Fry, 1971). The body temperature of other fishes is at most 2 °C above ambient (Stevens & Fry, 1970) because metabolic heat is efficiently transferred from the venous blood to surrounding water at the gills (Fig. 1). To maintain a large temperature excess, tuna have had to make a tremendous anatomical investment and construct a thermal barrier between venous blood and the gills. The present paper describes this thermal barrier, the counter-current heat exchanger of skipjack tuna." (Stevens 1973:145)
About the inspiring organism
Med_skipjack_tuna_shoal Arctic bonito
Katsuwonus pelamis (Linnaeus, 1758)
Common names: Atlantic bonito, Atu, Banjo, Barriolet, Bonito, Club mackerel, Lesser tunny, Mushmouth, Ocean bonito, Oceanic bonito, Oceanic skipjack, Skipjack, Skipjack tuna, Skipjack tuna fish, Skipjack-tuna, Skipper, Skippy, Skiy jack, Striped bellied bonito, Striped

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Some organism data provided by: FishBase
Organism/taxonomy data provided by:
Species 2000 & ITIS Catalogue of Life: 2008 Annual Checklist

Bioinspired products and application ideas

Application Ideas: Thermal barrier for keeping heat energy contained. Exchange systems for transferring heat energy.

Industrial Sector(s) interested in this strategy: Aerospace, Automobile, Energy, Water

Stevens, E. D.; Kanwisher, J. W.; Carey, F. G. 2000. Muscle temperature in free-swimming giant Atlantic bluefin tuna (Thunnus thynnus L.). Journal of Thermal Biology. 25(6): 419-423.
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Stevens, E. Don; Lam, How Man; Kendall, J. 1974. Vascular Anatomy of the Counter-Current Heat Exchanger of Skipjack Tuna. J Exp Biol. 61(1): 145-153.
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Stevens ED; Lam HM; Kendall J. 1974. Vascular anatomy of the counter-current heat exchanger of skipjack tuna. Journal of Experimental Biology. 61(1): 145-153.
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