Marine Biology

, Volume 137, Issue 2, pp 347–358

Tracking adult North Atlantic bluefin tuna (Thunnus thynnus) in the northwestern Atlantic using ultrasonic telemetry

Authors

  • M. E. Lutcavage
    • Edgerton Research Laboratory, New England Aquarium, Central Wharf, Boston, Massachusetts 02110, USA e-mail: mlutcavg@neaq.org Tel.: +1-617-9735451 Fax: +1-617-7239705
  • R. W. Brill
    • Pelagic Fisheries Research Program, Joint Institute for Marine and Atmospheric Research, School of Earth Science and Technology, University of Hawaii at Manoa, Honolulu, Hawaii 86822, USA
  • G. B. Skomal
    • Massachusetts Division of Marine Fisheries, P.O. Box 68, Vineyard Haven, Massachusetts 02568, USA
  • B. C. Chase
    • Massachusetts Division of Marine Fisheries, 30 Emerson Avenue, Gloucester, Massachusetts 01930, USA
  • J. L. Goldstein
    • Edgerton Research Laboratory, New England Aquarium, Central Wharf, Boston, Massachusetts 02110, USA e-mail: mlutcavg@neaq.org Tel.: +1-617-9735451 Fax: +1-617-7239705
  • J. Tutein
    • 1 Rear Frank Street, Rockport, Massachusetts 01966, USA

DOI: 10.1007/s002270000302

Cite this article as:
Lutcavage, M., Brill, R., Skomal, G. et al. Marine Biology (2000) 137: 347. doi:10.1007/s002270000302

Abstract

Ultrasonic, depth-sensitive transmitters were used to track the horizontal and vertical movements, for up to 48 h, of 11 adult (136 to 340 kg estimated body mass) North Atlantic bluefin tuna (Thunnus thynnus Linnaeus). Fish were tracked in October 1995, September and October 1996, and August and September 1997 in the Gulf of Maine, northwestern Atlantic. The objective was to document the behavior of these fish and their schools in order to provide the spatial, temporal, and environmental information required for direct (i.e. fishery-independent) assessment of adult bluefin tuna abundance using aerial surveys. Transmitters were attached to free-swimming fish using a harpoon attachment technique, and all fish remained within the Gulf of Maine while being followed. Most of the bluefin tuna tagged on Stellwagen Bank or in Cape Cod Bay (and followed for at least 30 h) held a predominately easterly course with net horizontal displacements of up to 76 km d−1. Mean (±SD) swimming depth for all fish was 14 ± 4.7 m and maximum depth for individuals ranged from 22 to 215 m. All but one fish made their deepest excursions, often single descents, at dawn and dusk. In general, adult bluefin tuna spent <8% of their time at the surface (0 to 1 m), <19% in the top 4 m, but >90% in the uppermost 30 m. Mean (±SD) speed over ground was 5.9 km h−1, but for brief periods surpassed 20 to 31 km h−1. Sea surface temperatures during tracking were 11.5 to 22.0 °C, and minimum temperatures encountered by the fish ranged from 6.0 to 9.0 °C. Tagged bluefin tuna and their schools frequented ocean fronts marked by mixed vertebrate feeding assemblages, which included sea birds, baleen whales, basking sharks, and other bluefin schools.

Copyright information

© Springer-Verlag Berlin Heidelberg 2000