Archival tagging of a basking shark, Cetorhinus maximus, in the western North Atlantic

A 6·1-m long female basking shark (Cetorhinus maximus) was tagged 73 km east of Nantucket Island, Massachusetts on 27 September 2001 with a pop-up archival transmitting tag. The tag detached prematurely on 6 December 2001 in an area approximately 800 km south-west of the tag site off the coast of North Carolina. The basking shark was vertically active for the 71-d tracking period, moving through depths and temperatures ranging from the surface to 320 m and 5·8 to 21·0°C, respectively. The shark displayed temporal variation in its residence depth and exhibited a marked temperature preference, with 72% of the temperature observations between 15·0 and 17·5°C. This track provides evidence that the basking shark associates with the continental shelf and shelf edge off the south-eastern United States during autumn. Moreover, it corroborates previous studies indicating that the basking shark remains active and does not hibernate during autumn.