Review and preliminary analyses of conventional tagging data on Atlantic blue shark stocks (Prionace glauca)

Conventional tagging data of North and South Atlantic blue shark stocks were reviewed, and preliminary analyses were performed for its use within the stock evaluation. The tag releases and recapture records were revised, updated, and standardized, to summarize size distributions, time at large and distance displacement between release and recapture locations. Most of the tag releases are in the North Atlantic area, recaptures suggested a low exchange of individuals between current stock management units in the Atlantic and Mediterranean. Size distribution of tag releases and recaptures show unimodal normal distributions with a mean size of 156 and 189 SFL cm, respectively. Time at large showed recaptures up to 15 years at liberty, with a mean of 407 days at large. Stainless steel tag's reporting rates were higher than plastic double-barb streamers. And inferred movement patterns suggest a clockwise migration in the North Atlantic from the easter coast of North America to Europe following the Gulf Stream current and returning southwest to the equatorial region and the Caribbean Sea.