Spatial dynamics of swordfish in the south Pacific Ocean inferred from tagging data

The stock structure and movement patterns of broadbill swordfish (Xiphias gladius) in the south Pacific Ocean are uncertain and potentially have important implications for assessment and management. The most recent stock assessment for swordfish within the Western and Central Pacific Ocean (WCPO) was conducted in 2008.Since then, an expanded electronic tagging dataset has become available, and although still limited by small sample sizes, short periods at liberty and infrequent location information, provides evidence for revising spatial assumptions used in the 2008 assessment. Temperate eastern parts of the southwest Pacific appear to be linked to the tropical eastern part of the south-central Pacific, indicating that these areas should no longer be considered separately. Other assumptions from the 2008 assessment are supported, including: (i) no mixing between the southern and northern WCPO, (ii) no mixing between the WCPO and the eastern Pacific Ocean, and (iii) limited connectivity between the eastern and western parts of the Tasman and Coral Seas. Approximate movement rate estimates are provided which may be relevant for future stock assessmentsVersión de editor