Abstract
Local availability of yellowfin tuna, Thunnus albacares, is a key economic, dietary and cultural concern for Main Hawaiian Islands (MHI) communities and insular fisheries. Consequently, interactions of inshore versus offshore fisheries and connectivity to yellowfin elsewhere in the Pacific remain important scientific management questions. Local fisheries target adult tuna during the summer months, but subsequent tuna movements, presumably away from the islands after reproduction ceases, remain undocumented. From 2014-2016, we partnered with local fishermen to catch and release nineteen yellowfin tuna (41- 91 kg, estimated whole weight) off Kauaʻi, with popup satellite archival tags programmed for 9 to 12-month missions. Although data collection periods did not exceed 59 days mainly because of tag hardware failures and predator interactions, short tracks revealed diverse patterns: local residency for some individuals, and rapid, long-distance (>800 km) dispersals in multiple directions for others. Adult yellowfin tuna frequenting the MHI have more complex movements than previously assumed. Despite being a nursery area, whether the assemblage is entirely produced and retained in the region is not resolved. However, attaining one-year migration records requires tag performance that was not achieved by the deployed tags. It remains a prerequisite for greater understanding of yellowfin in the Main Hawaiian Islands and Central North Pacific, including assessment of their spatial connectivity, impacts of climate change, and shifting ecosystems.
Highlights
Yellowfin tuna (Thunnus albacares) is an iconic species in the Main Hawaiian Islands (MHI), yet little is known about where these tuna go after leaving local waters, their daily habits, and whether they inhabit the Islands exclusively, or journey to other areas of the Pacific
Given the importance of the adult spawning assemblage throughout the Hawaiian archipelago, this study aims to delineate the extent of movements and behavior of adult yellowfin tuna in relation to local fisheries, establish potential connectivity to other parts of the Pacific, and provide a much needed update on dispersal patterns in times of changing climate and ecosystems
Yellowfin tuna comprise an enormous part of the economy, diet and culture throughout the Pacific Islands, yet fisheries research and tagging programs have focused intensively on equatorial regions while other parts of the Pacific remain understudied
Summary
Yellowfin tuna (Thunnus albacares) is an iconic species in the Main Hawaiian Islands (MHI), yet little is known about where these tuna go after leaving local waters, their daily habits, and whether they inhabit the Islands exclusively, or journey to other areas of the Pacific. Known locally as ‘ahi, yellowfin tuna have been fished since Polynesians arrived in the Central North Pacific, and remain a prime resource for community stakeholders (Yuen, 1979; Glazier, 2007). Around the MHI, large yellowfin are targeted for fresh fish and sashimi markets, and smaller tuna are important to households and families with limited income (Glazier, 2007). Inshore small-scale troll and handline fisheries directly target yellowfin, with a minimum commercial size limit at 1.36 kg (3 lb) set by the State of Hawai‘i. Apart from a small number of long-distance conventional tag recoveries off Japan and Mexico (Itano and Holland, 2000a), MHI yellowfin were assumed to stay within the islands, e.g., median individual range of
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
