Diversity of larval tuna diets across the central equatorial Pacific

Understanding the feeding ecology of larval tuna is essential for predicting their recruitment and survival success as this directly supports the management of tuna populations across the changing ocean. To provide new insights into early-stage foraging dynamics, we investigated larval tuna gut contents collected from the Phoenix Islands Protected Area (PIPA) during its no-take period between 2016 and 2019. Using 18S sequencing, we characterized prey biodiversity, composition, and selectivity across years and tuna genera. We found that larval tunas consumed a taxonomically diverse range of zooplankton, with Katsuwonus exhibiting opportunistic foraging characterized by one or two dominant prey taxa that shifted across years, while Thunnus, despite limited sampling– consumed a broader range of prey taxa within a given year. Prey composition and selectivity varied by year and tuna genus, reflecting possible responses to shifting plankton communities and environmental conditions such as the ENSO state, as well as highlighting genus-specific trophic strategies and the potential for niche partitioning that may reduce interspecific competition for prey between tunas. This study sheds light on the ecological flexibility of larval tuna and underscores the importance of considering early-life foraging behavior in efforts to conserve and sustainably manage tuna stocks in the Western and Central Pacific Ocean, particularly in the context of marine protected areas (MPAs) and no-take zones.

Author dc:creator

• Kim, Sunmin

Advisor dc:contributor.advisor

• Rotjan, Randi D.

• Biology
• Feeding ecology
• Larval tuna
• Marine biology

Language dc:language.iso

en_US

Handle dc:identifier.uri

https://hdl.handle.net/2144/51546

OAI identifier oai:identifier

oai:open.bu.edu:2144/51546