Vertical and Horizontal Movements of Yellowfin Tuna in the Gulf of Mexico

J P Hoolihan,E D Prince,R J D Wells,J Luo,J R Rooker,B Falterman

doi:10.1080/19425120.2014.935900

Abstract

AbstractPop‐up satellite archival tags (n = 31) were deployed on Yellowfin Tuna Thunnus albacares in the Gulf of Mexico for periods ranging from 14 to 95 d. Differences in diel vertical behavior were assessed by comparing time spent at temperature relative to the surface temperature (ΔT). Pooled samples revealed that 31% of darkness hours, 20% of twilight hours, and 12% of daylight hours were spent in the uniform‐temperature surface layer (i.e., ΔT = 0). Total time spent above 100 m was less during daylight (90.0%) than during darkness (99.8%), suggesting greater exploration of deeper depths during daylight hours. Maximum depth visited ranged from 208 to 984 m, and minimum temperature visited ranged from 5.4°C to 11.8°C. Only a small proportion of total time was spent at temperatures colder than 8°C below the surface temperature. Horizontal excursions for the majority of individuals were less than 100 km from the point of release; however, three individuals moved distances of 411–1,124 km, suggesting that this species has the capability to move relatively long distances within the Gulf of Mexico. The ΔT values are provided in tabular format and serve as direct input variables for use in habitat standardization models.Received January 7, 2014; accepted June 8, 2014

Highlights

Pop-up satellite archival tags (n = 31) were deployed on Yellowfin Tuna Thunnus albacares in the Gulf of Mexico for periods ranging from 14 to 95 d
We examined data that were collected from Pop-up satellite archival tags (PSATs) deployed on Yellowfin Tuna (n = 31) in the northern Gulf of Mexico (GOM) during 2008–2011
Each time block included (1) the proportion of time spent within each depth bin (25-m resolution); (2) the proportion of time spent within each temperature bin (2◦C bin resolution); and (3) PSAT depth–temperature (PDT) profile messages

Summary

Introduction

Major input variables for the model include the proportions of time spent within each degree of water temperature relative to the surface temperature ( T); T is a major environmental factor governing the vertical habitat preference (i.e., depth distribution) of tunas and tuna-like species (Hinton and Nakano 1996; Brill and Lutcavage 2001; Goodyear et al 2008; Hoolihan et al 2011b). The objective of this study was to deploy PSATs on Yellowfin Tuna in the Gulf of Mexico (GOM) to (1) investigate horizontal and vertical movement behavior and (2) compile detailed habitat use information that can be applied to spatiotemporal distributions and relative abundance estimations using habitat standardization modeling

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Conclusion