School of Earth, Environmental, & Marine Sciences Faculty Publications
Document Type
Article
Publication Date
2026
Abstract
Hawksbill sea turtles (Eretmochelys imbricata) are listed as critically endangered by the International Union for the Conservation of Nature (IUCN). To implement best conservation practices for this species, its biology should be well understood. Attempting to characterize the foraging physiology of free-ranging hawksbill sea turtles is complicated by the fact that sampling is typically limited to nesting females during the reproductive season. Without data from non-reproductive periods, it is difficult to determine whether observed physiological values reflect baseline conditions or are specific to the energetically demanding nesting season. Accordingly, in this study, we described the physiology of foraging in a captive-held population of hawksbill sea turtles for an entire year. Across the year, we sampled a total of five captive adult female hawksbills at the Okinawa Churaumi Aquarium in Okinawa, Japan. We measured the concentration of β-hydroxybutyrate (BHB), triglycerides (TRGs) and testosterone. Foraging biomarkers BHB and TRGs were both significantly higher during gonadal recrudescence and breeding than during gonadal quiescence, consistent with mature animals that were not foraging actively during breeding activities. Testosterone concentration also was higher during breeding months than during non-breeding months, especially in May, which marked the onset of mating. Elevated BHB during breeding activities indicated that captive hawksbills accumulated energy reserves during the non-breeding season to invest it in breeding activities. Additionally, elevated TRGs are correlated to vitellogenesis occurring in the breeding female hawksbills.
Recommended Citation
Kent, Joslyn Blessing, Kari Renee Dawson, Shingo Fukada, Masae Makabe, Isao Kawazu, Ken Maeda, and Roldán A. Valverde. "Biomarkers of foraging and reproduction in captive adult female hawksbill sea turtles (Eretmochelys imbricata)." Conservation Physiology 14, no. 1 (2026): coag003. https://doi.org/10.1093/conphys/coag003
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 International License.
Publication Title
Conservation Physiology
DOI
10.1093/conphys/coag003
Comments
© The Author(s) 2026. Published by Oxford University Press on behalf of the Society for Experimental Biology. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited.