Biologging to identify nesting and non-nesting emergences for four species of imperiled sea turtles

Kristen Hart; Connor F. White; Donna J. Shaver; Margaret Lamont; Michael Cherkiss; Andrew G. Crowder; Nicholas M. Whitney

doi:10.3389/fmars.2025.1691053

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Biologging to identify nesting and non-nesting emergences for four species of imperiled sea turtles

Kristen Hart·Connor F. White·Donna J. Shaver·Margaret Lamont·Michael Cherkiss·Andrew G. Crowder·Nicholas M. Whitney

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Abstract

Quantifying sea turtle nesting behavior is essential for recovery planning and evaluating management actions. Traditional monitoring approaches, based on nest counts from beach surveys, can misclassify non-nesting emergences, obscure true fecundity, and underestimate clutch frequency, metrics that directly influence population models and regulatory decisions. Here, we demonstrate that high-resolution acceleration data loggers (ADLs) can reliably discriminate nesting from non-nesting emergences across four imperiled species of sea turtles at sites in the Gulf of America, southeast USA, and Caribbean. From 60 recovered ADL deployments on green ( Chelonia mydas ; N = 10), hawksbill ( Eretmochelys imbricata ; N = 7), Kemp’s ridley ( Lepidochelys kempii ; N = 21), and loggerhead sea turtles ( Caretta caretta ; N = 22) lasting on average 17.5 ± 8.7 days (range 2–43 days), we identified 54 nesting events and 76 non-nesting emergences, with >97% accuracy when compared to direct observations. These data provide the first observer-validated, species-specific behavioral signatures of nesting phases and reveal correlations between egg-laying duration and clutch size. All non-nesting emergences occurred within 72 hours of subsequent nesting, allowing managers to anticipate nest deposition windows. By refining inter-nesting intervals and fecundity estimates, ADLs offer a practical path to reduce error in clutch frequency estimates. The integration of ADL-derived algorithms with satellite-transmitting tags would enable the remote, real-time monitoring of nesting activity, creating a system for the remote monitoring of inter-nesting intervals and nest fecundity that are crucial to quantify the impacts of climate change and other threats to sea turtle nesting habitat.

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Source-reported bounding extent: 17° to 35° latitude; -100° to -60° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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BibTeX RIS

Kristen Hart, Connor F. White, Donna J. Shaver, Margaret Lamont, Michael Cherkiss, Andrew G. Crowder, Nicholas M. Whitney. 2025-12-05. Biologging to identify nesting and non-nesting emergences for four species of imperiled sea turtles. https://doi.org/10.3389/fmars.2025.1691053

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