Dataset Information

Time in tortoiseshell: a bomb radiocarbon-validated chronology in sea turtle scutes.

ABSTRACT: Some of the most basic questions of sea turtle life history are also the most elusive. Many uncertainties surround lifespan, growth rates, maturity and spatial structure, yet these are critical factors in assessing population status. Here we examine the keratinized hard tissues of the hawksbill (Eretmochelys imbricata) carapace and use bomb radiocarbon dating to estimate growth and maturity. Scutes have an established dietary record, yet the large keratin deposits of hawksbills evoke a reliable chronology. We sectioned, polished and imaged posterior marginal scutes from 36 individual hawksbills representing all life stages, several Pacific populations and spanning eight decades. We counted the apparent growth lines, microsampled along growth contours and calibrated ?(14)C values to reference coral series. We fit von Bertalanffy growth function (VBGF) models to the results, producing a range of age estimates for each turtle. We find Hawaii hawksbills deposit eight growth lines annually (range 5-14), with model ensembles producing a somatic growth parameter (k) of 0.13 (range 0.1-0.2) and first breeding at 29 years (range 23-36). Recent bomb radiocarbon values also suggest declining trophic status. Together, our results may reflect long-term changes in the benthic community structure of Hawaii reefs, and possibly shed light on the critical population status for Hawaii hawksbills.

SUBMITTER: Van Houtan KS

PROVIDER: S-EPMC4721088 | biostudies-literature | 2016 Jan

REPOSITORIES: biostudies-literature

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Publications

Time in tortoiseshell: a bomb radiocarbon-validated chronology in sea turtle scutes.

Van Houtan Kyle S KS Andrews Allen H AH Jones T Todd TT Murakawa Shawn K K SK Hagemann Molly E ME

Proceedings. Biological sciences 20160101 1822

Some of the most basic questions of sea turtle life history are also the most elusive. Many uncertainties surround lifespan, growth rates, maturity and spatial structure, yet these are critical factors in assessing population status. Here we examine the keratinized hard tissues of the hawksbill (Eretmochelys imbricata) carapace and use bomb radiocarbon dating to estimate growth and maturity. Scutes have an established dietary record, yet the large keratin deposits of hawksbills evoke a reliable ...[more]

PMID: 26740617

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Dataset Information

Time in tortoiseshell: a bomb radiocarbon-validated chronology in sea turtle scutes.

Publications

Time in tortoiseshell: a bomb radiocarbon-validated chronology in sea turtle scutes.

Similar Datasets

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