Factors affecting hatch success of hawksbill sea turtles on Long Island, Antigua, West Indies.

Current understanding of the factors influencing hawksbill sea turtle (Eretmochelys imbricata) hatch success is disparate and based on relatively short-term studies or limited sample sizes. Because global populations of hawksbills are heavily depleted, evaluating the parameters that impact hatch suc...

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Main Authors: Mark Allan Ditmer, Seth Patrick Stapleton
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2012-01-01
Series:PLoS ONE
Online Access:http://europepmc.org/articles/PMC3389013?pdf=render
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author Mark Allan Ditmer
Seth Patrick Stapleton
author_facet Mark Allan Ditmer
Seth Patrick Stapleton
author_sort Mark Allan Ditmer
collection DOAJ
description Current understanding of the factors influencing hawksbill sea turtle (Eretmochelys imbricata) hatch success is disparate and based on relatively short-term studies or limited sample sizes. Because global populations of hawksbills are heavily depleted, evaluating the parameters that impact hatch success is important to their conservation and recovery. Here, we use data collected by the Jumby Bay Hawksbill Project (JBHP) to investigate hatch success. The JBHP implements saturation tagging protocols to study a hawksbill rookery in Antigua, West Indies. Habitat data, which reflect the varied nesting beaches, are collected at egg deposition, and nest contents are exhumed and categorized post-emergence. We analyzed hatch success using mixed-model analyses with explanatory and predictive datasets. We incorporated a random effect for turtle identity and evaluated environmental, temporal and individual-based reproductive variables. Hatch success averaged 78.6% (SD: 21.2%) during the study period. Highly supported models included multiple covariates, including distance to vegetation, deposition date, individual intra-seasonal nest number, clutch size, organic content, and sand grain size. Nests located in open sand were predicted to produce 10.4 more viable hatchlings per clutch than nests located >1.5 m into vegetation. For an individual first nesting in early July, the fourth nest of the season yielded 13.2 more viable hatchlings than the initial clutch. Generalized beach section and inter-annual variation were also supported in our explanatory dataset, suggesting that gaps remain in our understanding of hatch success. Our findings illustrate that evaluating hatch success is a complex process, involving multiple environmental and individual variables. Although distance to vegetation and hatch success were inversely related, vegetation is an important component of hawksbill nesting habitat, and a more complete assessment of the impacts of specific vegetation types on hatch success and hatchling sex ratios is needed. Future research should explore the roles of sand structure, nest moisture, and local weather conditions.
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spelling doaj.art-070de2e0778b4d91b1bc843cf5a0fd6e2022-12-22T00:16:33ZengPublic Library of Science (PLoS)PLoS ONE1932-62032012-01-0177e3847210.1371/journal.pone.0038472Factors affecting hatch success of hawksbill sea turtles on Long Island, Antigua, West Indies.Mark Allan DitmerSeth Patrick StapletonCurrent understanding of the factors influencing hawksbill sea turtle (Eretmochelys imbricata) hatch success is disparate and based on relatively short-term studies or limited sample sizes. Because global populations of hawksbills are heavily depleted, evaluating the parameters that impact hatch success is important to their conservation and recovery. Here, we use data collected by the Jumby Bay Hawksbill Project (JBHP) to investigate hatch success. The JBHP implements saturation tagging protocols to study a hawksbill rookery in Antigua, West Indies. Habitat data, which reflect the varied nesting beaches, are collected at egg deposition, and nest contents are exhumed and categorized post-emergence. We analyzed hatch success using mixed-model analyses with explanatory and predictive datasets. We incorporated a random effect for turtle identity and evaluated environmental, temporal and individual-based reproductive variables. Hatch success averaged 78.6% (SD: 21.2%) during the study period. Highly supported models included multiple covariates, including distance to vegetation, deposition date, individual intra-seasonal nest number, clutch size, organic content, and sand grain size. Nests located in open sand were predicted to produce 10.4 more viable hatchlings per clutch than nests located >1.5 m into vegetation. For an individual first nesting in early July, the fourth nest of the season yielded 13.2 more viable hatchlings than the initial clutch. Generalized beach section and inter-annual variation were also supported in our explanatory dataset, suggesting that gaps remain in our understanding of hatch success. Our findings illustrate that evaluating hatch success is a complex process, involving multiple environmental and individual variables. Although distance to vegetation and hatch success were inversely related, vegetation is an important component of hawksbill nesting habitat, and a more complete assessment of the impacts of specific vegetation types on hatch success and hatchling sex ratios is needed. Future research should explore the roles of sand structure, nest moisture, and local weather conditions.http://europepmc.org/articles/PMC3389013?pdf=render
spellingShingle Mark Allan Ditmer
Seth Patrick Stapleton
Factors affecting hatch success of hawksbill sea turtles on Long Island, Antigua, West Indies.
PLoS ONE
title Factors affecting hatch success of hawksbill sea turtles on Long Island, Antigua, West Indies.
title_full Factors affecting hatch success of hawksbill sea turtles on Long Island, Antigua, West Indies.
title_fullStr Factors affecting hatch success of hawksbill sea turtles on Long Island, Antigua, West Indies.
title_full_unstemmed Factors affecting hatch success of hawksbill sea turtles on Long Island, Antigua, West Indies.
title_short Factors affecting hatch success of hawksbill sea turtles on Long Island, Antigua, West Indies.
title_sort factors affecting hatch success of hawksbill sea turtles on long island antigua west indies
url http://europepmc.org/articles/PMC3389013?pdf=render
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