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Patterns in the emergence of green (Chelonia mydas) and loggerhead (Caretta caretta) turtle hatchlings from their nests

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The emergence patterns of both green (Chelonia mydas) and loggerhead (Caretta caretta) turtle hatchlings were observed in great detail over three seasons at Alagadi beach, northern Cyprus. In total, 38 green turtle and 50 loggerhead turtle nests were monitored, accounting for the emergence of 2,807 and 2,259 hatchlings, respectively. We quantified these emergences into 397 green turtle and 302 loggerhead turtle emergence groups. Overall, 85.0% of green turtle and 79.5% of loggerhead turtle groups emerged at night; these accounted for 85.5 and 90.8% of hatchlings, respectively. The remaining emergences were dispersed throughout the day for green turtle nests but confined to the morning in loggerhead turtle nests. Hatchling emergence from individual nests occurred over periods of between 1 and 7 nights, with most hatchlings typically emerging on the first night. Group sizes of green turtles emerging during the day were significantly smaller than those emerging at night. Hatchlings of both species that emerged from nests during the day had longer emergence durations than those that emerged from nests at night only.

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We thank all the members of the Marine Turtle Conservation Project, the Department of Environmental Protection, and the Society for the Protection of Turtles in Northern Cyprus. This work was undertaken as part of expeditions supported by British Chelonia Group, British Ecological Society, European Commission (DG1B/1A), Kibris Turkish Airlines, MEDASSET UK, People’s Trust for Endangered Species. BG is supported by an NERC fellowship. ACB is supported by a grant from the FCO Environment fund for the Overseas Territories. The experiments comply with the current laws of the country in which they were performed. The manuscript was improved by the constructive review of two anonymous referees.

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Correspondence to F. Glen.

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Communicated by R.J. Thompson, St. John’s

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Glen, F., Broderick, A.C., Godley, B.J. et al. Patterns in the emergence of green (Chelonia mydas) and loggerhead (Caretta caretta) turtle hatchlings from their nests. Marine Biology 146, 1039–1049 (2005).

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