Repeatability of Nest Site Selection of Green Turtles on Samandağ Beach

Abstract

Nest site selection is a maternal effect on hatchling survival in species without parental care. Sea turtles depend on sandy beaches for nesting, and females perform nest site selection on the beach for the successful development of their embryos. This study investigated the repeatability of nest site selection on Samandağ beach, a major green turtle nesting beach in the Mediterranean. During the 2013 nesting season, the distance to the sea, distance to vegetation, horizontal distance, and nest depth of the first and second nests of females were recorded using a tagging method. Repeatability analysis was performed using the rtpR package in R. A total of 91 turtles were tagged, of which 36 were observed during their first and second nests. The highest repeatability was found for horizontal distance, followed by distance to vegetation and distance to the sea. In contrast, nest depth showed insignificant repeatability. This suggests that green turtles select nesting sites that are close to the vegetation line but far from the sea and sites that are very close in horizontal distance. The results of this study include the results of a single year nesting season. It is recommended that future studies be conducted in consecutive years to see the results of repeatability of nest site selection from year to year.

Keywords

• Chelonia mydas
• green turtle
• nest site section
• repeatability
• Samandağ

Samandağ Kumsalında Yeşil Kaplumbağaların Yuva Yeri Seçiminin Tekrarlanabilirliği

Abstract

Yuva yeri seçimi, ebeveyn bakımı olmayan türlerde yavruların hayatta kalması üzerinde maternal bir etkidir. Deniz kaplumbağaları yuva yapmak için kumsallara bağımlıdır ve dişiler embriyolarının başarılı bir şekilde gelişmesi için kumsalda yuva yeri seçimi yaparlar. Bu çalışmada, Akdeniz'de yeşil kaplumbağalar için önemli bir yuvalama kumsalı olan Samandağ kumsalında yuva yeri seçiminin tekrarlanabilirliği araştırılmıştır. 2013 yuvalama sezonu boyunca, dişilerin ilk ve ikinci yuvalarının denize uzaklığı, bitki örtüsüne uzaklığı, yatay mesafesi ve yuva derinliği etiketleme yöntemiyle kaydedilmiştir. Tekrarlanabilirlik analizi R programında rtpR paketi kullanılarak gerçekleştirilmiştir. Toplam 91 kaplumbağa etiketlenmiştir; bu kaplumbağaların 36'sı ilk ve ikinci yuvaları sırasında gözlemlenmiştir. En yüksek tekrarlanabilirlik yatay mesafede bulunmuş, bunu bitki örtüsüne olan mesafe ve denize olan mesafe izlemiştir. Buna karşılık, yuva derinliği önemsiz bir tekrarlanabilirlik göstermiştir. Bu da yeşil kaplumbağaların yuvalama alanı olarak bitki örtüsüne yakın ancak denizden uzak alanları ve yatay mesafe olarak birbirine çok yakın alanları seçtiğini göstermektedir. Bu çalışmanın sonuçları tek bir yıllık yuvalama sezonunun sonuçlarını içermektedir. Yuva yeri seçiminin yıldan yıla tekrarlanabilirliğinin sonuçlarını görmek için gelecekteki çalışmaların birbirini takip eden yıllarda yapılması tavsiye edilir.

Keywords

• Chelonia mydas
• yeşil kaplumbağa
• yuva yeri seçimi
• tekrarlanabilirlik
• Samandağ

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