Sex determination of green sea turtle (Chelonia mydas) hatchling on the bases of morphological characters)

Sex determination of green sea turtle (Chelonia mydas) hatchlings on the bases of morphological characters

Bektaş Sönmez, Cemal Turan, Şükran Yalçın Özdilek, Funda Turan                   

Cumhuriyet University, Koyulhisar Vocational Training School, 58140, Koyulhisar, Sivas, TURKEY
Molecular Ecology and Fisheries Genetics Laboratory, Faculty of Marine Sciences and Technology, İskenderun Technical University, 31200, Iskenderun, Hatay, TURKEY
Department of Biology, Faculty of Science and Arts, Canakkale Onsekiz Mart University, Terzioglu Campus 17100 Çanakkale, TURKEY


Morphological differences between female and male hatchlings of green sea turtle (Chelonia mydas) were investigated to identify key morphological characters for sex determination. A total of 152 dead hatchlings of green sea turtles were examined for 14 morphometric and seven meristic characters in the 2008 and 2009 nesting seasons on Samandag Beach in the north-eastern Mediterranean Sea, Turkey. The sex of dead hatchlings was determined with gonad histology. Multivariate statistics revealed significant differences in three morphometric characters between females and males. The males had a longer curved carapace width (CCW), hind limb length (HLL) and plastron–cloaca length (PCL) than the females. Principal component analysis also supported the detected differences between sexes.

Keywords: Green Turtle, sex determination, gonad histology, morphology


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