Temperature Profiles And Sex Ratio Estimation For Green Turtle Chelonia mydas Hatchlings On Sugözü Beaches

Year 2014, Volume: 42 Issue: 4, 531 - 536, 01.11.2014

Onur Candan Dürdane Kolankaya

Abstract

In this study, the effect of nest temperature and surrounding sand temperature on sexual differentiation were examined for green turtle Chelonia mydas hatchlings on Sugözü Beaches Adana, Turkey in 2005 nesting season. Nest temperatures were found to be higher than the surrounding sand temperatures, especially du- ring the middle and last third period of incubation respectively, 0.6°C and 1.9°C . The nest temperature was mostly related to the incubation duration and this was followed by the distance of the nest from the sea and the clutch size. Any relationship between nest temperature and nest depth was not found. Nest temperatures ranged between 29.4-31.6°C and middle third temperatures ranged between 29.5-31.3°C were measured above 28.9°C, which is the pivotal temperature. The sex ratio in green turtle hatchlings in the area investigated according to the temperature profile was prominently biased toward females.

Keywords

Eastern Mediterranean, incubation, sea turtle, Sugözü Beaches, temperature dependent sex determination

Sugözü Kumsalları’ndaki̇ Sıcaklık Profilleri ve Yeşil Kaplumbağa Chelonia mydas Yavrularında Eşey Oranı Tahmini

Abstract

B u çalışmada, 2005 yuvalama sezonunda Sugözü Kumsalları’ndaki Adana, Türkiye yuva ve çevresindeki kumsal sıcaklıklarının yeşil kaplumbağa Chelonia mydas yavrularındaki eşeysel farklılşmaya olan etkisi incelenmiştir. Yuva sıcaklıkları, özellikle gelişimin orta ve son trimesterinde sırasıyla 0.6°C ve 1.9°C yuvayı çevreleyen kumsal sıcaklıklarından yüksek bulunmuştur. Yuva sıcaklıkları en yüksek olarak inkübasyon süresi ile ilişkilidir, bunu yuvanın denizden uzaklığı ve kuluçka büyüklüğü izlemektedir. Yuva sıcaklığı ve yuva derinliği arasında bir ilişki bulunamamıştır. Yuva 29.4-31.6°C arasında ve orta trimester 29.5-31.3°C arasında sıcaklıkları 28.9°C olan pivotal sıcaklık derecesinin üzerinde ölçülmüştür. Sıcaklık profillerine gore, çalışma alanındaki yeşil kaplumbağa yavrularındaki cinsiyet oranı belirgin şekilde dişi yönlüdür

Keywords

Doğu Akdeniz, inkübasyon, deniz kaplumbağası, Sugözü Kumsalları, sıcaklığa bağlı eşey belirlenmesi

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