Embryonic mortalitiy in loggerhead turtle (Caretta caretta) nests: A Comparative study on Fethiye and Göksu Delta Beaches

Bu araştırmada, 2004 ve 2005 üreme sezonunda Fethiye ve Göksu sahillerine yuva yapan 66 Caretta caretta Deniz Kaplumbağası yuvasındaki embriyo ölümleri karşılaştırılarak incelenmiştir. 5012 adet yumurta sayılmış ve bunların 2751’inden (% 54,90) başarıyla yavru çıkışı olmuştur. Yavru çıkışı olmayan 2261 adet yumurtanın 68’i (% 1,35) tanımlanamayan yumurta, 2193 (% 43,75) ise ölü embriyo olarak sınıflandırılmıştır. Bu ölü embriyolar içinde yüksek yüzdeli olanlar, erken (% 23,48- 1177 yumurta) ve ileri gelişim safhalardır (% 16,24- 814). En düşük ise orta safha yüzdesidir (% 4,03- 202). Göksu sahilinin ölü embriyo oranı, Fethiye sahilinden daha yüksektir. Bu çalışmaya dahil edilen hiçbir ekolojik değişken erken safha embriyo ölümünü açıklamamaktadır. Yuvaların eğimi düştükçe ve kuru kum derinliği azaldıkça orta ve ileri safha embriyo ölümleri artmaktadır. Bununla birlikte, yuva nemi ve ıslak kum derinliği azaldıkça ise bu iki safha embriyo ölümleri azalmaktadır.

İri başlı Deniz kaplumbağası (Caretta caretta) yuvalarında embriyonik mortalite: Fethiye ve Göksu Deltası sahilleri üzerine karşılaştırılmalı bir araştırma

In total, 66 loggerhead turtle nests were examined and compared in terms of embryonic mortality during the 2004 and 2005 breeding seasons on Fethiye and Göksu Delta beaches. In all, 5012 eggs were counted, 2751 (54.90%) of which hatched successfully. Of the 2261 unhatched eggs, 68 (1.35%) were classified as unidentified eggs and 2193 (43.75%) were classified as containing dead embryos. Of these dead embryos, a high percentage were in the early stage (n = 1177, 23.48%) and late stage (n = 814, 16.24%,) of development. The lowest percentage of the eggs with dead embryos (n = 202, 4.03%) were in the midstage of development. The embryonic mortality rate was higher at Göksu Delta than at Fethiye Beach. Of the examined ecological variables, none accounted for the early stage embryonic mortality. Embryonic mortality in the middle and late stages of development increased with decreasing slope and dry sand depth of the nests; however, embryonic mortality during these stages decreased with declining moisture and wet sand depth of the nests.

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Turkish Journal of Zoology-Cover
  • ISSN: 1300-0179
  • Yayın Aralığı: Yılda 6 Sayı
  • Yayıncı: TÜBİTAK
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