Yumuşak Kabuklu Nil Kaplumbağası (Trionyx triunguis): Yuva parametreleri ve yeni bir yuvalama alanı

Türkiye’de bulunan Trionyx triunguis (Yumuşak Kabuklu Nil Kaplumbağası) yuva parametreleri ile ilgili batı Akdeniz sahillerinde yapılan az sayıda çalışma dışında bir çalışma bulunmamaktadır. Bu çalışmada, Türkiye’nin orta ve doğu Akdeniz sahillerinde bulunan Belek, Göksu ve Burnaz kumsallarında 12 adet Yumuşak Kabuklu Nil Kaplumbağası yuvasına ait 2016 ve 2017 sezonlarındaki yuva parametreleri değerlendirilmiştir. Yuvalamaların mayıs ayında (%17) başladığı ancak haziran ayında (%83) yoğunlaştığı görülmüştür. Yuvaların kıyı çizgisine uzaklığı, derinliği, sıcaklığı, kuluçka büyüklüğü ve yavru çıkışı başarıları hesaplanmıştır. Çalışmanın gerçekleştirildiği üç kumsalda en düşük yavru çıkışı başarısı Göksu Kumsalı’nda (0,18 ± 0,26) iken Belek (0,75 ± 0,22) ve Burnaz (0,72 ± 0,36) birbirine yakın değerdedir. Kuluçka sıcaklıkları, embriyoların sağlıklı bir şekilde gelişebileceği aralıkta (29,5–33,0 °C) ölçülmesine karşın, yuva içerisindeki yumurtaların en fazla geç embriyonik dönemde öldüğü (5,1 ± 9,6) bunu erken (1,8 ± 3,1) ve orta dönem (0,3 ± 0,6) embriyoların izlediği tespit edilmiştir. Döllenmemiş yumurta sayıları en yüksek Burnaz Kumsalı’nda (14,5 ± 19,1) ve en düşük Belek Kumsalında (1,0 ± 1,5) kaydedilmiştir. Yuva parametrelerinin birbirleri arasındaki ilişkileri incelendiğinde yalnızca yuva içi sıcaklığının, kuluçka büyüklüğü ile istatistiksel olarak anlamlı bir ilişki gösterdiği tespit edilmiştir. Bu çalışma ile, Burnaz kumsalı Yumuşak Kabuklu Nil Kaplumbağası için yeni bir yuvalama alanı olarak tespit edilerek, bu türün üç kumsala ait yuvalarındaki yuva parametreleri ortaya konmuştur

Anahtar Kelimeler:

Trionyx triunguis, yuva parametreleri, sıcaklık, Burnaz Kumsalı, Akdeniz

The Nile Softshell Turtle (Trionyx triunguis): Nest Parameters and A New Nesting Site

There are no studies carried out on nest parameters of the Nile softshell turtle (Trionyx triunguis) in Turkey except for few studies on the Western Mediterranean coast of Turkey. In this study, 12 nests of the Nile softshell turtle were examined in terms of nest parameters during 2016 and 2017 nesting seasons on Belek, Göksu, and Burnaz beaches located on the Central and Eastern Mediterranean coast of Turkey. Nesting period started in May (17%) but intensified in June (83%). The distance of nests to the shore, depth of nests, clutch temperature, clutch size, and hatching success in the nests were recorded and calculated. Among three beaches, the lowest hatching success rate was on Göksu Beach (0.18 ± 0.26), whereas the values were similar on Belek (0.75 ± 0.22) and Burnaz (0.72 ± 0.36) beaches. Although clutch temperatures were measured in a range (29.5–33.0 °C) that is optimal for embryo development, most of the eggs inside nests were dead at the late embryonic period (5.1 ± 9.6) which was followed by early (1.8 ± 3.1) and middle stage embryos (0.3 ± 0,6). The highest number of unfertilized eggs was recorded on Burnaz Beach (14.5 ± 19.1) and the lowest was on Belek Beach (1.0 ± 1.5). Regarding the relationship between the nest parameters, it was detected that only the clutch temperature has a significant relationship with the clutch size. In this study, a new nesting site for the softshell Nile turtle on Burnaz Beach was discovered and nest parameters in this species were indicated on three beaches.

Keywords:

Trionyx triunguis, nest parameters, temperature, Burnaz Beach, Mediterranean Sea,

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