Samandağ Kumsalı Yeşil Deniz Kaplumbağası (Chelonia mydas) Yuvalarında Memeli Predasyonunun Zamansal ve Mekansal Değişiminin İncelenmesi

Abstract

Yuva predasyonu, birçok nesli tükenmekte olan kuş ve sürüngen türünün korunması için önemli bir pratik zorluktur ve yavru başarısını azaltma ve tehdit altındaki popülasyonların iyileşmesini yavaşlatma potansiyeline sahiptir. Yuva predasyonunun zamansal ve mekansal değişiminin tahmin edilmesi predasyon yönetimini optimize etme potansiyeline sahiptir. Bu çalışmada, Samandağ kumsalında yeşil deniz kaplumbağası (Chelonia mydas) yuvalarında memeli predasyonunun zamansal ve mekansal değişimleri araştırıldı. 2012 ve 2017 yılları arasında 733'ü metal ızgaralı kafes ile korunan, 231'i ise metal ızgara ile korumaya alınmamış kontrol yuvaları olan toplam 964 yuva araştırıldı. En etkili yuva predatörü Çakal olarak tespit edildi. Yuvaların metal ızgaralı kafes ile korunması yavru başarısını etkin bir şekilde arttırdı. Predasyona uğrayan yuva sayısı yıllara göre pozitif bir eğilim gösterdi, ancak bu eğilim istatistiksel olarak anlamlı değildi. Predasyon olasılığı kuluçka döneminin sonuna doğru arttı ve deniz ve bitki örtüsüne olan mesafeye göre mekansal değişimde farklılık ortaya çıkmadı. Ayrıca, kumsalın sonuna doğru predasyon olasılığı arttı. Yuva yoğunluğu ve yuva derinliklerine bağlı predasyon olma ihtimalinin ileride araştırılması önemlidir. Ayrıca Samandağ sahilinde baskın yırtıcı olan Çakalların populasyon ekolojisi ve statüsünün araştırılması da her iki tür için de önemlidir.

Keywords

• Chelonia mydas,Samandağ,Predasyon,Canis aureus,Yeşil deniz kaplumbağası,Samandağ

Investigation of Temporal and Spatial Variation of Mammalian Predation in Green Sea Turtle (Chelonia mydas) Nests on Samandağ Beach, Eastern Mediterranean Turkey

Öz

Nest predation is an important practical challenge for the protection of many endangered species of birds and reptiles, and has the potential to reduce hatching success and slow the recovery of the threatened populations. Estimating the temporal and spatial variation of the nest predation has the potential to optimize predation management. In this study, the temporal and spatial variation of mammalian predation was investigated in the green sea turtle (Chelonia mydas) nests on Samandağ beach, Eastern Mediterranean, Turkey. A total of 964 nests were examined between 2012 and 2017, which 733 of them were protected with screened metal grid and 231 of them unscreened control nests. The most effective nest predator was identified as the Jackal (Canis aureus). The protection of the nests with the screened metal grid has effectively increased the hatching success. The number of predated nests showed a positive trend over the years, but this trend was not statistically significant. The likelihood of predation increased towards the end of the incubation period, and did not change in the spatial variation according to the distance to the sea and vegetation. Also, the likelihood of the predation increased towards the end of the beach. Investigation of the likelihood of predation by nest density and nest depth in future studies is important. Also, the investigation of population ecology and status of the Jackals, which is predominant predators on the Samandag beach, is important for the both species.

Anahtar Kelimeler

• Chelonia mydas,Samandağ,Predation,Canis aureus,Green sea turtle,Samandağ

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