Common Dolphin, Delphinus delphis (Cetacean: Dolphinidae) Stranding off Sinop Peninsula in the Black Sea

Abstract

The present study summarizes information on the stranding common dolphin, Delphinus delphis, off the Sinop peninsula and also describes information on the weight-length relationships of the common dolphin in the center Black Sea, Turkey for the first time. During the research period, a total of 10 D. delphis were examined as stranding off Sinop Peninsula. It was determined that a lot of water birds species (Great cormorant) were seen as died on the sea coast during the dolphin survey. The death reasons of the common dolphin were drowned after the catching the nets and it is also suspected that death reason of common dolphins is water pollution. The length weight relationship (WLRs) of D. delphis determined as Log (W) = 2.2898 L - 2.6501, r² = 0.9959 (n = 7). It is important that standing levels of Cetaceans living in the Black Sea in terms of protection efforts. It is also important to investigate the causes of death. Focusing on these topics in subsequent studies will be important for the protection of endangered (Phocoena phocoena and Tursiops truncatus) and vulnerable (D. delphis) cetaceans in the Black Sea.

Keywords

• Cetaceans,Common dolphin,Delphinus delphis,Stranding,Black Sea

Karadeniz Sinop Yarımadasında Karaya Vuran Tırtak Türü (Delphinus delphis) Yunuslar

Öz

Bu çalışmada, Sinop yarımadası civarında karaya vuran tırtak türü (Delphinus delphis) ve bu türün boy-ağırlık ilişkisini orta Karadeniz’de ilk kez özetlemektedir. Çalışma süresince 10 adet yunus bireyi karaya vurmuş olarak tespit edilmiş ve incelenmiştir. Çalışma süresinde ölü yunusların yanında çok sayıda ölü su kuşu (Great cormorant) da tespit edilmiştir. Karaya vuran yunusların ölüm nedeninin balıkçı ağlarına dolanıp boğularak öldükleri düşünülmektedir. Ayrıca su kirliliğinin de ölümler üzerine etkili olabileceğinden şüphelenilmiştir. İncelenen yunusların boy ağırlık ilişkisi Log (W) = 2,2898 L – 2,6501, r² = 0,9959 (n = 7) şeklinde hesaplanmıştır. Karadeniz’de Cetacea türlerinin korunması önlemleri açısından karaya vuran miktarının ve ölüm sebeplerinin bilinmesi önemlidir. Bu kapsamda tehlike altında (Phocoena phocoena ve Tursiops truncatus) ve hassas (D. delphis) kategorisindeki yunus türleri üzerine daha fazla çalışma odaklanmalıdır.

Anahtar Kelimeler

• Delphinus delphis,Cetacea,Tırtak,Karaya vurmak,Karadeniz

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