One hundred and fifty specimens of Hexanchus griseus were caught by commercial fishing vessels in the seas of Turkey. Regarding the number of captured specimens per marine areas, the highest number ...of captures was recorded in the Sea of Marmara (90 specimens; 60%), followed by the Aegean (41 specimens; 27.3%), Mediterranean (15 specimens; 10%) and Black (3 specimens; 2%) seas. A single stranded individual was also recorded in the Canakkale Strait. Regarding the number of recorded specimens it is obvious that the Sixgill Shark Data Bank of Turkey holds a significant number of H. griseus specimens caught in the eastern Mediterranean Sea, both reported in historical and contemporary studies. The sex ratio of the examined specimens of H. griseus is 1:2.61 in favour of females. Analysis of the fishing gear used for 72 of 150 examined sixgill sharks indicates that the most common fishing gear used to catch H. griseus is purse-seine, followed by several types of bottom fishing gear.
A male shortfin mako shark (Isurus oxyrinchus) was caught on April 8, 2016, in the coastal waters of the Bay of Edremit by a commercial fisherman using nets set at the depths between 20 and 25 m. The ...specimen measured 74.7 cm in total length and weighed 2.75 kg. Its claspers were uncalcified, soft and shorter than the pelvic fins, revealing that it was a juvenile specimen. Upper and lower beaks of a cuttlefish (Sepia officinalis) were found in the stomach content. The nursery ground characteristics of I. oxyrinchus in relation to the feeding habit is also discussed.
Bluntnose sixgill shark, Hexanchus griseus (Bonnaterre, 1788), occurrs in Turkish waters from the eastern Black Sea to the eastern Mediterranean. Impacts of environmental deteriorations on bluntnose ...sixgill shark's distribution in the Black Sea (GSA 29), where the deep zone of the sea is permanently anoxic due to hydrogene sulphide contamination, and in the Sea of Marmara (GSA 28), where the hypoxia has been a raising concern for the last 40 years, is another issue in question. A decreasing trend in mean lengths of bluntnose sixgill sharks over the entire period (1967-2022) was found, which supposed "growth overfishing" of H. griseus in Turkish waters. Available information suggests possible breeding grounds of H. griseus in the Sea of Marmara, in the northern Aegean Sea (GSA 22) and in the northeastern Mediterranean Sea (GSA 24). The overlap of major fishing grounds of Turkish commercial bottom-trawling fleet with those suggested breeding grounds in the northern Aegean Sea and in the northeastern Mediterranean Sea, may cause further threat on the survival of the new generations of H. griseus in Turkish waters. Therefore, it is clearly seen that a management and conservation plan of H. griseus in Turkish waters should not solely rely on banning to capture and retain of bluntnose sixgill sharks on board, but should also provide a methodology to the fishermen of how to keep them alive to decrease or even prevent the at-vessel or post-release mortality. Such a plan should also implement an integrated ecosystem management approach for the conservation of those proposed breeding grounds.
Between January 2016 and April 2018, 3 juvenile great white sharks, Carcharodon carcharías (Linnaeus, 1758), were incidentally captured in the coastal waters of the Turkish Aegean Sea. Journeys of ...young-of-the-year (YOY) and juvenile specimens can increase the risk of their encountering fishing gears if the specimens head for regions where the fishery of the great whites is not banned. An understanding of the geographic range and knowledge of the vertical distribution of the YOY and juvenile great whites are therefore necessary to implement a management plan for great white populations in Turkish waters and to reduce the incidental fishing mortality of this vulnerable top predator.
In August 1998, a picture of a spinner shark, Carcharhinus brevipinna (Müller & Henle, 1839) was taken by an amateur group of divers at a depth of 3 m in Boncuk Bay (Gökova Bay, south Aegean Sea). ...Photographic evidence of this shark in Boncuk Bay contributes to our knowledge about the historical distribution of the species in Turkish waters. C. brevipinna is considered a very rare shark species in Turkish seas and needs immediate protection in Turkish territorial waters. The sighting of the spinner shark in the vicinity of a well-documented nursery ground of the sandbar shark, C. plumbeus, does not necessarily indicate a breeding ground for C. brevipinna in the studied area, as well; however, the possibility of a hypothetical nursery for the spinner shark in the Boncuk Bay area should be investigated in the future.
In August 1998, a picture of a spinner shark, Carcharhinus brevipinna (Muller & Henle, 1839) was taken by an amateur group of divers at a depth of 3 m in Boncuk Bay (Gokova Bay, south Aegean Sea). ...Photographic evidence of this shark in Boncuk Bay contributes to our knowledge about the historical distribution of the species in Turkish waters. C. brevipinna is considered a very rare shark species in Turkish seas and needs immediate protection in Turkish territorial waters. The sighting of the spinner shark in the vicinity of a well-documented nursery ground of the sandbar shark, C. plumbeus, does not necessarily indicate a breeding ground for C. brevipinna in the studied area, as well, however, the possibility of a hypothetical nursery for the spinner shark in the Boncuk Bay area should be investigated in the future.Original Abstract: Nell'agosto del 1998 uno squalo tissitore, Carcharhinus brevipinna (Muller & Henle, 1839), e stato ripreso da un gruppo amatoriale di subacquei ad una profondita di 3 metri nella baia di Boncuk (golfo di Gokova, mar Egeo meridionale). Le prove fotografiche della presenza di questo squalo nella baia di Boncuk contribuiscono alla conoscenza sulla distribuzione storica delle specie in acque turche. C. brevipinna e considerato quale specie molto rara di squali nei mari della Turchia e ha pertanto bisogno di una protezione immediata nelle acque territoriali turche. L'avvistamento dello squalo tissitore in prossimita di una ben documentata zona di crescita dello squalo grigio, C. plumbeus, non indica necessariamente una zona di riproduzione per C. brevipinna nell'area studiata. Tuttavia, la possibilita di un'ipotetica zona di crescita per lo squalo tissitore nella baia di Boncuk dovrebbe venir verifi cata in un prossimo futuro.
Il 9 aprile 2019, una femmina di squalo volpe occhione, Alopias superciliosus Lowe, 1841, e stata accidentalmente catturata da una rete a circuizione commerciale, a una profondita di circa 20 m, al ...largo della costa di Çevlik, nella baia di İskenderun, in Turchia. L'esemplare e il piu grande ad essere stato catturato nel Mar Levantino nord-orientale fino ad oggi. Si tratta inoltre di uno degli esemplari piu grandi, avvicinandosi al presunto limite massimo di 500 cm, catturato in tutto il mare Mediterraneo. Mentre lo squalo volpe, A. vulpinus, e ora considerato specie protetta dalla legge turca sulla pesca marittima, e urgentemente necessario uno stato di conservazione simile per la protezione di A. superciliosus.
Il 19 maggio 2022, un esemplare di Centrophorus uyato (Rafinesque, 1810) e stato accidentalmente agganciato da un peschereccio con palangari commerciali a 140 m di profondita nel Golfo di Antalya ...(Mediterraneo nord-orientale). Si trattava di una femmina immatura con una lunghezza totale di 663 mm e un peso totale di 1.505 g. Il tratto riproduttivo era sottile e filiforme. Nel contenuto dello stomaco sono stati trovati resti di pesci teleostei (Scomber sp., n=1; Boops boops, n=1). Le misure morfometriche di questo esemplare coincidono con quelle del clade A di C. uyato precedentemente delineato.
In August 1998, a picture of a spinner shark, Carcharhinus brevipinna (Mueller & Henle, 1839) was taken by an amateur group of divers at a depth of 3 m in Boncuk Bay (Gokova Bay, south Aegean Sea). ...Photographic evidence of this shark in Boncuk Bay contributes to our knowledge about the historical distribution of the species in Turkish waters. C. brevipinna is considered a very rare shark species in Turkish seas and needs immediate protection in Turkish territorial waters. The sighting of the spinner shark in the vicinity of a well-documented nursery ground of the sandbar shark, C. plumbeus, does not necessarily indicate a breeding ground for C. brevipinna in the studied area, as well; however, the possibility of a hypothetical nursery for the spinner shark in the Boncuk Bay area should be investigated in the future.
Status of the bramble shark, Echinorhinus brucus (Bonnaterre,1788), in the seas of Turkey has always been a point of debate until early 2000's. With the addition of 7 recent records from the seas of ...Turkey, which constitutes the 22.5% of the historical and contemporary records of the bramble shark from entire Mediterranean Sea, 31 individuals of E. brucus have been recorded from the entire region, and the record no. 7 of this present study is probably the most recently captured bramble shark, to date. Since 5 of the 7 recent records of E. brucus have been reported from the Sea of Marmara, special attention of research should be focused to this small inland sea to figure out whether this species has a localized population in this region or not.
