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The authors report on the capture of a specimen of smoothback angelshark Squatina oculata Bonaparte, 1840 from Turkish marine waters. The specimen measured 720 mm in total length and was caught by means of a commercial purse-seiner at a depth of 60 m. The species appeared to be sporadically caught in the area and the eastern Mediterranean Sea, however, the size diversity of recorded specimens shows the species still occurred in the region. Although the smoothback angel shark is listed as a protected species according to Turkish Marine Fisheries Act, a management plan should be integrated with local fisheries to preserve the species from extirpation throughout its distribution range in Turkish seas. [ABSTRACT FROM AUTHOR]

Two specimens of the thornback ray, Raja clavata Linnaeus, 1758, from Turkish waters, exhibiting deformities of disc and tail are described in the present paper. One of these specimens had a colour pattern similar to type 7, vermiculated, it could constitute a transitional step between Raja clavata and its close relative species Raja maderensis Lowe, 1838. [ABSTRACT FROM AUTHOR]

Background. The swordfish, Xiphias gladius Linnaeus, 1758, is a pelagic and highly migratory species distributed in the Atlantic, Indian, and Pacific oceans as well as in the Mediterranean Sea. Swordfish fishing has been carried out in the Mediterranean with longlines, gillnets, harpoons, and traps since the Roman times. Although information is available on the influence of the lunar phase on the catch per unit effort (CPUE) for the swordfish longline fishery in the Atlantic and Pacific oceans, the data concerning the Mediterranean is rather limited. The aim of this study was to examine the relation between the lunar phase and the swordfish CPUE, based on data from Turkish longline fisheries, targeting swordfish in the eastern Mediterranean during the 2008-2016 fishing seasons. Material and methods. We monitored randomly the daily fishing activity of longliners based at the ports of Fethiye and Özdere during 2008-2016. A total of 86 surveying operations were carried out, including 79 in the area between Fethiye and Alanya, the remaining ones were in Özdere in the southern Aegean coasts along the eastern Mediterranean Sea. The effect of the lunar phase on the swordfish catch rates, expressed in terms of kg · 1000 hooks-1, was examined by means of the Generalized Additive Modelling (GAMs) techniques. Results. The observed CPUE rates ranged from 0 to 700 kg · 1000 hooks-1. The mean swordfish CPUEs in the dark and light periods of the lunar cycle were equal to 178.10 ± 19.01 and 175.27 ± 19.56 kg · 1000 hooks-1, respectively. Although no significant differences among phases of the Moon were found (P > 0.05), CPUEs differed significantly between years (P < 0.05). Conclusion. It seems that the mechanism linking swordfish CPUE variations with the lunar cycle involves several factors, making difficult the identification of direct relations. Further studies are needed to better clarify the impact of the lunar phase on the longline gear, considering also additional parameters, such as light transition, prey abundance, physico-chemical characteristics of the marine environment, and the soak time of the gear. [ABSTRACT FROM AUTHOR]

Blackchin guitarfish, Rhinobatos cemiculus, is rather abundantly captured in the eastern tropical Atlantic, especially off Senegal and Mauritania. In the Mediterranean western basin, R. cemiculus is unknown at present off the European shore but is rather frequent off southern areas; conversely, the species occurs throughout the eastern basin. Two large specimens recorded for the first time in İzmir Bay, northern Aegean Sea, are reported and described in this note. These findings constitute the northernmost records of R. cemiculus in both the Aegean Sea and the Mediterranean Sea, and they significantly extend the species' distribution known to date. [ABSTRACT FROM AUTHOR]

A specimen of Champsodon vorax Günther, 1867, of 113 mm SL, was caught on 6 September 2014 with a bottom trawl from the entrance of the Bay of Izmir, north-eastern Aegean Sea at a depth of 65 m. The presently reported study constitutes the fi rst record for the Aegean Sea but also the fourth record for the Mediterranean Sea. The specimen described in this paper is the largest individual reported to date from the Mediterranean. As it is evident from the spatial dynamics of all successive records of C. vorax in the Mediterranean this gaper seems to be a rapidly expanding species. It disperses both westwards and northwards. [ABSTRACT FROM AUTHOR]

On 2 August 2013, a specimen of the cobia, Rachycentron canadum (Linnaeus, 1766), was caught off Marmaris, south-eastern Aegean coast of Turkey. The fish was examined and morphometric characteristics of the specimen collected were determined. The species is being reported from the second time in the Mediterranean, preceded by its first occurrence off Haifa, Israel in 1978. The newly caught specimen was larger (SL) than the previously recorded individual (923 mm vs. 766 mm). All measurements, counts, and colour patterns determined were consistent with earlier published descriptions of the species. [ABSTRACT FROM AUTHOR]