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    Management Recommendations for Common Carp Fisheries in Turkey in Light of Their Reproductivity and Gear Selectivity
    (Faculty of Fisheries, Kasetsart University, 2022) Dereli, Hakkı; Şen, Yusuf; Kebapçıoğlu, Turhan; Erdoğuş, Mirati; Ölçek, Zeki Serkan; Özdemir, Murathan; Ulman, Aylin
    Common carp Cyprinus carpio (Linnaeus, 1758) is a very important freshwater commercial species in Turkey, but landings there decreased by 73 % from 2008 to 2019. There are knowledge gaps regarding the reproductive biology of the species and the selectivity of fishing gear types in Turkish lakes. This study aims to determine appropriate management measures for common carp fisheries based on gillnet and trammel net selectivity and reproductive characteristics of the species. A study was undertaken with local commercial fishers between June 2015 and December 2016 in Demirköprü Dam Lake in Western Turkey. The spawning season peaked in March, with a secondary spawning season suggested in October/November. Their length at 50 % maturity (Lm50) was 38.7 cm for females and 32 cm for males. Modal lengths for gillnets and trammel nets determined by SELECT method were larger than the minimum landing size (40 cm) and the Lm50 values. However, sub-minimum landing size individuals were captured at high rates by both types of nets with 65 mm mesh. Trammel nets had lower modal lengths and larger spread values than gillnets of the same mesh size. These results demonstrate that some management measures currently applied in carp fishery management are insufficient for stock sustainability. © 2022, Faculty of Fisheries, Kasetsart University. All rights reserved.
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    The effect of gillnet twine thickness on catching efficiency and selectivity for common carp (Cyprinus carpio Linnaeus, 1758) fishery in Marmara Lake
    (Ege Univ, Fac Fisheries, 2022) Dereli, Hakki; Kebapcioglu, Turhan; Sen, Yusuf; Olcek, Zeki Serkan; Dincturk, Ezgi; Ulman, Aylin
    The effects of multifilament gillnet twine thickness on selectivity and catching efficiency for the common carp fishery were investigated in this study. Sampling was carried out with multifilament gillnets of two different twine thicknesses (with 210d/2 and 210d/3) on 140, 150, 160, 180, 200 mm mesh sizes between June 2015 and December 2016 in Marmara Lake, located in Western Turkey. Higher modal lengths and lower catch per unit effort (CPUE) values and lower sub-minimum landing size (MLS) individuals rate (excluding 180 and 200 mm mesh sizes) were obtained in the thick multifilament material (210d/3) with the same mesh size compared to thin material (210d/2). All mesh sizes in both twine thickness provided modal lengths above the MLS. However, the thin twine material had a higher nominal percentage of undersized fish (8%), greater than the 5% accepted limit for total catches when all mesh sizes are considered together. As a result, the modal lengths and spread values increased and the selectivity and catching efficiency decreased with the thicker twine material.
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    The lionfish expansion in the Aegean Sea in Turkey: A looming potential ecological disaster
    (Elsevier, 2020) Ulman, Aylin; Tuncer, Sezginer; Kizilkaya, Inci Tuney; Zilifli, Aytug; Alford, Polly; Giovos, Ioannis
    The lionfish invasion in the Western Atlantic is understood to be one of the worst marine invasions in history, and they have recently just invaded the Mediterranean. Lionfish are a marine `pest' species in invaded areas, mostly due to their venomous spines combined with their insatiable appetites. The devil firefish's (Pterois miles) Mediterranean invasion began in 2012 in Lebanon and has since been rapidly spreading westwards. They are now found along Turkey's entire southern coastline, first reported in Iskenderun Bay in 2015, and are now expanding into the Aegean Sea. New records here are presented for Turkey; in May 2019, two lionfish specimens (Pterois miles, [Bennet, 1828]) were caught in Bodrum, Turkey (Aegean Sea), and just one month later, they were found in Seferhisar (Izmir province), about 100 nautical miles north of Bodrum, now the most northern record for Turkey. They were already reported in the Greek Dodecanese Islands (situated between these two sites), showing their establishment in the area and the necessity for scientists from different countries to work together on accurate assessments. While a second lionfish species, Pterois volitans has recently been reported in Turkey, newer research has shown that P. volitans found in the invaded Caribbean region, is a hybrid species between P. miles and a Pacific lineage encompassing Pterois lunulata/russelii. Thus, in light of this new research, P. volitans should not be confirmed in the Mediterranean from morphological characters alone, which are highly variable, and genetic testing is required to decipher its identity. Along with these new records highlighting the recent expansion of the invaded range, lessons learned from the Caribbean invasion are provided to help prepare Mediterranean scientists and officials to better tackle this invasion. Two control methods are discussed to help reduce populations by getting them from the sea to plates: fishing and culling along with an introduction to local cuisines. (c) 2020 Elsevier B.V. All rights reserved.