Yazar "Ozdemir, Suleyman" seçeneğine göre listele

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    An important species for Black Sea biodiversity: Some population characteristics of invasive sea vase ( Ciona intestinalis Linnaeus, 1767) distributed on the Sinop shores
    (Tubitak Scientific & Technological Research Council Turkey, 2024) Birinci Ozdemir, Zekiye; Aydemir Cil, Eylem; Ozdemir, Suleyman; Duyar, Hunkar Avni
    This study aimed to provide a comprehensive summary of the fundamental biological and certain population characteristics of Ciona intestinalis found along the Black Sea coasts of T & uuml;rkiye. The research was conducted between September 2022 and 15th, 2023, off the Sinop coast of the Black Sea, utilizing samples collected by commercial fishing vessels in the region. A total specimens of C. intestinalis were examined during the study. The average total length, width, and weight of C. intestinalis were +/- 0.089 cm, 1.967 +/- 0.054 cm, and 2.004 +/- 0.067 g, respectively. The length-weight relationship (LWR) and length-width relationship (LWdR) of C. intestinalis were established as W = 0.3996L1.2424 (R = 0.9389), Wd = 0.5362L + 0.0237 (R = 0.8897), and W = 0.9443Wd1.0889 (R = 0.8786), respectively. This study presents, for the first time, the LWR, LWdR, and WdWR for C. intestinalis, a species of significant importance in the benthic ecosystem of the Black Sea. It is anticipated that this research will lay the groundwork for future investigations into the population dynamics and biological aspects of this species.
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    Determination of catch eficiency and lenght composition of anchovy (Engraulis encrasicolus L., 1758) caught by midwater trawl during nihgt in the Black Sea
    (Ege Univ, 2006) Ozdemir, Suleyman; Erdem, Yakup; Satilmis, Hasan Huseyin; Ozdemir, Zekiye Birinci
    The aim of this study is to determine catch amount and size composition of anchovy in pelagic trawl along night time that carried out at fishing season 2005-2006 in Black sea. Night time was divided 3 periods as 17:00-20:00, 21:00-00:00 and 01:00-04:00, and was performed 6 tows for each period. Total 138 180 kg fish was fishing along study, I. period II. period and III. period 34 560 kg, 66 360 and 37 260 kg respectively. Mean size of all fishes caught 10,19 +/- 0,03 cm were determined, I. II. and III. period 10,26 +/- 0.05 cm; 9,89 +/- 0,04 cm and 10,42 +/- 0,09 cm respectively. Difference between Catch efficiency and mean size for fishing operation was done at different time periods was significantly (p<0,05). Change of school structure and movements showed in anchovy fishing by midwater trawl and depend on that be variation especially in catch efficiency and size composition were determined. Besides although decreasing of catch efficiency is at sun set and dawn due to there is less saturation on the net, more size fishes as to midnight fishing in these periods could be saying.
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    Determination of Selectivity Monoflament and Multiflament Gillnets with Different Mesh Size for bluefish (Pomatomus saltatrix L., 1766)
    (Ege Univ, 2010) Sumer, Cetin; Ozdemir, Suleyman; Erdem, Yakup
    In this study has been applied to determine the selectivity of mono and multifilament gillnets with 40 and 44 mm mesh size for blue fish (Pomatomus saltatrix L., 1766). This study was carry out from October 2001 till February 2002 in the inner harbour of Sinop. Holt (1963) method, which is the indirect calculation method, was used to determine the selectivity of gillnets. Proportion of caught fish by monofilament and multifilament gillnets were 76.65% and 23.35%, respectively. Acording the results, the common selection factor was found as 4.58 for monofilament and 4.74 for multifilament gillnets.
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    Determination of Selectivity Monoflament and Multiflament Gillnets with Different Mesh Size for Horse Mackerel (Trachurus trachurus L., 1758)
    (Ege Univ, 2010) Sumer, Cetin; Ozdemir, Suleyman; Erdem, Yakup
    In this study it was investigated that the selectivity of monofilament and multifilament gillnets with mesh sizes from 36 to 40 mm for fishing horse mackerel (Trachurus trachurus, L., 1758) between October 2001 and February 2002 inside harbour of Sinop. Selectivity parameters were estimated using the indirect method proposed by Holt (1963) method. A total of 3520 specimens were collected by experimental nets. 53.86% and 46.14% of them were caught by monofilament and multifilament gillnets, respectively. The common selection factor was found as 4.90 for monofilament and 4.84 for multifilament gillnets.
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    Determination of Size Selectivity of Traps for Blue Crab (Callinectes sapidus Rathbun, 1896) in the Mediterranean Sea
    (Ankara Univ, Fac Agr, 2015) Ozdemir, Suleyman; Gokce, Gokhan; Cekic, Mustafa
    This study investigates the effects of trap selectivity of various mesh size on escape success of the blue crab (Callinectes sapidus). The study was carried out Camlik Lagoon of Yumurtalik Gulf in the Mediterranean Sea and total of 1051 blue crabs were caught by rectangular baited trap. Using traps constructed with 30, 35, 40, 45 and 50 mm square mesh the proportion of crabs escaping through each mesh size was measured for each half centimetre carapace width (CW) class. A logistic model was fitted to the size frequency data of the retained and escaped blue crabs for each mesh size in the experiment. L-50 and selection range (SR) for the 30, 35, 40, 45 and 50 mm (bar length) square meshes tested in this study was 8.47 cm and 0.85 cm; 9.31 cm and 0.39 cm; 10.40 cm and 0.31 cm; 11.72 cm and 1.17 cm; 13.17 cm and 0.89 cm respectively. The 50 mm square mesh of the trap showed relatively better selectivity considering the size at 50% sexual maturity of blue crab Callinectes sapidus, and the high rate of immature escapers.
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    Effect on catchability of species and species selectivity of structure properties and net material of gillnets
    (Ege Univ, 2006) Ozdemir, Suleyman; Erdem, Yakup
    In this study the catch composition, species selectivity and catchability of species catch of set nets having monofilament and multifilament material were compared. Nets used on experiments have 36 mm mesh. More fish (58,81 %) caught by monofilament net of important portion of fishes (95,84 %), including economical species of less portion of fishes (92,67 %) fished by multifilament nets (41,19 %) were determined. The portion monofilament and monofilament in completely economical species were calculated 40,38 %, 59,62 % respectively. Gillnets more effective than trammel nets viewpoint both fished fishes amount and target species catch ratio were established. Gillnets more be selective (p<0,05) than trammel nets were considered at the length composition of horse mackerel (Trachurus trachurus, L. 1758), red mulled (Mullus barbatus ponticus, E., 1927) and whiting (Merlangius merlangus euxinus, N. 1840) including target species were investigated. Mostly, increasing of bycatch amount more active than excess of total catch for profitable and continuing fishing were designated and as the results using of monofilament and gillnet in fishing of target species is more appropriate were concluded.
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    Effects of square mesh panels position of bottom trawls on by-catch bluefish Pomatomus saltatrix (Linnaeus, 1776) selectivity in the Southern Coast of the Black Sea, Turkey
    (Cahiers De Biologie Marine, 2014) Ozdemir, Suleyman; Erdem, Yakup; Erdem, Ercan; Ozdemir, Zekiye Birinci
    The selectivity parameters for by-catch bluefish Pomatomus saltatrix caught by demersal trawl, a nominal 40 mm diamond mesh size codend outfitted with square mesh escape panels, was determined on the southern coast of the Black Sea. Square mesh panels of nominal 36 mm were evaluated in two separate combinations: left-right and middle on the codend. The 50% retention lengths (L-50) and selection ranges of left-right (SDS), middle (DSD) combinations and control codend for blue fish were estimated to be 13.03 and 3.82 cm, 12.91 and 3.71 cm, 12.49 and 3.68 cm respectively. The L-50 value of SDS and DSD codend were comparable with the L-50 value of the control codend; however, the control codend value was rather low. The values of SDS and DSD codend weren't very close to MLS of the bluefish (20 cm). For this reason, more than 36 mm square mesh panels can be used alternatively, instead of the 36 mm square mesh panel on the codends for the fishery of the bluefish and higher size selectivity can be obtained. However, it may not be successful fisheries when considering the minimum landing size for dominant species (whiting Merlangius merlangus (Linnaeus, 1758) and red mullet Mullus barbatus ponticus (Essipov, 1927), 13 cm) in the Black Sea trawl fishery. These results show that increasing the size selectivity in a multi-species trawl fishery using a single position or square mesh size is quite difficult. Furthermore, square mesh panel codends were more selective than diamond mesh codend (p < 0.05). Differences between left-right (SDS) position and middle (DSD) position were no significant (p > 0.05) for the square mesh panel codend. Although the left-right (SDS) combination had a higher total area than the other combination (DSD) with square mesh in the middle and was preferable for bluefish.
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    Lenght-weight Relationships, Condition Factor Index and Meat Yield of Rapa Whelks (Rapana venosa Valenciennes, 1846) in the Yakakent Regions (Southern Blacksea)
    (Adem Yavuz Sonmez, 2016) Bayrakli, Baris; Ozdemir, Suleyman; Birinci Ozdemir, Zekiye
    Length-Weight Relationships, Condition Indexes and Meat Yields of Rapa Whelks (Rapana venosa Valenciennes, 1846) in Yakakent (the southern Black Sea) were investigated. This study was to determine the length-weight relationships, condition indexes and meat yields of Rapana venosa in Yakakent (Samsun, Black Sea). For this aim, 431 rapa whelk specimens were sampled at monthly intervals between December 2014 and November 2015. The total length and weight of the specimens ranged from 43.52 to 109.52mm and from 15.42 to 234.53g, respectively. The length-weight equation calculated as W=0.0007 L2.7287 (r2 = 0.91). Negative allometric growth (t = 6.4432, P<0.05) was observed for rapa whelks. The condition indexes varied between 2.58-40.43 with a mean 15.74 +/- 0.26. The highest mean condition index (24.52) was recorded in January and the lowest (11.17) in July. Meat yields ranged from 9.08% to 46.27% with a mean 29.32 +/- 0.29, the highest in January (36.45%) and the lowest in September (23.30%).
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    Length-weight relationships of the three most abundant pelagic fish species caught by mid-water trawls and purse seine in the Black Sea
    (Cahiers De Biologie Marine, 2014) Satilmis, Hasan Huseyin; Sumer, Cetim; Ozdemir, Suleyman; Bayrakli, Baris
    Length-weight relationships were estimated for the three most abundant and frequently caught pelagic fish species, anchovy Engraulis encrasicolus ponticus, horse mackerel Trachurus mediterraneus ponticus, and sprat Sprattus sprattus phalericus caught by mid-water trawls and purse seine between November 2002 and November 2003 in the Black Sea. The values of the slope b in the length-weight relationships ranged between 2.969 and 3.134, with a mean of 10.95 +/- 0.03 cm total length (TL) for anchovy, between 3.003 and 3.099, with a mean of 9.55 +/- 0.04 cm TL for sprat, between 3.250 and 3.290, with a mean of 13.60 +/- 0.07 cm TL for horse mackerel. Isometric growth (Pauly's t-test, P > 0.05) was observed in females and all individuals for sprat, in males and all individuals for anchovy. Positive allometric growth (Pauly's t-test, P < 0.05) was estimated in males for sprat, females for anchovy and females, males and all individuals for horse mackerel.
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    Microplastic-induced oxidative stress response in turbot and potential intake by humans
    (Taylor & Francis Ltd, 2024) Kokturk, Mine; Ozgeris, Fatma Betuel; Atamanalp, Muhammed; Ucar, Arzu; Ozdemir, Suleyman; Parlak, Veysel; Duyar, Hunkar Avni
    Microplastic (MP) pollution has become a health concern subject in recent years. Althoughann increasing number of studies about the ingestion of microplastics by fish, research on the oxidative stress response to MPs in natural environments is quite limited. In this study, the identification and characterization of MPs in gill (G), muscle tissues (M), and gastrointestinal tract (GI) of turbot (Scophthalmus maximus) were evaluated. Oxidative damage of MPs on the brain (B), liver (L), gill (G), and muscle (M) tissues as well as their effect on superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), paraoxonase (PON), arylesterase (AR) myeloperoxidase (MPO), and malondialdehyde (MDA) biomarkers were evaluated. The potential transmission of MPs from muscle tissues to humans was examined. Results showed that gills contain the highest amounts of MPs, ethylene propylene is the most dominant polymer type, black and blue are the most common MP color, fiber is the most common shape, and 50-200 mu m is the most common MP size. Results showed that MPs cause oxidative stress of tissues with inhibiting effect on enzyme activities and promoting impact on lipid peroxidation. The oxidative damage mostly affected the liver (detoxification organ) followed by gill tissue. The intake of MPS in the European Union was estimated by EFSA as 119 items/year, while in Turkey it is 47.88 items/year. This study shows that more research is needed in terms of ecosystem health and food chain safety. The risk assessment of MPs in living organisms and environmental matrices including food safety and human health should be considered a public health issue.
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    Microplastics in Tissues (Brain, Gill, Muscle and Gastrointestinal) of Mullus barbatus and Alosa immaculata
    (Springer, 2021) Atamanalp, Muhammed; Kokturk, Mine; Ucar, Arzu; Duyar, Hunkar Avni; Ozdemir, Suleyman; Parlak, Veysel; Esenbuga, Nurinisa
    The researches on MPs in commercial marine fish are very limited although in marine environments microplastic (MPs) pollution is a global problem. In this study, the presence, composition, and characterization of MPs in different tissues (brain, gill, muscle, and gastrointestinal tract) of commercial fish species [red mullet (Mullus barbatus) and pontic shad (Alosa immaculata Bennett 1835)] from the Black Sea were investigated. M. barbatus (demersal) and A. immaculata (pelagic) fish were preferred in the selection of fish species in order to represent demersal and pelagic environments. After dissected the fish, MPs were obtained from the tissues by extraction using the flotation method; then the MPs were counted and categorized according to shape, size, and color. The composition of the MPs was determined via ATR-FTIR spectroscopy. In terms of microplastic abundance in fish tissues, the gastrointestinal tract (40.0%) ranked first in both fish species, while the lowest MPs density was determined in brain tissues (7.0%). After the gastrointestinal tissue, gills were identified as the second tissue with the highest MPs density. Regardless of fish species, MPs characterization was mainly fibrous (51.0%), black colored (49.0%), and 50-200 mu m in size (55.0%). Among the nine different polymers determined, polychloroprene (18.8%) and polyamide (15.0%) were found most frequently. This research provides data for tissue-based assessment of MPs in fish. The obtained data showed that MPs (one of the anthropogenic pollutants) are quite high in all tissues regardless of fish species. Moreover, it has emerged that these two fish species are suitable for monitoring microplastics in the study area.
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    Monthly monitoring of length-weight relationships of allis shad (Alosa immaculata Bennett, 1835), horse mackerel (Trachurus mediterraneus Steindachner, 1868) and sprat (Sprattus sprattus Linnaeus, 1758) from the Southern Black Sea, Turkey
    (Cahiers De Biologie Marine, 2015) Ozdemir, Suleyman; Erdem, Ercan; Ozdemir, Zekiye Birinci; Aksu, Hakan
    Length-weight relationships are presented monthly for allis shad (Alosa immaculata), horse mackerel (Trachurus mediterraneus) and sprat (Sprattus sprattus) sampled with a commercial pelagic trawl vessel at depths ranging from 20 to 80 m between October 2008 and May 2009 in Black Sea, Turkey. The mean monthly values of the exponent b of the length-weight relationships ranged from 3.043 to 3.658 for allis shad, from 3.016 to 3.357 for horse mackerel and from 2.813 to 3.253 for sprat. Taking into account monthly confidence intervals, the length-weight relationships generally indicated a positive allometric growth in allis shad but an isometric growth in February, April and May 2009; it indicated a positive allometric growth in horse mackerel except in November and December 2008 (isometric growth), whereas it denoted isometric growth in sprat in October 2008, negative allometric growth from November 2008 to February 2009, isometric growth again in March 2009 and positive allometric growth in April and May 2009. Results showed that b value of allis shad, horse mackerel and sprat varied with season in the Black Sea.
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    Population abundance and growth parameters of an exotic bivalve species, Anadara kagoshimensis, in the Southwestern Black Sea
    (Tubitak Scientific & Technological Research Council Turkey, 2023) Dagtekin, Murat; Dalgic, Goktug; Erbay, Murat; Akpinar, Ilkay Ozcan; Aydin, Mehmet; Ozdemir, Suleyman; Cebeci, Ayse
    Blood cockle (Anadara kagoshimensis ) is an Indo-Pacific species that later entered the Black Sea. The abundance of A. kagoshimensis, which is not subjected to commercial fishing, is important in terms of food competition with other bivalvia species. Baby clam (Chamelea gallina) together with the A. kagoshimensis are dominant bivalve species found in the sandy and muddy areas off the coastal waters of the Black Sea. In this study, specimens of A. kagoshimensis have been recognized by morphological analysis and also confirmed by molecular characterization. Furthermore, the abundance and growth parameters of A. kagoshimensis were investigated in the Southwestern Black Sea. Blood cockles were sampled between February 2011 and December 2012, seasonally. According to the Von Bertalanffy Growth Parameters (VBGP) the results were L infinity = 81.96 mm, K = 0.32 year-1, t0 = -0.22 year, and nonseasonal L infinity = 84.32 mm, K = 0.31 year-1, t0 = -0.21, WP = 0.65, ts = 0.15. The growth pattern showed the slope [b] = 2.96-3.01 in 2011 and 2012. The stock size was estimated according to two different years in 5 different subareas (Cide, Inebolu, Turkeli, Ayancik, and Sarikum) and by 4 different strata (0-5 m, 5-10 m, 10-15 m, and 15-20 m). Considering subareas, the A. kagoshimensis population in all subareas increased significantly in a single year. Compared to other regions, Inebolu was the main highly distributed area of the A. kagoshimensis, and also the estimated stock size was the highest in the region. Due to food competition with other commercial species (mainly Chamelea gallina) A. kagoshimensis is an ecology important species for the Southern Black Sea habitats. It is aimed to make contributions to Good Environmental Status (GES) and fisheries management in the region.
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    Preliminary study of A Bycatch of pelagic trawl fishery in the southern Black Sea Coast of Turkey: Moon jellyfish Aurelia aurita
    (Natl Inst Science Communication-Niscair, 2014) Ozdemir, Suleyman; Erdem, Ercan; Birinci-Ozdemir, Zekiye
    Present study was carried out in Southern Black Seaduring October 2008 and total 22 midwater trawl nets were towed.Horse mackerel (Trachurusmediterraneus) and moon jellyfish (Aurelia aurita)were caught by midwater trawl12 768 kg and 6415 kg respectively in the experiments. There are significant differences onthe mean length of horse mackerel in the hauls (p<0.05).Deadjellyfishcan increase the riskof pollutionin the Black Sea which is incidentalcaptured by the nets.
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    Seasonal abundance estimates of cetaceans in the southern Black Sea (Sinop), Türkiye
    (Wiley, 2024) Ozsandikci, Ugur; Ozdemir, Suleyman
    The availability of reliable information on the abundance and distribution of threatened species is fundamental to evaluating their conservation status and taking the necessary measures to implement effective management. The seasonal abundance and distribution of cetaceans in the Sinop region, one of the essential fishing areas of the Black Sea, were estimated with line-transect data. Dedicated boat-based visual observations were conducted in four seasons between May 2019 and March 2020. Average estimates of abundance in the region over all seasons were 1,058 individuals for Black Sea harbor porpoises (Phocoena phocoena relicta; CV = 19.25%, 95% CI[725, 1,542]), 188 individuals for Black Sea bottlenose dolphins (Tursiops truncatus ponticus; CV = 21.67%, 95% CI[123, 289]), and 311 individuals for Black Sea common dolphin (Delphinus delphis ponticus; CV = 16.77%, 95% CI[123, 427]). The highest estimates for all three species were obtained in the spring. Harbor porpoises and bottlenose dolphins were present in the study area throughout the year, while common dolphins left the region in winter. These findings offer valuable insights that can guide and inform future conservation strategies, aligning with national and international frameworks for the protection of these cetacean species.
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    Seasonal Variation in Biochemical Composition of the Veined Rapa Whelk, Rapana venosa (Valenciennes, 1846) Caugth By Beam Trawl (Algarna) in The Black Sea
    (Centivens Inst Innovative Research-Ciir, 2016) Bayrakli, Baris; Ozdemir, Suleyman; Duyar, Hunkar Avni
    This study was conducted to determine the seasonal variation in biochemical composition of the veined rapa whelk, Rapana venosa caugth by beam trawl (Algarna) in the Blach Sea. R. venosa samples were obtained from fishermen who fishing off Yakakent at Samsun province in the Black Sea between December 2014 and November 2015. Homogenised dired veined rapa whelk meats were used for crude protein, crude oil and crude ash analyzes. Mean crude ash values was the highest in winter (2.91 +/- 0.134%) and the lowest in spring (2.37 +/- 0.051%) (P<0.05). The mean lipid values were not statistically difference among the seasons (one way ANOVA, P > 0.05). The mean crude protein values were also not statistically difference among the seasons (P>0.05). Mean dry matter values was the highest value in winter (31.33 +/- 0.448%) and the lowest in spring (30.01 +/- 0.280%). The dry matter values in winter was also statistically higher than spring (P<0.05). Food availability, plankton composition, temperature, reproduction activities, analysed tissues such as gonad, digestive gland, foot and mantle are the importent factors effect the biochemical composition of rapana. Thus, these factors should be take into account in the future studies.
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    Seasonal Variations in the Length-weight Relationships of the Thornback Ray Raja clavata L., 1758 (Chondrichthyes: Rajidae) from the Turkish Black Sea Coast
    (Inst Zoology, Bas, 2021) Ozdemir, Suleyman; Ozsandikci, Ugur; Buyukdeveci, Ferhat; Erdem, Yakup
    Data on seasonal variations of the length-weight relationships of the threatened thornback ray Raja clavata L., 1758 from the Black Sea coastal areas of Turkey are presented. The study was carried out along the Sinop coasts between September 2015 and August 2016. Twelve trammel nets (32 mm, 36 mm and 40 mm mesh size) and 30 turbot gillnets (320 mm mesh size) were used. Totally, 430 thornback rays were analysed to calculate their length-weight relationship. The mean length of all thornback rays was 60.88 +/- 0.91 cm. The values of parameter b were 3.3450, 3.1496 and 3.2525 for females, males and all individuals, respectively. Positive allometric growths (t-test, p < 0.05) were recorded in all groups. The seasonal length-weight relationship of thornback rays was determined as W = 0.0029L(3.1675) (R = 0.9533, N = 323) for summer, W = 0.003L(3.1505) (R = 0.9955, N = 20) for autumn, W = 0.003L(3.1612) (R = 0.9967, N = 16) for winter and W = 0.0022L(3.2412) (R = 0.9866, N = 71) for spring.
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    Using acoustically visible gillnets to reduce bycatch of a small cetacean: first pilot trials in a commercial fishery
    (Elsevier, 2021) Kratzer, Isabella Maria Friederike; Brooks, Mollie Elizabeth; Bilgin, Sabri; Ozdemir, Suleyman; Kindt-Larsen, Lotte; Larsen, Finn; Stepputtis, Daniel
    Bycatch of protected species, particularly small cetaceans, in gillnets is a worldwide concern. One hypothesis for this is that echolocating cetaceans entangle because they do not perceive conventional gillnets as impenetrable barriers, owing to the gillnet's faint echo. A gillnet modified for improved acoustical visibility was tested in a first pilot trial in a commercial gillnet fishery targeting turbot (Scophthalmus maeoticus) on the Turkish Black Sea coast. This study is the first demonstration of the viability of using a gillnet equipped with small acrylic glass spheres to reduce bycatch of harbor porpoises in a commercial fishery and provides the basis for full-scale sea trials of the gear in commercial fisheries through a power analysis. In these pilot experiments, the focus lied on the handling of the gear and identification of requirements for a full-scale trial, but results include promising bycatch data for an endangered echolocating marine mammal (Phocoena phocoena) and no reduction in catch efficiency of a bottom-dwelling, vulnerable species (Raja clavata).