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This paper updates some information on fish catches from the last dalians (stationary uncovered pound nets) operating off the coast of Istanbul Strait. The data were collected on the weekly basis directly from the owners of the traps. Although the traps have been targeting migratory pelagic fishes during their migration, demersal species have been caught as well. Totally, 15 fish species belonging to 12 families were caught during the study period. While the number of fishing days ranged from 24 to 37, the catch per unit effort ranged from 163.08 kg/day to 456.39 kg/day. As a conclusion, this study provides recent reference for the future studies dealing with monitoring and managing dalian fishery., Bu çalışmada, İstanbul Boğazı kıyılarında faaliyet gösteren son dalyanlarda balık avcılığı hakkında bazı bilgileri güncellemektedir. Veriler haftalık olarak doğrudan dalyanların sahiplerinden alınmıştır. Dalyanlar, göçleri sırasında göçmen pelajik balıkları hedef alsalar da, demersal türler de avlanmıştır. Çalışma süresince toplam 12 familyaya ait 15 balık türü yakalanmıştır. Balıkçılık gün sayısı 24 ile 37 arasında ve birim çabadaki av miktarı 163,08 kg/gün ile 456,39 kg/gün arasında değişmektedir. Sonuç olarak, bu çalışma dalyan balıkçılığının izlenmesi ve yönetimi ile ilgili gelecekteki çalışmalar için güncel referans bulguları içermektedir

Bu çalışmada, İstanbul Boğazı kıyılarında faaliyet gösteren son dalyanlarda balık avcılığı hakkında bazı bilgileri güncellemektedir. Veriler haftalık olarak doğrudan dalyanların sahiplerinden alınmıştır. Dalyanlar, göçleri sırasında göçmen pelajik balıkları hedef alsalar da, demersal türler de avlanmıştır. Çalışma süresince toplam 12 familyaya ait 15 balık türü yakalanmıştır. Balıkçılık gün sayısı 24 ile 37 arasında ve birim çabadaki av miktarı 163,08 kg/gün ile 456,39 kg/gün arasında değişmektedir. Sonuç olarak, bu çalışma dalyan balıkçılığının izlenmesi ve yönetimi ile ilgili gelecekteki çalışmalar için güncel referans bulguları içermektedir.

Effective sustainable management of marine fisheries requires that assessed management units (that is, fish stocks) correspond to biological populations. This issue has long been discussed in the context of Atlantic bluefin tuna (ABFT, Thunnus thynnus) management, which currently considers two unmixed stocks but does not take into account how individuals born in each of the two main spawning grounds (Gulf of Mexico and Mediterranean Sea) mix in feeding aggregations throughout the Atlantic Ocean. Using thousands of genome-wide molecular markers obtained from larvae and young of the year collected at the species’ main spawning grounds, we provide what is, to the best of our knowledge, the first direct genetic evidence for “natal homing” in ABFT. This has facilitated the development of an accurate, cost-effective, and non-invasive tool for tracing the genetic origin of ABFT that allows for the assignment of catches to their population of origin, which is crucial for ensuring that ABFT management is based on biologically meaningful stock units rather than simply on catch location., Sí

The interactions between selenium (Se) and mercury (Hg) were assessed in order to interpret public health risk, associated with dietary mercury exposure due to fish consumption. For this purpose, the mass and molar concentrations of Se and Hg were determined in the edible tissues of six species of fish, collected from the commercial fishing grounds of Turkey. The Se/Hg molar ratios and selenium health benefit values (Se-HBVs) were also calculated. The main fish species exported from Turkey to Europe were studied to determine the risks or benefits for human health. The mean Hg levels (μg g−1, wet weight) ranged from 0.01 (in turbot) to 0.45 (in Atlantic bluefin tuna). The average selenium concentrations were between 0.96 μg g−1 (in thornback ray) and 1.86 μg g−1 (in turbot). The molar ratios of Se/Hg were above 1 for all species and greater than 100 in turbot, red mullet, and whiting. Positive Se-HBVs were determined for all samples, showing health benefits. Since Se is present in molar excess of Hg in the fish muscles, organic Hg exposures from eating these fish is not a public health concern.

The genetic diversity of the Mediterranean swordfish (Xiphias gladius Linneus) has not been explored extensively at its easternmost range so far. In this study, modern X. gladius samples from the eastern part of the Mediterranean basin, north of the Aegean Sea (Aegean-2013, n = 26) and the Mediterranean coast of Turkey (N.Levantine-2013, n = 42) were studied genetically, along with ancient samples from Yenikapi excavation (n = 6). Partial mitochondrial DNA control region sequences (entire sequences, clade I and clade II) were evaluated spatially and temporally together with previously published sequences (Alvarado Bremer et al., Molecular Phylogenetics and Evolution, 2005, 36, 169-187; Vinas et al., ICES Journal of Marine Science, 2010, 67, 1222-1229; Righi et al., Diversity, 2020, 12, 170) from the rest of the Mediterranean Sea. Pair-wise FST and pair-wise AMOVA tests showed that, in general, groups of eastern populations and western Mediterranean populations have not genetically differed from each other significantly nearly in the past 20 years. Therefore, the results direct reconsideration of previous descriptions of population sub-structure within the Mediterranean and support high gene flow throughout the region. On the contrary, the results of this study confirmed the existence of genetic diversity differences between western and eastern Mediterranean, with eastern being low. One-tailed permutation tests revealed that θ, which is directly proportional to long-term female effective population size (Ne), decreased significantly (P

The share of Bluefin Tuna (BFT) has gained in importance in world fishing and trade for the last 50 years. Particularly in the Mediterranean region, this capture-based aquaculture (farming and fattening) activity has reached an important potential. This study examined the effects of toxic metals and omega-3 fatty acids from BFT fish captured in the Mediterranean Sea and cultured in the Aegean Sea on human health. The results of the current research revealed that the different groups of BFT (medium and large) fishes in general were rich in omega-3 fatty acids (especially from EPA and DHA) and hypocholesterolemic/Hypercholesterolemic potential (h/H) is higher than 3. The consumption of BFT products will reduce the cardiovascular risks. However, due to THQ (>= 1), it has been found that mercury may cause serious health problems to the community in the long term.

Bu calismada, Bati Karadeniz dip trol balikciliginin genel karakteri ile cekim suresi, hedef, iskarta ve toplam av miktari gibi bazi parametreler arasi iliskiler regresyon ve korelasyon analizi ile incelenmistir. Calisma verileri Igneada ve Rumeli Feneri bolgelerinde 2012-2014 yillari arasinda 66 gecerli dip trol cekiminden elde edilmistir. Sonuc olarak 2010-2014 yillari arasinda dip trol balikcilarinin denize ciktiklari gun sayisi 99 ile 167 arasinda degistigi tespit edilmistir. Cekim suresi arttikca toplam av artarken iskarta av miktari da artmaktadir. Karadeniz demersal kaynaklarinin surdurulebilir kullaniminin saglanmasi icin yalnizca karaya cikan av uzerinden duzenlemeler yapmak yerine balikcilik girdi kontrollerinin de (denize cikilan gun sayisi ve cekim suresi gibi) balikcilik yoneticileri tarafindan planlanmasi gerekmektedir.

Bu çalışmada, Batı Karadeniz dip trol balıkçılığının genel karakteri ile çekim süresi, hedef, ıskarta ve toplam av miktarı gibi bazı parametreler arası ilişkiler regresyon ve korelasyon analizi ile incelenmiştir. Çalışma verileri İğneada ve Rumeli Feneri bölgelerinde 2012-2014 yılları arasında 66 geçerli dip trol çekiminden elde edilmiştir. Sonuç olarak 2010-2014 yılları arasında dip trol balıkçılarının denize çıktıkları gün sayısı 99 ile 167 arasında değiştiği tespit edilmiştir. Çekim süresi arttıkça toplam av artarken ıskarta av miktarı da artmaktadır. Karadeniz demersal kaynaklarının sürdürülebilir kullanımının sağlanması için yalnızca karaya çıkan av üzerinden düzenlemeler yapmak yerine balıkçılık girdi kontrollerinin de (denize çıkılan gün sayısı ve çekim süresi gibi) balıkçılık yöneticileri tarafından planlanması gerekmektedir.

The potential human health risks of copper (Cu), zinc (Zn), arsenic (As), cadmium (Cd), mercury (Hg) and lead (Pb) in Thunnus thynnus from the northern Levantine Sea were assessed. The mean concentrations (mg/kg) of metals were found as 0.819 for Cu, 8.344 for Zn, 2.102 for As, 0.002 for Cd, 0.001 for Hg and 0.115 for Pb. Even though these values were below the permitted levels, 11% of the samples contained Pb above the limits. Estimated weekly intakes were conspicuously lower than the PTWI values. The target hazard quotients (THQs) of each metal and total THQ of combined metals remained well below 1, showing no public health risk for an average consumer.

The common two-banded seabream Diplodus vulgaris and Diplodus sargus were sampled from non-commercial fishing catches around the Maltese Islands between July 2012 and December 2017. A total of 1550 (D. vulgaris N=1204, D. sargus N=346) specimens were collected. In this study, age, growth, length-weight relationship (LWR), condition factor (K) and relative condition factor (Kn) were investigated. Ages ranged from 0 to 17 years for D. sargus and 0 to 16 years for D. vulgaris. A positive allometric growth was observed for D. sargus while growth in D. vulgaris was isometric. Average Kn was found to be 0.99 and 1.01 in D. vulgaris and 0.97 and 1.00 in D. sargus for males and females respectively. The growth parameters of the von Bertalanffy equation were: L∞=26.71 and 30.86 cm, K= 0.275 and 0.286 year-1 and tₒ = -2.27 and -1.61 year for all individuals of D. vulgaris and D. sargus respectively. This study is the first reference on the LWR equation parameters, Kn, K and Age for these species around the Maltese Islands and establishes a new maximum age for D. vulgaris of 16 years., peer-reviewed

Bu çalışmayla, İstanbul kıyı balıkçılığında kullanılan pelajik uzatma ağlarının teknik özellikleri tespit edilmiştir. Bölgede iki adedi fanyalı ve beş adedi sade olmak üzere toplam yedi tip pelajik uzatma ağı tanımlanmıştır. Bu uzatma ağlarının teknik planları FAO standartlarına göre ilk defa tanıtılmıştır

Bu çalışmada, 1987-2012 yılları arasında orkinos gırgır av filosunda bulunan gemi sayısı, gemi boyları, gros tonajı, motor güçleri ve tüm bu özelliklerin yıllara göre değişimleri incelenmiştir. Balıkçı gemilerin ortalama gros tonajın yıllara göre değişimi incelendiğinde, gittikçe artan bir eğilim gözükmektedir. Balıkçı gemilerinin gros tonajı (GRT) ve tam boyu (LOA) ile gros tonajı (GRT) ve makine gücü (HP) arasında yüksek korelasyona sahip üssel bir ilişki olduğu saptanmıştır

The common dolphinfish (Coryphaena hippurus) is an epipelagic, mid-trophic level, highly migratory species distributed throughout the world’s tropical and subtropical oceans in waters greater than 20°C. Life-history variables, migratory behaviour, and genetic markers have been used to define major stocks in the central Atlantic Ocean and Mediterranean Sea. Here, we used the mitochondrial DNA gene NADH subunit 1 (688 bp) to test for differences between population groups. A total of 103 haplotypes were detected among 203 fish. Gene diversities in samples were large and similar among populations (mean h = 0.932; range 0.894–0.987), but nucleotide diversities varied widely among samples (range π = 0.004–0.034) and appear to reflect population histories. Principal component analysis revealed two large populations groups, and the analysis of molecular variation and pairwise values of ΦST resolved population structure within these groups. Populations in the eastern Atlantic and Mediterranean showed the largest amounts of divergence from one another (ΦCT = 0.331). Adult movement and biophysical barriers to larval dispersal may explain contemporary differences between stocks, but the divergent populations in the Mediterranean Sea are likely due to isolations by cold temperature barriers during Pleistocene glaciations. The geographically large stock groupings require international cooperation in the harvest management and conservation of local dolphinfish populations.

In this review, the mechanism of action of poisons and toxic effects of and treatment methods for the same among weever fishes, which are present along the coast of Turkey, were addressed. Weever fish poison is present in the spicule located on the operculum and in the 5th-8th dorsal spines located on the first dorsal fin. Weever fish poisoning is identified through symptoms of intense pain, burning, and stinging. The duration of these symptoms varies among patients and depends on the species and season. Contrary to common belief, instead of immersion in cold water, immersion in hot water at about ≥40°C is used during emergencies., Bu derleme çalışmasında ülkemiz kıyılarında dağılım gösteren trakonya balıklarının zehir ve toksik etki mekanizmaları ile tedavi yolları irdelenmiştir. Trakonya zehri, solungaç kapağı üzerinde bulunan operküler dikende ve 1.dorsal yüzgeçte bulunan 5-8 dorsal dikende bulunur. Trakonya zehirlenmeleri ani bir ağrı, yanma ve iğneleme şeklinde ortaya çıkmaktadır. Bu bulguların süresi hastaya, balığın cinsine ve mevsimlere göre değişmektedir. Halk arasında bilinenin aksine acil servis müdahalesi olarak soğuk su yerine etkilenen bölgenin 60-90 dakika yaklaşık 40oC veya daha sıcak suya daldırılması gerekmektedir.

Available knowledge on the assemblage patterns of demersal macro-faunal species in the Black Sea is scarce. For this reason, data series of demersal trawl surveys between 2011 and 2014 were collected to identify the demersal assemblages along the continental shelf in the southwestern Black Sea. Data were analysed from 146 demersal trawl hauls conducted in the spring and autumn periods for three bathymetric contours: 0–20 m, 20–50 m, and 50–100m. The spatial and temporal structural patterns of demersal zonation were assessed using multivariate analyses. Out of a total of 78 taxa, 69 demersal species were identified. Fishes showed the highest diversity with 41 species followed by 16 mollusks, 11 crustaceans, 5 echinoderms, 1 tunicate, and 1 porifera. Multivariate analyses revealed significant differences in the assemblages according to depth, sub-region, season, and year. Statistically, depth was the most influential factor determining the ordination of the faunal zonation. This study concludes that Merlangius merlangus, Mullus barbatus, Mytilus galloprovincialis, and Liocarcinus depurator may be the indicator species that make the greatest contribution to the formation of the demersal macro-community.

Bu çalışma, İstanbul Boğazı’nda kurulan kaldırma ağlarının mevkileri, ağların teknik özellikleri, balıkçılık durumlarını ve hedef türleri belirlemek amacıyla yapılmıştır. İstanbul Boğazı’nda iskele ve kıyılarda kurulan üç adet kaldırma ağı (Arnavutköy, Yeniköy ve Tarabya) bulunduğu tespit edilmiştir. Kurulan kaldırma ağları, taşıyıcı direkler veya kaldıraç sistemine göre çalışmaktadır. Araştırma süresince kaldırma ağlarında rastlanılan balık türleri; gümüş (Atherina boyeri), kefal (Mullet sp.) ve zargana (Belone belone)’dır

The Atlantic bluefin tuna, Thunnus thynnus, is a commercially important species that has been severely over-exploited in the recent past. Although the eastern Atlantic and Mediterranean stock is now showing signs of recovery, its current status remains very uncertain and as a consequence their recovery is dependent upon severe management informed by rigorous scientific research. Monitoring of early life history stages can inform decision makers about the health of the species based upon recruitment and survival rates. Misidentification of fish larvae and eggs can lead to inaccurate estimates of stock biomass and productivity which can trigger demands for increased quotas and unsound management conclusions. Herein we used a molecular approach employing mitochondrial and nuclear genes (CO1 and ITS1, respectively) to identify larvae (n = 188) collected from three spawning areas in the Mediterranean Sea by different institutions working with a regional fisheries management organization. Several techniques were used to analyze the genetic sequences (sequence alignments using search algorithms, neighbour joining trees, and a genetic character-based identification key) and an extensive comparison of the results is presented. During this process various inaccuracies in related publications and online databases were uncovered. Our results reveal important differences in the accuracy of the taxonomic identifications carried out by different ichthyoplanktologists following morphology- based methods. While less than half of larvae provided were bluefin tuna, other dominant taxa were bullet tuna (Auxis rochei), albacore (Thunnus alalunga) and little tunny (Euthynnus alletteratus). We advocate an expansion of expertise for a new generation of morphology-based taxonomists, increased dialogue between morphology-based and molecular taxonomists and increased scrutiny of public sequence databases., SI

Atlantic bluefin tuna (ABFT) fattening activities began in the eastern Mediterranean (Cyprus, Greece, and Turkey) in 2002. The total potential production is estimated at 11,240 tons. However, the actual production fluctuates depending on catch quota. ABFT farming in the region uses traditional methods of catching tuna with purse seiners and transferring them to grow-out cages, where they are fed small pelagic fishes until they reach the size and fat level required by the high-end market. ABFT farming in the region has had some conflicts with other human activities such as tourism. The boom in tuna farming in the Mediterranean over a relatively short period of time has caused overfishing, which in turn has led to a decreasing spawning stock. The ABFT has disappeared from the Black Sea, and their spawning ground in the eastern Mediterranean needs to be regulated and protected to ensure the long-term sustainability of the stock. Illegal, Unreported and Unregulated (IUU) fishing practices should be strictly regulated by the International Commission for the Conservation of Atlantic Tunas (ICCAT) members and nonmember countries. The development of hatchery and sustainable aquaculture technologies will decrease the pressure on wild stocks and in the future may enable stock enhancement, mitigating overfishing, and decreasing the high market price of the ABFT in the eastern Mediterranean and elsewhere.

The original version of this article unfortunately contained mistakes. Under section, ‘Estimated Weekly Intake (EWI),’ the value 150 g should be corrected as 100 g in the sentences ‘The weekly consumption value for fish…’ and ‘where WFC is the weekly fish consumption …’. Likewise under section, ‘Target Hazard Quotient (THQ),’ the data (21.43 g/person/day) should be (14.26 g/person/day).

Bu çalışmayla, İstanbul kıyı balıkçılığında kullanılan dip uzatma ağlarının teknik özellikleri tespit edilmiştir. Bölgede altı adedi fanyalı ve yedi adedi sade olmak üzere toplam 13 tip dip uzatma ağı tanımlanmıştır. Bu uzatma ağlarının teknik planları FAO standartlarına göre ilk defa tanıtılmıştır

In this study, the stomach contents of 116 albacore specimens, Thunnus alalunga were examined from the eastern Mediterranean Sea. Fifty-five of the 116 stomachs examined were empty. The occurrence of major prey categories in stomachs were 95.1% cephalopods, 47.5% teleosts and 39.3% crustaceans with a total of 633 individuals belonging to 14 species identified. Heteroteuthis dispar from the order Sepiolida constituted 56.40% of the main cephalopod prey followed by Onychoteuthis banksii from the order Teuthida.

Fishing trials were carried out with gill nets and trammel nets in the northern Aegean Sea from March 2004 to February 2005. Four different mesh sizes for the gill nets and the inner panel of trammel nets (16, 18, 20 and 22 mm bar length) were used. Selectivity parameters for the five most economically important species, bogue (Boops boops), annular sea bream (Diplodus annularis), striped red mullet (Mullus surmuletus), axillary sea bream (Pagellus acarne) and blotched picarel (Spicara maena), caught by the two gears were estimated. The SELECT method was used to estimate the selectivity parameters of a variety of models. Catch composition and catch proportion of several species were different in gill and trammel nets. The length frequency distributions of the species caught by the two gears were significantly different. The bi-modal model selectivity curve gave the best fit for gill net and trammel net data, and there was little difference between the modal lengths of these nets. However, a clear difference was found in catching efficiency. The highest catch rates were obtained with the trammel net. Given that many discard species and small fish are caught by gill nets and trammel nets with a mesh size of 16 mm, it is clear that these nets are not appropriate for fisheries. Consequently, the best mesh size for multispecies fisheries is 18 mm. This mesh size will considerably reduce the numbers of small sized individuals and discard species in the catch. Se realizaron ensayos de pesca con betas y trasmallos en el Egeo septentrional desde marzo de 2004 a febrero de 2005. Se utilizaron cuatro luces de malla distintas (16, 18, 20 y 22 mm) tanto para las betas como para el paño interno de los trasmallos. Se estimaron los parámetros de selectividad de las cinco especies más importantes capturadas por ambos artes: boga (Boops boops), raspallón (Diplodus annularis), salmonete de roca (Mullus surmuletus), aligote (Pagellus acarne) y chucla (Spicara maena). Se utilizó el método SELECT para la estimación de los parámetros de selectividad de varios modelos. La composición en tallas de la captura así como la proporción de las distintas especies capturadas por las betas y trasmallos fueron diferentes. La distribución de frecuencias de tallas de las especies capturadas por ambos artes fueron significativamente diferentes. El modelo de curva de selectividad bimodal fue el que mejor se ajustó a los datos de betas y trasmallos, y se encontraron muy pocas diferencias entre las longitudes modales de ambos artes. No obstante, se encontró una diferencia clara en la eficiencia de captura. Las tasas de captura más altas correspondieron a los trasmallos. Teniendo en cuenta que con betas y trasmallos de luz de malla de 16 mm se obtienen muchas especies que son posteriormente descartadas así como gran cantidad de peces pequeños, parece claro que estas redes no son convenientes para la pesquería. La luz de malla de 18 mm es la mejor para estas pesquerías multiespecíficas. El uso de paños con esta luz de malla resultaría en una reducción considerable del número de individuos de pequeña talla así como de las especies descartadas.

Data on technical specifications, numbers, catch, fishing power per boat and CPUE of purse-seining boats for the tuna fishery in the Turkish waters between 1994 and 2000 periods are presented. The number of the purse-seining boats operating during the period varied between 22 and 62. In recent years, the bluefin fishing fleet and the fishery have been transformed. The fleet now consists of larger boats with more powerful engines, bigger fishing nets, and the use of sophisticated electronics like echosounders, sonars and sea bird radars. Those factors combined with the increased captain’s experience and skill in using the technologies are important factors that have resulted in significant changes in the traditional measures of effectiveness of the Turkish tuna fishery.

Assessment and management of Atlantic bluefin tuna Thunnus thynnus populations is hindered by our lack of knowledge regarding trans-Atlantic movement and connectivity of east- ern and western populations. Here, we evaluated migratory and homing behaviors of bluefin tuna in several regions of the North Atlantic Ocean and Mediterranean Sea using chemical tags ( δ 13 C and δ 18 O) in otoliths. Significant emigration of bluefin tuna from their place of origin was inferred from otolith δ 13 C and δ 18 O, with both eastern and western bluefin tuna commonly ‘crossing the line’ (45° W management boundary) in the Central North Atlantic Ocean and mixing with the other population. Several western migrants were also detected in Moroccan traps off the coast of Africa, indicating that trans-Atlantic movement occurs for members of the western population; however, the degree of mixing declined with proximity to the eastern spawning area (Mediterran- ean Sea). The origin of bluefin tuna collected at the entrance to the Strait of Gibraltar and from several regions within the Mediterranean Sea (Balearic Islands, Malta, and Sardinia) was essen- tially 100% eastern fish, demonstrating that natal homing is well developed by the eastern popu- lation, with western migrants rarely entering the Mediterranean Sea., SI

Two stocks of bluefin tuna (Thunnus thynnus) inhabit the north Atlantic; the western and eastern stocks spawn in the Gulf of Mexico and the Mediterranean Sea respectively. Trans-Atlantic movements occur outside spawning time whereas natal homing maintains stock structure. Commercial fisheries may exploit a mixed assemblage of both stocks. The incorporation of mixing rates into stock assessment is precluded by uncertainties surrounding stock discrimination. Otolith shape descriptors were used to characterise western and eastern stocks of Atlantic bluefin tuna in the present study and to estimate stock composition in catches of unknown origin. Otolith shape varied with length and between locations and years. Within a restricted size range (200–297-cm fork length (FL)) the two stocks were distinguished with an accuracy of 83%. Bayesian stock mixture analysis indicated that samples from the east Atlantic and Mediterranean were predominantly of eastern origin. The proportion assigned to the eastern stock showed slight spatial variation; however, overlapping 95% credible intervals indicated no significant difference (200–297cm FL: central Atlantic, 73–100%; Straits of Gibraltar, 73–100%; Morocco, 50–99%; Portugal 64–100%). Otolith shape could be used in combination with other population markers to improve the accuracy of mixing rate estimates for Atlantic bluefin tuna.

The fish speciesSymphodus bailloni(Valenciennes, 1839) reported in the present study were collected between June 2010 and June 2011 from the western Black Sea coasts which were previously not recorded from the Black Sea coast of Turkey. A total of 717 specimens ofS. bailloniwere measured, ranging between 8.9 and 15.4 cm TL. Morphometrics, meristics, and diagnostic characteristics of the species are presented.

FAO, sürüklenen pelajik uzatma ağlarını “genellikle yüzeye yakın veya orta suda akıntıyla sürüklenen, üst yakasında yüzdürücü alt yakasında ağırlıklarıyla az veya çok düşey düzlemde kalan bir seri solungaç ağları” olarak tanımlamıştır. Özellikle deniz memelileri, deniz kuşları, deniz kaplumbağaları vb. hedef dışı av oranlarının yüksekliğine bağlı olarak sürüklenen pelajik uzatma ağları üzerine ulusal ve uluslararası düzenleme ve yasakların mevcudiyetine rağmen, Akdeniz’de kılıç balıkları için bu ağlar halen illegal olarak kullanılmaktadır. Bu çalışma, Türkiye sularında kullanılan sürüklenen pelajik uzatma ağlarının teknik özelliklerini ve ulusal ve uluslararası yasal düzenlemelerini rapor etmektedir. Dört adedi büyük ölçekli, sekiz adedi ise küçük ölçekli balıkçılıktan olmak üzere toplam 12 adet pelajik uzatma ağı tanımlanmıştır. Ağların uzunlukları 400 m ile 6900 m arasında değişmektedir., Driftnets, used in Turkish Seas and the regulations. Driftnets are defined by FAO as a fishing gear “consisting of a string of gillnets kept more or less vertical by floats on the upper line and weights on the lower line, drifting with the current, in general near surface or in mid-water.” Large scale drift nets for swordfish are still used illegally in the Mediterranean, though there are many of national-international regulations and bans on driftnets due to high ratio of by-catch, especially marine mammals, seabirds, sea turtles, etc. This study reports the technical characteristics and regulations (both national and international) of driftnets in Turkish waters. A total of 12 various type driftnets of which four from large scale and the others from small scale fisheries. The length of driftnets were ranged from 400 m to 6900 m.

WOS: 000373863800003, An ecological niche modelling (ENM) approach was used to predict the potential feeding and spawning habitats of small (5-25 kg, only feeding) and large (>25 kg) Atlantic bluefin tuna (ABFT), Thunnus thynnus, in the Mediterranean Sea, the North Atlantic and the Gulf of Mexico. The ENM was built bridging knowledge on ecological traits of ABFT (e.g. temperature tolerance, mobility, feeding and spawning strategy) with patterns of selected environmental variables (chlorophyll-a fronts and concentration, sea surface current and temperature, sea surface height anomaly) that were identified using an extensive set of precisely geo-located presence data. The results highlight a wider temperature tolerance for larger fish allowing them to feed in the northern high chlorophyll levels latitudes up to the Norwegian Sea in the eastern Atlantic and to the Gulf of Saint Lawrence in the western basin. Permanent suitable feeding habitat for small ABFT was predicted to be mostly located in temperate latitudes in the North Atlantic and in the Mediterranean Sea, as well as in subtropical waters off north-west Africa, while summer potential habitat in the Gulf of Mexico was found to be unsuitable for both small and large ABFTs. Potential spawning grounds were found to occur in the Gulf of Mexico from March April in the south-east to April May in the north, while favourable conditions evolve in the Mediterranean Sea from mid-May in the eastern to mid-July in the western basin. Other secondary potential spawning grounds not supported by observations were predicted in the Azores area and off Morocco to Senegal during July and August when extrapolating the model settings from the Gulf of Mexico into the North Atlantic. The presence of large ABFT off Florida and the Bahamas in spring was not explained by the model as is, however the environmental variables other than the sea surface height anomaly appeared to be favourable for spawning in part of this area. Defining key spatial and temporal habitats should further help in building spatially-explicit stock assessment models, thus improving the spatial management of bluefin tuna fisheries. (C) 2016 The Authors. Published by Elsevier Ltd.