Northern Aegean Sea Research Articles

Spatial and Developmental Policy Directions Affecting Marine Spatial Planning in the Northern Aegean Sea, Greece

Spatial and Developmental Policy Directions Affecting Marine Spatial Planning in the Northern Aegean Sea, Greece

Poziomy zewnętrznych dawek promieniowania gamma w wybranych miejscach w Rumunii, Mołdawii i Grecji

The study presents a synthesis of results obtained in the frame of international cross-border projects, implemented in partnership, for gamma radiation dose rates measured in outdoor environments in various sites in Romania, Moldova, Greece, including urban, rural, touristic and protection areas. The selected sites (n=41) are found in the Eastern Carpathians Mountains, Lower Danube basin, Danube Delta, Lower Prut River Reserve, Dniester River, as well as Black Sea and Northern Aegean Sea basins. The data recorded for targeted spots using portable dosimeters highlight an hourly and daily variation of the outdoor gamma dose rate and the specificity of the geological background and terrain utilization. The mean values of outdoor gamma radiation dose rate, calculated for 50 measurements per each site, are ranging between 71 nGy/h (Vama Veche, Constanta County, Black Sea coast, Romania) and 394 nGy/h (Nea Peramos, Ammolofoi beach, Northern Aegean Sea, Greece), with a minimum of 41 nGy/h in Vama Veche and a maximum of 489 nGy/h in Ammolofoi beach. A comparison is made with legislated values and other world places. The measurements performed at water surface during boat expeditions (n=21) on Danube River and Danube Delta lakes and channels point out lower values of dose rate, due to the weak influence of gamma rays’ emission from bottom sediments. The data of the dose rate temporal variations will be used for the target regions as a base in further investigations and preparation of maps of gamma dose rates (terrestrial and cosmic), and calculation of the health risk for inhabitants and tourists.

Oxynoemacheilus fatmae, a new species from the Güzelhisar Stream in the Aegean Sea basin, Türkiye (Teleostei: Nemacheilidae).

Oxynoemacheilus fatmae, a new species, is found in the Güzelhisar Stream in the northern Aegean Sea basin. It is differentiated from all other species of Oxynoemacheilus in the northern Aegean Sea and adjacent basins by having four to eight irregularly shaped narrow black bars on the posterior part of flank, and anterior parts of the flank with a marbled pattern. O. fatmae is differentiated from the closest species Oxynoemacheilus theophilii by having 14 fixed diagnostic nucleotide substitution sites, and the pair-wise genetic distance is 2.22%. It further differs from O. theophilii by having a slenderer body (body at dorsal-fin origin: 15%-17% standard length [SL] vs. 17%-18%), a slenderer caudal peduncle (10%-12% SL vs. 12%-13%), a more forked caudal fin (length of middle caudal-fin lope: 16%-19% SL vs. 19%-23%), and the absence the dorsal and ventral adipose crests on the caudal peduncle behind the vertical of the posterior anal-fin base (vs. present). Three species delimitation tests (assemble species by automatic partitioning (ASAP), automatic barcode gap discovery (ABGD) and generalized mixed yule-coalescent (GMYC)) and phylogenetic analyses reinforce the validity of O. fatmae as a distinct species.

Atlas of phytoplankton phenology indices in selected Eastern Mediterranean marine ecosystems.

Phytoplankton is a fundamental component of marine food webs and play a crucial role in marine ecosystem functioning. The phenology (timing of growth) of these microscopic algae is an important ecological indicator that can be utilized to observe its seasonal dynamics, and assess its response to environmental perturbations. Ocean colour remote sensing is currently the only means of obtaining synoptic estimates of chlorophyll-a (a proxy of phytoplankton biomass) at high temporal and spatial resolution, enabling the calculation of phenology metrics. However, ocean colour observations have acknowledged weaknesses compromising its reliability, while the scarcity of long-term in situ data has impeded the validation of satellite-derived phenology estimates. To address this issue, we compared one of the longest available in situ time series (20 years) of chlorophyll-a concentrations in the Eastern Mediterranean Sea (EMS), along with concurrent remotely-sensed observations. The comparison revealed a marked coherence between the two datasets, indicating the capability of satellite-based measurements in accurately capturing the phytoplankton seasonality and phenology metrics (i.e., timing of initiation, duration, peak and termination) in the studied area. Furthermore, by studying and validating these metrics we constructed a satellite-derived phytoplankton phenology atlas, reporting in detail the seasonal patterns in several sub-regions in coastal and open seas over the EMS. The open waters host higher concentrations from late October to April, with maximum levels recorded during February and lowest during the summer period. The phytoplankton growth over the Northern Aegean Sea appeared to initiate at least a month later than the rest of the EMS (initiating in late November and terminating in late May). The coastal waters and enclosed gulfs (such as Amvrakikos and Maliakos), exhibit a distinct seasonal pattern with consistently higher levels of chlorophyll-a and prolonged growth period compared to the open seas. The proposed phenology atlas represents a useful resource for monitoring phytoplankton growth periods in the EMS, supporting water quality management practices, while enhancing our current comprehension on the relationships between phytoplankton biomass and higher trophic levels (as a food source).

Estimación de parámetros poblacionales seleccionados para salmonetes de aguas marinas turcas Mullus barbatus ponticusEssipov, 1927 (Actinopterygii: Perciformes: Mullidae)

In order to calculate the length–weight and length–to–length relationships for red mullet Mullus barbatus ponticus Essipov, 1927 in Turkish marine waters, samples were collected from the Marmara Sea, the Northern Aegean Sea and the Western Black Sea by trawler from 2013 through 2016 fishing season. In the study in which 1,756 individuals were sampled, the number and proportion of individuals obtained from the Western Black Sea Region was 9.7% with 171 individuals from Amasra and 65.3% with 1,148 individuals from Ereğli; it was 1.7% with 30 individuals from the Marmara Sea, while it was 23.2% with 407 individuals from the North Aegean Sea. The total length was 6.3 to 20.5 cm, while the weight ranged from 2.54 to 89.53 g. In addition, 49 length–weight relationship values were examined from the literature of red mullet sampled in Turkish marine waters from 1977 to 2017. The smallest b value was determined as 2.84 from Iskenderun Bay and the highest was 3.3916 from the Izmir Bay. The median value of b was 3.188; it was observed that 50% of the b values ranged from 3.092 to 3.26.

Additional Record of Rare Pilot Fish, Naucrates ductor (Linnaeus, 1758) with Some Biological Notes from the Northern Aegean Sea, Türkiye

In this study, four individuals of pilot fish Naucrates ductor which were accidentally caught by a commercial purse seiner in Edremit Bay (Aegean Sea) were investigated. The morphometric and meristic characteristics, sex, maturity stages, otoliths, age and stomach contents of the specimens were evaluated. This study contributes to the existing literature by providing additional records from specimens reported from the northernmost location reported so far as well as other biological information for the rarely observed pilotfish.

Fish assemblages along a bathymetric gradient in the northern Aegean Sea: An ecomorphological approach

Morphological studies of fish assemblages are a crucial aspect of ecology, as they can provide insight into functional roles and changes beyond taxonomically oriented approaches. In addition, depth is an important factor that impacts the structure of fish assemblages. In the present study, samples of 115 demersal actinopterygian species were collected during a bottom-trawl survey conducted in the northern Aegean Sea, in the summer of 2020. The samples were collected by 65 hauls across depths ranging from 0 to 650 m. The samples were photographed, and the images were analyzed through geometric morphometric methods, by defining 27 landmarks and semilandmarks on each photo. Principal Components were estimated to construct morphospaces and between group Principal Component Analysis was used to distribute the mean body shape of each assemblage along morphological axes. Ecological, taxonomic and morphological diversity indices were then computed for each haul, and the potential effects of depth on these indices were tested with Generalized Additive models. All indices were significantly affected by depth, except for species richness, on which the effect was marginally insignificant. Concerning the morphological diversity indices, morphological disparity indices, estimated with 2 different methods, as well as the ecomorphological diversity found to increase with depth, whereas morphological richness fluctuated. Next, Generalized Linear Models were employed to examine the variations in the morphological traits of the mean shape of each formed assemblage. The results indicated that assemblages distinguished into two groups, one inhabiting the continental shelf (<200 m), and the other the upper-medium slope (>200 m). Specifically, with increasing depth, fish converge towards an elongated body, with larger mouth and eyes, but smaller pectoral fin. The findings of this study, contribute to better understanding of the impact of depth on the ecological and morphological structure of demersal assemblages, and highlight the importance of morphological diversity indices as a complement to conventional approaches.

First occurrence of rudderfish Centrolophus niger (Gmelin, 1789) in the Edremit Bay (Northern Aegean Sea, Türkiye) with the maximum length record for Turkish Seas

Climate change is one of the crucial factors affecting the geographical distribution of fish species. However, the maximum size is an indication of whether there is overfishing pressure on a fish species or the current ecological conditions in which it is located. A single specimen of recently died (rigor mortis has not yet formed) Centrolophus niger was incidentally found inshore on January 27, 2023, off the Burhaniye coast (Edremit Bay, Northern Aegean Sea, Türkiye). The present study indicates both the first observation of C. niger for Edremit Bay and its maximum length for Turkish seas.

Assessment of health risks due to toxic metals in demersal fish captured from Saros and Edremit Bays, Northern Aegean Sea.

Bays are vulnerable ecosystems generally located near densely populated areas where toxic metals tend to accumulate and stay longer, affecting marine life. This study aimed to investigate the age-based health risks arising from Hg, Cd, Pb, and As in demersal fish captured from two major bays in the Aegean Sea. For this purpose, red mullet, whiting, piper gurnard, and tub gurnard, frequently consumed species, were caught from Saros and Edremit Bays. Toxic metal concentrations were determined from the muscle tissue of fish. Health risk assessments were conducted by the estimation of weekly intake (EWI), provisional tolerable weekly intake (PTWI), target hazard quotient (THQ), total THQ (TTHQ), and target carcinogenic risk (TR). Red mullet from Edremit Bay was the species with the highest toxic metal levels, which were 1.597mg/kg, 0.041mg/kg, 0.070mg/kg, and 19.351mg/kg for Hg, Cd, Pb, and As, respectively. Whiting from Edremit Bay had higher mean concentrations of Hg and As than those from Saros Bay. The levels of Hg, Pb, and As (0.328, 0.043, and 0.574mg/kg) in the tub gurnard were higher in comparison with the piper gurnard (0.252, 0.020, and 0.382mg/kg) caught in the same station in Saros. TTHQs of red mullet and whiting from the same bay were found to be > 1, indicating potential health risks for all nine age categories studied. On the other hand, TTHQs of all species from Saros Bay were determined to be > 1 for the first four age categories, which might trigger health risks for children and adolescents. According to the TR index for Pb, no risk was determined for the fish from both bays. However, TR calculations for inorganic As indicated high cancer risk in most of the age categories for red mullet and whiting from Edremit Bay. To sum up, the results revealed that the fish captured from Edremit Bay posed serious health risks in terms of Hg and As concentrations for all nine age categories. Surveillance and monitoring of toxic metal levels in demersal fish and population-based health risk evaluation are vital in heavily populated bays.

Deriving the diffuse attenuation coefficient in the Eastern Mediterranean Sea, using observational optical measurements and a multi-layer perceptron regression model

The diffuse attenuation coefficient is an indicator of light availability in the surface layer, and is used in a broad range of applications, including numerical simulations, for the parameterization of the light transmission in the water column. In this study, a new dataset of the diffuse attenuation coefficient for the Eastern Mediterranean Sea test case is developed using an existing optical dataset of 2614 beam attenuation coefficient profiles. This method introduces a way of overcoming the difficulty of measuring the diffuse attenuation coefficient in-situ by utilizing the most routinely measured variable, the beam attenuation coefficient. The proposed approach uses existing semi-analytical relationships and a neural network. The neural network, a multi-layer perceptron regression model, is trained and validated with a dataset of 29398 concurrent bio-optical in-situ measurements from the PROSOPE cruise and remotely sensed surface variables. The model is applied to the Eastern Mediterranean dataset and the results are interpolated into a gridded gap-free field, with a grid resolution of 0.0416° x 0.0416°, which is assessed and compared with a satellite-derived product, investigating their significant differences. The resulting field's mean value is slightly reduced with respect to the satellite product, showing regions of higher turbidity, with the most prominent located in the northern Aegean Sea in regions of excess colored dissolved organic matter and around mesoscale features and in the Cretan and Levantine Sea in regions of higher mesoscale activity.

Gökçeada (Kuzey Ege Denizi) çevresindeki iki vatoz türünün, Raja miraletus Linnaeus, 1758 ve Dipturus oxyrinchus (Linnaeus, 1758) (Chondrichthyes, Rajidae) beslenme alışkanlıkları

This study investigated the feeding habits of Raja miraletus Linnaeus, 1758 and Dipturus oxyrinchus (Linnaeus, 1758). For the purpose of this study, the specimens were obtained monthly from the commercial trawlers operating around the Gökçeada Island in the Northern Aegean Sea between February 2019 and February 2020. A total of 29 (24 female and 5 male) brown rays (Raja miraletus) and 36 (20 female and 16 male) longnosed skates (Dipturus oxyrinchus) were captured. The total lengths of the R. miraletus specimens ranged between 24.0 cm and 53.9 cm, while the D. oxyrinchus specimens measured between 17.1 cm and 85.0 cm. Total length-weight relationships of R. miraletus and D. oxyrinchus specimens, respectively; W=0.0002TL3.92 (R2=0.97) and W=0.0007TL3.43 (R2=0.97) were calculated. The analysis of the stomach content of the specimens showed that crustacea were the primary and the most important prey group for R. miraletus (IRI% = 67.09), followed by teleosts (IRI% = 1.00) and cephalopods (IRI% = 0.45). The D. oxyrinchus specimens were determined to primarily feed on crustacea (IRI% = 74.3), followed by teleosts (IRI% = 6.50) and nematoda (IRI% = 0.40).

In Situ Radioactivity Maps and Trace Metal Concentrations in Beach Sands of a Mining Coastal Area at North Aegean, Greece

In recent years, the environmental effects of both active and legacy mining activity have motivated many research groups worldwide through the use of a variety of methods that have been conducted among diverse environments. In this study, we measured radionuclide concentrations at two coastline locations of the Northern Aegean Sea: Stratoni and Ierissos. We deployed KATERINA II, an in situ gamma ray spectrometer. Our results indicate that the activity concentration for 238U progenies (214Bi), 232Th progenies (208Tl and 228Ac) and 40K vary by up to (33 ± 4) Bq kg−1, (19 ± 3) Bq kg−1, and (420 ± 30) Bq kg−1, respectively. The activity concentration of the 137Cs in Stratoni and Ierissos beach sands were (8.1 ± 2.2) and (3.9 ± 1.2) Bq kg−1, respectively. Lab-based measurements were also collected prior to the in situ data collection for the determination of radionuclide and metal concentrations. The lab-based data were found to be (800 ± 40) μg g−1 and (12 ± 1) μg g−1, for As, (1200 ± 60) μg g−1 and (33.3 ± 0.3) μg g−1 for Pb, (100 ± 6) μg g−1 and (6.0± 0.3) μg g−1 for Cu and (2000 ± 60) μg g−1 and (8.0 ± 0.4) μg g−1 for Zn, respectively. We used the R language and environment for statistical computing to produce radiological maps of the subject beach sands. We used the Enrichment Factor (EF) to estimate assessment indices for the target area and compared them to internationally recommended values. The in situ maps will be discussed since the beach area of the load-out pier area of Stratoni was undergoing the first phase of active remediation. We conclude that the temporal aspect of this dataset can be of significant reference value against future comparative studies after the remediation of the Stratoni beach with potentially denser spatial and temporal data coverage.

Estimation of selectivity parameters for target and bycatch fishes of the trammel net fisheries in the northern Aegean Sea (eastern Mediterranean Sea)

The size selectivity of trammel nets was investigated in the northern Aegean Sea using 10 different inner-panel mesh sizes ranging from 16 to 70 mm nominal mesh size (bar length). Selectivity estimates were made for the eight most abundant target and bycatch fish species, namely black scorpionfish, Scorpaena porcus Linnaeus, 1758; annular seabream, Diplodus annularis (Linnaeus, 1758); red mullet, Mullus barbatus Linnaeus, 1758; surmullet, Mullus surmuletus Linnaeus, 1758; round sardinella, Sardinella aurita Valenciennes, 1847; European hake, Merluccius merluccius (Linnaeus, 1758); greater weever, Trachinus draco Linnaeus, 1758; and blotched picarel, Spicara flexuosum Rafinesque, 1810, which accounted for 51.5% by number and 42.7% by weight of the fish caught with trammel nets in the sea trials. The SELECT method was used to estimate the selectivity parameters. Five different selectivity functions (i.e., normal scale, normal location, gamma, log-normal, and bi-normal) were applied with the bi-normal function providing the best fit as it had the lowest deviance value for all species and the lowest values for the dispersion parameter ( D /df). The mesh size of 16 mm in most of the cases retained specimens below the size at first maturity ( L m ). The mesh size of 19 mm seems more appropriate for red mullet, surmullet, and blotched picarel, the mesh size of 22 mm for annular seabream and round sardinella, while for European hake and black scorpionfish, the mesh size larger than 26 mm would be more appropriate.

Does environmental DNA reflect the actual phytoplankton diversity in the aquatic environment? Case study of marine mucilage in the Sea of Marmara.

The present study was designed to assess the effectiveness of the eDNA metabarcoding approach to determine the phytoplankton composition in the marine environment with a special focus on mucilage episodes in the Sea of Marmara. For this purpose, the samples were collected from 5 different sites located in the Sea of Marmara and the northern Aegean Sea during the mucilage episode in June 2021. The phytoplankton diversity was analyzed morphologically and by 18S rRNA gene amplicon sequencing, and the dataset of both methods was compared, accordingly. The results showed significant differences between methods in terms of composition and the abundance of the phytoplankton groups. While Miozoa was the most abundant group by metabarcoding, light microscopy (LM) indicated a dominance of Bacillariophyta. Katablepharidophyta was found at lower abundances by the metabarcoding (representing < 1% of the community); the members of this phylum were not observed by a microscope. At the lower taxonomic levels, Chaetoceros was the only genus detected in all samples by both methods. Additionally, while mucilage-forming Gonyaulax fragilis, Cylindrotheca closterium, and Thalassiosira rotula were detected to species-level by LM, metabarcoding was able to determine these organisms at the genus level. On the other hand, the genus Arcocellulus was found in all metabarcoding datasets and not detected by microscopy. The results indicated that metabarcoding can detect a greater number of genera and reveal taxa that were overlooked by light microscopy but to develop a complete picture of phytoplankton diversity in the sample, microscopical observations still are in need.

Spatiotemporal long-term wind and storm characteristics over the eastern Mediterranean Sea

The main objective of the present study is to provide a comprehensive analysis of wind characteristics over the eastern Mediterranean Sea using three widely used wind fields, namely ECMWF ERA-Interim, ECMWF ERA5, and NCEP/CFSR. Wind speeds from three reanalysis datasets were validated with measurements at three different locations (Antalya, Dardanelles, and Silifke). The results of several statistical investigations show that ERA5 and CFSR wind data provide reasonably better fits with measurements compared to results of ERA-Interim data, especially in higher percentiles. Long-term wind and storm characteristics, long-term variability, and long-term trends with statistical significance levels were evaluated covering the period of 1979–2018. Long-term strong wind conditions with no significant long-term trend were detected in the northern Aegean Sea, while relatively weak, short-lived, and highly variable winds were determined in the southern, northern, and eastern Levantine Basin. For five selected regions, local analyses such as storm duration, and 99th percentile wind speed were evaluated in detail. Extreme wind analyses indicate that the largest discrepancy between the results of ERA5 and CFSR wind datasets was observed in the eastern Levantine basin, with the RC (relative difference) exceeding 22%. The highest extreme wind speeds for the 100-year return period were found in the northern Aegean Sea with values exceeding 21 m/s and 25 m/s for ERA5 and CFSR, respectively.

Age, Growth and Reproduction of the Thornback ray, Raja clavata (Linnaeus, 1758) in the Waters Off Gökçeada (the Northern Aegean Sea)

Age, Growth and Reproduction of the Thornback ray, Raja clavata (Linnaeus, 1758) in the Waters Off Gökçeada (the Northern Aegean Sea)

Microbiome Profile of the Mediterranean Mussel (Mytilus galloprovincialis) from Northern Aegean Sea (Greece) Culture Areas, Based on a 16S rRNA Next Generation Sequencing Approach

Mediterranean mussels (Mytilus galloprovincialis), due to their nutritional mechanisms which involve filtering huge amounts of water, are affected by seawater pollution and can host microbial diversity of environmental origin, as well as pathogenic bacteria that must be constantly monitored. Herein, we applied a Next Generation Sequencing (NGS) metabarcoding approach in order to study the M. galloprovincialis microbiota. Collection of samples was conducted during winter and summer months from various mussel farm zones located in specific farm regions in the Thermaikos gulf, the northern Aegean Sea, Greece. A microbiological test was performed for the enumeration of Escherichia coli and the presence of Salmonella sp. DNA extraction and amplification of the whole bacterial 16S rRNA gene, followed by NGS amplicon sequencing and taxonomic classification, were carried out. Statistically significant differences (p &lt; 0.05) in the abundance of the most dominant bacterial phyla, families and genera between winter and summer time periods, regions, as well as zones within each region of sampling, were evaluated with z-score computation. According to the obtained results, the most prevalent taxa at the genus level were Mycoplasma (12.2%), Anaplasma (5.8%), Ruegeria (5.2%) and Mariniblastus (2.1%). Significant differences in the abundance of the most dominant genera were found at all levels of comparison (seasons, regions and zones within each region), highlighting the dynamic character of microorganisms, which might be affected by microenvironmental, temporal and spatial changes. The present research contributes to the characterization of M. galloprovincialis microbiome in areas that have not been studied previously, setting the baseline for future, more thorough investigations of the specific bivalve species and its bacterial profile in the above geographic regions.

Prey selection patterns of bottlenose dolphins depredating bottom-set gillnets in the northern Aegean Sea

Understanding the foraging strategies of marine megafauna that interact with fisheries is key to conflict mitigation. Bottlenose dolphins Tursiops truncatus in the northern Aegean Sea frequently depredate bottom-set nets, but whether they exhibit prey selection within depredation events remains unknown. We conducted 80 fishing trials over 2 seasons (2020 and 2021) using gillnets in the Thermaikos Gulf, and investigated patterns in the catch and gear damage to determine whether bottlenose dolphins target certain genera over others. A high preference index was calculated for demersal fish like Mullus and Trachurus, as well as less frequently occurring pelagic fishes like Sphyraena. We also found a strong indication that dolphins target certain sizes of fish in certain genera, namely the shorter specimens of larger fishes and the larger specimens of shorter fishes. In conjunction with the patterns in the vertical position of holes torn in the nets, our findings suggest that bottlenose dolphins take advantage of whichever fish are seasonally prevalent.

Temporal Variations in Hematological, Immunological and Serum Biochemical Parameters of Rainbow Trout (Oncorhynchus mykiss) Acclimated to High-Saline Water in the Northern Aegean Sea

Abstract The present study evaluated the health status of rainbow trout (30.24±5.34 g) acclimated to high-saline water (28‰). Among adaptation procedures, gradually-acclimated (for 48 h) fish showed best performance, which were then introduced to the offshore cage-farm for further monitoring of fish health in marine environment over a long-term period of 100 days, until harvest weight of 319.9±48.51 g. Fish health and welfare was evaluated by means of biochemical parameters (viscerasomatic index, hepatosomatic index, mesenteric fat index, and spleen somatic index), hematological parameters (serum glucose, triglyceride, cholesterol, total protein, albumin, globulin), and immune parameters (lysozyme, myeloperoxidase, respiratory burst and potential killing values). Gradual acclimation to high-saline water did not show any adverse effects on health parameters. No significant differences were found in biometric measures (P&gt;0.05). However, a time-dependent increase was recorded in hematology markers (P&lt;0.05) after seawater transfer, and the health status improved over long term from March 7 to June 14, 2018. All serum biochemical markers, except the total protein showed significant alterations (P&lt;0.05) in long term but without detrimental influence by day 100. Therefore, it seems possible to expand trout farms from brackish water sites to higher saline environments up to 28‰ salinity, with no detrimental impacts on fish health, that in turn may significantly contribute to the extension of potential aquaculture sites to wider areas.

Gelibolu Yarımadası’ndan (Kuzey Ege Denizi, Türkiye) Avlanan Palamut (Sarda sarda Bloch, 1793), Uskumru (Scomber scombrus Linnaeus, 1758) ve Kolyoz (Scomber colias Gmelin, 1789) Balıklarının Toplam Boy, Toplam Ağırlık, Maksimum Vücut Çevresi ve Operkulum Çevresi Arasındaki İlişkiler

Bu çalışma Gelibolu Yarımadası açıklarında (Kuzey Ege Denizi, Türkiye) Ocak 2017-Aralık 2017 tarihleri arasında palamut (Sarda sarda Bloch, 1793), uskumru (Scomber scombrus Linnaeus, 1758) ve kolyoz (Scomber colias Gmelin, 1789) türlerinin boy-ağırlık ve boy-çevre ilişkilerini ortaya çıkarmak için ticari balıkçılar tarafından avlanan öü balıkları kullanmak suretiyle gerçekleştirilmiştir. Boy-ağırlık ilişkisi palamut, uskumru ve kolyoz balıkları için, sırasıyla, W=0.0143TL2.84 (R2=0.89), W=0.0059TL3.11 (R2=0.92) ve W=0.0059TL3.11 (R2=0.92) olarak tahmin edildi. Yine sırasıyla bu türlerin boy-operkulum çevre ilişkileri Gope=0.3988TL+0.2512 (R2=0.78), Gope=0.3528TL+0.8122 (R2=0.84) ve Gope=0.4295TL-0.5991 (R2=0.94) olarak hesaplanırken boy-maksimum vücut çevre ilişkileri ise Gmak=0.5993TL-4.1237 (R2=0.79), Gmak=0.4206TL+0.2732 (R2=0.83) ve Gmak=0.4676TL-0.168 olarak saptanmıştır. Bu çalışma Karadeniz’i de kapsayacak şekilde tüm Akdeniz Havzası için bu türlerin boy-operkulum ve boy-maksimum vücut çevresi ile ilgili ilk bilgileri içermektedir.