Turkish Marine Waters Research Articles

Genetic Confirmation of the Striped Eel Catfish Plotosus lineatus (Thunberg, 1787) from Iskenderun Bay (Eastern Mediterranean, Türkiye)

The records of the striper eel catfish Plotosus lineatus have been assigned based on morphological characters in the Mediterranean Sea. However, molecular and genetic analyses are needed to confirm the morphological taxonomic determination and avoid misidentification. In this study, the mitochondrial cytochrome c oxidase subunit I (COI) gene region was used for genetic confirmation of Plotosus lineatus in the Mediterranean Sea. The obtained P. lineatus sequences were found to have a 100% identity match with the Red Sea and Mediterranean records. The present molecular genetic study confirms the presence of P. lineatus in Turkish marine waters. Also, this study is the first genetic confirmation of P. lineatus on the coast of Türkiye and in the Mediterranean Sea.

Capture of a new-born shortfin mako shark Isurus oxyrinchus (Lamniformes: Lamnidae), with updated records from the Turkish marine waters

The study reports on the capture of a new-born specimen of shortfin mako shark Isurus oxyrinchus Rafinesque, 1810 off Karantina islet coast, Urla, Izmir (north Aegean Sea). This specimen measured 761 mm in total length and weighed 2900 g. The historical and recent captures of the species in the area shows the presence of new-born, juvenile and adult males and females. The distribution of these specimens suggests the potential occurrence of a nursery ground in the same area. To preserve the extirpation of the species throughout the area where it finds favourable environmental parameters to live, a management plan should be conducted to ensure the establishment of a viable population in the Turkish marine waters

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.

First record of Sebastes schlegelii Hilgendorf, 1880 along the Turkish Black Sea coast – new addition to the alien species inventory

Sebastes schlegelii is a typical bottom dwelling boreal species, whose native distribution range includes Japan, Korean peninsula and China. This northwest Pacific originated species has recently been recorded from the Crimean and Caucasian coast (northern Black Sea), whose introduction was assumed to be either by balast waters or the acclimatization of Crassostrea gigas (Pacific oyster). On 16 August 2023, a single S. schlegelii specimen with 20.6 cm standard length and 282.1 g in weight was captured off Ünye, Ordu coast (southeastern Black Sea), which was previously an unreported fish from the Turkish marine waters. Detailed morphometric and meristic characteristics are presented in the paper, and species identification was further confirmed by genetic analysis. Available information reveals this alien species to be fished regularly, although in small quantities, indicating a presumably established population in the region. The species should be treated as a potentially invasive fish, since it may negatively influence to the local biodiversity through interspecific competition. Close monitoring of its existing population is strongly suggested.

Capture of a Rare Smoothback Angelshark Squatina oculata (Squatinidae) in Turkish 2 Waters, with Updated Records from the eastern Mediterranean Sea

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

First Record of the Little Gulper Shark, Centrophorus uyato (Rafinesque, 1810), in the Turkish Marine Waters of the North Aegean Sea

First Record of the Little Gulper Shark, Centrophorus uyato (Rafinesque, 1810), in the Turkish Marine Waters of the North Aegean Sea

Ecological quality status of the Turkish coastal waters by using a marine macrophytic biotic index (EEI-c)

The present study includes the results of the second benthic macrophytes? monitoring period of a survey of ecological status from the Turkish coasts. The biotic index Ecological Evaluation Index (EEI-c) was used to assess the ecological status classes (ESC) and MA-LUSI the anthropogenic pressures. Sampling was made by the quadrat (20 × 20 cm) method, and the samples were collected from 93 sites in Turkish coastal waters between 2017 and 2019. In total, 240 taxa were found in the Turkish marine waters. Forty sites were classified into High ESC, 24 sites into Good, 12 sites into Moderate, 13 sites into Poor, and 4 sites into Bad ESC. The relationship between the pressure index MA-LUSI and EEIeqr values was also tested, and a negative correlation (R²= 0.62) was found.

Extension of the Striped Eel Catfish Plotosus lineatus (Thunberg, 1787) from the eastern Mediterranean Coast to the Mersin Bay on the western Mediterranean Coast of Turkey

A group of schools of striped eel catfish Plotosus lineatus (Thunberg, 1787) was photographed during scuba diving at depths of 10 m and 17 m on 11 July 2022 and on 24 September 2022 from Kızkalesi and Boğsak regions in the Mersin Bay of the Mediterranean coast of Turkey. With the present study, P. lineatus is extending its distribution to the western Mediterranean coastal waters after its first occurrence in 2016 in the İskenderun Bay of Turkish Marine waters.

A Review on the Potential Usage of Lionfishes (Pterois spp.) in Biomedical and Bioinspired Applications

Lionfishes are recognized as invasive and predatory species in the world. The genus Pterois belongs to the Scorpaenidae family has 10 confirmed species. Among them, two species Pterois miles and P. volitans were reported as non-indigenous species in Turkish marine waters. Although dorsal, pelvic, and anal fins of lionfish have venom-releasing spines which can have systemic effects such as severe pain, fever, vomiting, and dizziness, there are no reports of death by lionfish in the literature anyway. After careful removal of the venomous spines, lionfish meat is suitable for human consumption. The bioactivity of homogenates obtained from the venomous spines of lionfish has been the subject of various research since the 1950s. Until now, it has been proven that the venomous spines of the lionfish contain anticancer, antiviral, anti-inflammatory, anticoagulant, antioxidant, and antibacterial compounds and can be used in biomedical applications as a natural resource of marine origin. Moreover, the spine shape of lionfish has provided inspiration that can be useful in designing reusable syringe needles and sterilizable plungers, thereby reducing biomedical waste and sharps disposal costs. Additionally, the fins and spines of lionfish, which are typically removed and discarded, are used to make jewellery. This review, therefore, focused on evaluating alternative management actions to bring these invasive fish into the economy and control their populations, owing to both their use in biomedical fields and their suitability for bioinspiration.

Preliminary Assessment of Invasive Lionfish Pterois miles Using Underwater Visual Census Method in the Northeastern Mediterranean

Abstract Underwater visual census (UVC) is a commonly used approach for assessing fish density and biomass. Iskenderun Bay, comprising the Samandağ coast in Turkey, is the most important introduction pathway of alien species in the northeastern Mediterranean. In this study, the density, abundance, distribution and interaction of invasive lionfish or devil firefish Pterois miles were assessed using the UVC method on the Samandağ coast. The total transect area monitored on the Samandağ coast was 4.500 m2. Species richness, Shannon’s diversity index and rate of biomass were 25, 1.81 and 73.5 m2, respectively. Reduced diversity was observed with increasing depths. The sandy seafloor was a limiting factor for lionfish distribution. There was a significant positive correlation between lionfish total density and both the Shannon diversity index (r = 0.99, P<0.001) and Shannon evenness index (r = 0.99, P<0.05). A high number of significant positive correlations (P<0.05) were detected between the occurrence of lionfish and the occurrence of both the native species and other alien species. The first stock assessment study of lionfish by the UVC method in Turkish marine waters revealed that native species are under very high pressure from lionfish species, especially Chromis, Sparids and Wrasses, indicating negative effects of lionfish on regional native biodiversity.

Genetic Analysis of the Mitochondrial rrnS Gene of Zoonotic Anisakis pegreffii (Nematoda: Anisakidae) Isolated from Micromesistius Poutassou (R.) in the Aegean Sea

Ascaridoid nematodes were found in viscera of the blue whiting Micromesistius poutassou (Risso, 1826) from the Aegean Sea in the parasitological examination. Collected nematodes were morphologically identified as the third (L3) stage of Anisakis type I larvae and then subject to Restriction Fragment Length Polymorphism (RFLP) analysis of the internal transcribed spacer (ITS) region to identify the species. Randomly selected larvae were molecularly confirmed as Anisakis pegreffii by RFLP analysis. Subsequently, L3 of A. pegreffii were amplified and bi-directionally sequenced at the small subunit ribosomal RNA (rrnS) gene. The rrnS sequence of A. pegreffii (MT484284) had 100% identity with the rrnS gene of A. pegreffii (JX500050, LC222461, MF140359, MT312511, MT312512) which were found in fish and cetaceans hosts, Scomber japonicus, Conger myriaster, Neophocaena asiaeorientalis, and Stenella coeruleoalba, from the Mediterranean Sea, Japanese, Chinese, and Korean waters. This study provided the genetic analysis of zoonotic A. pegreffii from the Turkish marine waters based on the rrnS gene for the first time. This sequence (MT484284) can be used as the novel rrnS sequence of A. pegreffii in the genetic analysis for ascaridoid nematodes in the Mediterranean Sea.

Occurrence of the Blue Button Porpita porpita (Linnaeus, 1758) in the Iskenderun Bay, Northeastern Mediterranean Coast of Turkey

The blue button Porpita porpita (Linnaeus, 1758) was observed for the first time in July 2018 in the Iskenderun Bay, Northeastern Mediterranean coast of Turkey. This is the third record of this species for Turkish marine waters, while it is the first record for Iskenderun bay. The presence of P. porpita in the northeastern Mediterranean coast of Turkey shows its extension from northwestern Mediterranean coast (Antalya Bay) of Turkey.

Occurrence of microplastics in the gastrointestinal tracts of some edible fish species along the Turkish coast

Plastics have become an inseparable part of modern life as a consequence of their versatility, low cost, durability, and lightweight. In this study, the presence of microplastics (MPs) in the stomachs and digestive tracts of 243 individuals of leaping mullet (Chelon saliens (Risso, 1810)), red mullet (Mullus barbatus barbatus Linnaeus, 1758), surmullet (Mullus surmuletus Linnaeus, 1758), Mediterranean horse mackerel (Trachurus mediterraneus (Steindachner, 1868)), and sand steenbras (Lithognathus mormyrus (Linnaeus, 1758)), collected along the Marmara, Aegean, and Mediterranean coasts of Turkey was examined microscopically and through μ-Raman analysis. A total of 283 MP particles were extracted. Among the examined species, the average MP concentration was 1.1 MP per fish (MPs fish$^{-1}$). The number of MPs detected was 2.5 MPs fish$^{-1}$ for leaping mullet, 1.1 MPs fish$^{-1}$ for red mullet, 0.6 MPs fish$^{-1}$ for sand steenbras, and 0.4 MPs fish$^{-1}$ for Mediterranean horse mackerel and surmullet. The size of the MPs ranged from 0.028 to 4.909 mm. To determine the polymer types of the MPs, a μ-Raman analysis was conducted. The most frequently detected polymers were polypropylene (26%), polyethylene (21.9%), polyethylene terephthalate/polyester (8.2%), and cellulose (7.5%). The results of this study showed that MP pollution represents an emerging threat to the fish of Turkish marine waters.

First molecular data on the validity of Myxobolus ichkeulensis (Cnidaria: Myxosporea) from Mugil cephalus (Mugilidae) in Turkish waters

To date, there is no report on molecular characterisation of Myxobolus ichkeulensis in Mugil cephalus (Mugilidae) in Turkish marine waters. The aim of the current research was to provide the first molecular data on M. ichkeulensis from M. cephalus in Turkish Black Sea coasts. A total of 40 M. cephalus specimens were examined for the presence of M. ichkeulensis in the Turkish Black Sea coasts during January 2017 and April 2017. In the present study, M. ichkeulensis was identified based upon the myxospore morphology, host and tissue specificity, and SSU rRNA sequence. Phylogenetic analysis using neighbor-joining also revealed that our isolate (#GZP-2018-Samsun1) was clustered with other Myxobolus species that infect M. cephalus. The current study includes the morphological and histopathological descriptions and first molecular data on M. ichkeulensis in M. cephalus in Turkish marine waters. M. ichkeulensis was also reported from the M. cephalus in the coast of the Black Sea in Turkey for the first time. Moreover, our current genetic data was recorded as the new valid SSU rRNA sequence (MH374629) for M. ichkeulensis in the GenBank database.

Ecological quality status of the Turkish coastal waters by using marine macrophytes (macroalgae and angiosperms)

Marine macrophytes (macroalgae and angiosperms) were defined as one of the biological quality elements to assess the ecological quality status of transitional and coastal waters by the European Water Framework Directive (WFD, 2000/60/EC). In the present study, the Ecological Evaluation Index (EEI-c) was tested to assess the anthropogenic impact by using marine benthic macrophytes (macroalgae and angiosperms) and pressures by using MA-LUSI in the Turkish marine waters. Macrophyte samples were collected from 56 stations on the coasts of Turkey (at 17 Black Sea, 15 Marmara Sea, 13 Aegean Sea and 11 Mediterranean coastal water bodies) in the summer period between 2014 and 2016. In total, 209 marine macrophytes (macroalgae and angiosperms) taxa were found in all stations. The study revealed high ecological status class for 15 sites, good for 21 sites, moderate for 6 sites, poor for 10 sites, and bad for 4 sites. The MA-LUSI index was tested from the Corine land cover map which affects 1.5 km buffer zone around the sampling sites. The relationship between the pressure index MA-LUSI and EEI-ceqr (eqr: ecological quality ratio) was also tested, and a negative linear relationship was found between MA-LUSI and EEI-ceqr in the Turkish sites. The present study supports the use of the EEI-c index for ecological quality state classification in a wide area of Turkish coastal waters.

Is Peniculus Fistula Fistula Nordmann, 1832 Reported On Coryphaena hippurus Linnaeus, 1758 From Turkey? Updated Data with Further Comments And Considerations

Abstract 53 striped surmullet, Mullus surmuletus Linnaeus, 1758 (Teleostei, Mullidae), were collected from the Marmara Sea, Turkey and examined for metazoan parasites in July 2017. The parasitic copepod, Peniculus fistula fistula Nordmann, 1832 (Pennellidae), was collected from all the hosts, both on fins and body surface. This is the second report of this copepod in Turkish marine waters. Although Peniculus fistula fistula was reported for the first time on Coryphaena hippurus Linnaeus, 1758 by Öktener (2008), there was an indefiniteness and doubt about the occurrence of this parasite. This study aimed to confirm occurrence of Peniculus fistula fistula in Turkey and to present revised host list with comments.

First Record of Pomacanthus imperator (Bloch, 1787) from Turkish Marine Waters

A single specimen of Pomacanthus imperator (312 mm in total length and 1020 g in weight) was
 caught by a spear at a depth of 10 m on 28 April 2019 from Iskenderun Bay (Konacık, Arsuz coast),
 Turkey. All measurements, counts, morphological description and colors of P. imperator specimen
 caught agree with the previous descriptions for this species. In this paper, the occurence of P.
 imperator is reported for the first time from Iskenderun Bay in Turkish Marine waters. This species
 is probably a Red Sea immigrant entered into the Mediterranean Sea through Suez Canal. 

A Checklist of the Non-indigenous Fishes in Turkish Marine Waters

A checklist of non-indigenous marine fishes including bony, cartilaginous and jawless distributed along the Turkish Marine Waters was for the first time generated in the present study. The number of records of non-indigenous fish species found in Turkish marine waters were 101 of which 89 bony, 11 cartilaginous and 1 jawless. In terms of occurrence of non-indigenous fish species in the surrounding Turkish marine waters, the Mediterranean coast has the highest diversity (92 species), followed by the Aegean Sea (50 species), the Marmara Sea (11 species) and the Black Sea (2 species). The Indo-Pacific origin of the non-indigenous fish species is represented with 73 species while the Atlantic origin of the non-indigenous species is represented with 22 species. Only first occurrence of a species in the Mediterranean, Aegean, Marmara and Black Sea Coasts of Turkey is given with its literature in the list.

Assessing DNA Barcodes for Identification of Pufferfish Species (Tetraodontidae) in Turkish Marine Waters

In Turkish marine waters, pufferfish belongs to Tetraondontidae family are represented with 8 species, Lagocephalus lagocephalus, L. sceleratus, L. spadiceus, L. suezensis, L. guentheri, Sphoeroides pachygaster, Torquigener flavimaculosus and Tylerius spinosissimus. DNA barcoding can be useful in the assessment of cryptic or morphologically similar species of identification which is widespread in marine environment. DNA barcode identification of the eight puffer species of the Tetraodontidae family in Turkish marine waters were examined by using mtDNA sequencing of the amplified partial mitochondrial cytochrome c oxidase I (COI) gene. COI contained 189 variable and 337 conservative nucleotides of which 183 were parsimony informative over 526 bp. Mean genetic diversity all species was found 0.18164. The highest and lowest nucleotide divergence was observed L.spadiceus (0.0022) and between L. sceleratus, L. suezensis, L. lagocephalus, L. guentheri and S. pachygaster (0.0000) respectively. The number of detected different haplotypes were 10 out of 23 sequences, and haplotype diversity was found to be 1.000. 

First Record of Caligus zei (Copepoda: Caligidae) on John Dory, Zeus faber in Turkish Marine Waters

The parasitic copepod, Caligus zei Norman and Scott T., 1906 was found on the John dory (Zeus faber Linnaeus, 1758) during a demersal fish stock assessment in the Sea of Marmara during April 2017. This is the first report of this copepod in Turkish marine waters. Descriptions of the male and female Caligus zei, including details of appendage structure of recovered specimens, are provided.