Turkish Seas Research Articles

Efficiency of different collectors for spat settlement of Mediterranean mussel (Mytilus galloprovincialis) in the southeastern Marmara Sea, Türkiye

ABSTRACT Mediterranean mussel have spread almost throughout Turkish seas. The objective of this study was to set up longline systems to determine spat efficiency by two different systems (buoy and pipe) consisting of three different materials, new rope, used rope and used net, in Erdek Bay. The second objective was to identify whether waste materials could be used in mussel culture. Sea water temperature, salinity, dissolved oxygen, chlorophyll-a, total suspended, inorganic and organic matter were measured at monthly intervals. Results revealed that the highest settlement (4196 spat) was observed in the collectors made of used nets in the pipe system (October 2016). In contrast, the lowest value (2 spat) was recorded from the collectors made of new ropes in the buoy system (August 2016). Waste materials presented relatively better results on settlement than the new ropes. The optimum production was observed in the mussel farm with 1239 spat in the buoy and 1607 spat in the pipe systems, which were commissioned in April 2016. It is concluded that the spat performance was affected by collectors and materials. Therefore, we propose the use of used ropes and used nets, which will allow more effective attachment surfaces to achieve higher spacing settlement.

Where Have You Been Hiding? Re-Emergence of Squatina oculata in the Sea of Marmara, with a Review of Captures in Turkish Seas

Where Have You Been Hiding? Re-Emergence of Squatina oculata in the Sea of Marmara, with a Review of Captures in Turkish Seas

Oil Spill Modeling of the M/T Sti Pimlico and M/V Celestyal Crystal Accident on Çanakkale Strait

Turkish Sea Area is the most important waterway because of its geographical position. According to 2022 statistics of strait passage, 9904 tanker vessels passed through the Strait of Çanakkale. This statistical value shows that the Strait of Çanakkale is at risk due to the tanker vessels’ passage. On June 27, 2015, the Celestyal Crystal cruise ship and the STI Pimlico tanker ship collided in the Çanakkale Traffic Separation Scheme, approximately 0.7 nautical miles from the Gelibolu Lighthouse. STI Pimlico suffered an explosion in one of the port wing cargo tanks and listed 15° to port. There were no injuries in the incident, but it was reported that naphtha leaked from the ship into the sea. Directorate General of Coastal Safety teams responded to oil spillage immediately, the leak was taken under control before it spread too much. In this study, the pollution and spread that will occur in case the response of coastal safety teams is delayed has been estimated. The oil spill was determined according to time and place, taking into account the northerly wind direction and strength. Leak simulation was performed with the GNOMETM simulation program. Characteristic of cargo on STI Pimlico was taken from the ADIOS2 program. Results of the simulation showed that the spill reached the coast. 7 kilometers of the coast was polluted by an oil spill.

Establishing a fish repository at Ege University Faculty of Fisheries (1965-2023): A Journey on a long and challenging road to becoming a museum

This study examined preserved marine fish specimens collected from numerous field surveys conducted along Türkiye’s Black Sea, Marmara, Aegean, and Mediterranean coasts since 1965. Our review and categorization of these materials revealed that the specimens belong to 360 species from 131 families. Current data shows that the museum collection includes 20 species of cartilaginous fish and 8 species of bony fish listed as endangered on the IUCN Red List, alongside 54 non-native fish species. Prepared according to museum standards by Ege University Fisheries Faculty’s Scientific Material (ESFM), this collection of Turkish marine fish constitutes 66% of all Turkish marine fish fauna. This makes it the largest and oldest marine fish collection in Türkiye. Considering Türkiye’s maritime borders with neighboring countries, this collection is significant nationally and globally. Given the diverse marine fish species in Turkish seas over the past half-century, this preserved material is a vital reference for local and foreign ichthyologists. If organized and transformed into a visitable museum, this extensive collection could raise awareness about the diversity of marine fish species in our seas. As a result, we have established the ” biological repository of Turkish Marine Fish Department” in the Faculty Museum, now known as the Fisheries Faculty’s Scientific Material (ESFM) at Ege University. We present the fish in the collection as a species list.

Review of marine alien isopods in Türkiye with two new records: of Paracerceis sculpta and Paranthura japonica

This study focuses on the alien isopod species recorded in the Turkish seas. To date, two alien species (Paradella dianae, Sphaeroma walkeri) have been reported in the country, accounting for almost 2.4% of the total number of isopod species occurring in the Turkish seas. The faunistic analysis of benthic samples collected from Dardanelles (Çanakkale) Straits and Izmir Bay revealed two new alien isopod species (Paranthura japonica and Paracerceis sculpta), on the Turkish coasts. Additionally, this is the first record of P. japonica in the Black Sea ecosystem. This study analyses and discusses the morphological, ecological and distributional characteristics of the species.

Historical and Contemporary Occurrence of Odontaspis ferox (Risso, 1810) (Lamniformes: Odontaspididae) in Turkish Seas, with New Records from the Region

Historical and Contemporary Occurrence of Odontaspis ferox (Risso, 1810) (Lamniformes: Odontaspididae) in Turkish Seas, with New Records from the Region

15. ve 16. YÜZYILLARDA AKDENİZ’DE OSMANLI DENİZ(CİLİK) GÜCÜNÜN OLUŞUMUNDAKİ ETKENLER

The needs that changed and diversified with the political, technological and scientific developments in the 21st century have brought about new risks and threats. New dimensions of security have started to be discussed against newly emerging risks and threats in international relations. Among the new security issues, the sea comes to the fore both as an area of expansion of states and as an area that gains importance in terms of military, energy, economic and ecological (environmental) security aspects. At this point, maritime policies, which have become a geostrategic need for states in regions that have become areas of power struggle due to their geopolitical positions, tend to change and develop too. Today, the Mediterranean is one of the regions where these power struggles take place just like in history. The necessities and basic factors that paved the way for the 15th and 16th century Turkish (Ottoman) domination in the Mediterranean basin, which is the cradle of Turkish seafaring, were evaluated within the framework of sea power theories and the decision-making model put forward within the scope of the study in terms of shedding light on the present day.
 Objective: In this study, an evaluation from a historical perspective was made based on the analysis model of the maritimization policy, which was formed within the framework of philosophical, cultural and theoretical foundations in the Mediterranean. With this evaluation, the building blocks in the formation of the Turkish maritime policy were tried to be shown.
 Methodology: In this study, a qualitative research method was used and a literature review was conducted on the subject. In the light of the historical and theoretical information that was obtained, an analysis of the period, which is the subject of the study, was tried to be made.
 Findings: The necessities and opportunities arising from the external conjuncture in the formation of the Turkish (Ottoman) maritime policy in the 15th and 16th centuries were determined with this study, and accordingly, the abilities of the decision-makers to benefit from these opportunities were shown. In addition, the events that formed the basis of the Turkish (Ottoman) maritime domination and sea power in the period in question were handled from a different perspective; and in this context, the emergence of the Turkish pirates, who constituted the source of the Turkish sea power of the period, and the Christianization policies that Spain applied to the Muslim and Jewish peoples in the Iberian Peninsula were associated.
 Originality: Within the scope of the study, a new decision-making model has been developed for the formulation of maritimization policies. In addition, the effect of the deportation policy implemented by Spain in the relevant period on the formation of the Turkish sea power was revealed for the first time.

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.

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.

Türkiye’nin Doğu Akdeniz Kıyılarında Yayılım Gösteren İki Diplodus Tür Populasyonunda DNA Barkodlama ve Filogenetik analiz

Since Turkey is surrounded by seas on three sides and has different climatic characteristics, it has an extremely rich biodiversity. Identifying fish species and varieties is of great importance for protecting them from drought conditions seen in recent years and using them as a source of human food protein. The purpose of this study was to identify the genetic diversity of Diplodus, one of the fish species the importance of which is under appreciated, in Turkish seas. To this end, the polymorphism between the populations of two species (Diplodus vulgaris and Diplodus sargus) from the Sparidae (Coral fish) family was determined using the nucleotide sequence of the mitochondrial cytochrome c oxidase I (COI) gene, which is 652 base pairs long. 143 specimens of Diplodus were collected from the locations in the Eastern Mediterranean (İskenderun and Mersin) and Western Mediterranean (Antalya). The COI gene was amplified by PCR, genetic diversity analyses of these loci were carried out, and a phylogenetic tree was created to show the relationships between the isolates with a high difference. In conclusion, based on the haplotype and nucleotide diversity patterns, it was found that the COI gene had a low genetic variation among the populations.

Occurrence of Aulopus filamentosus (Bloch, 1792) (Aulopidae) in the Turkish Aegean Sea (Sığacık Bay, E. Mediterranean)

Three specimens of A. filamentosus were captured by recreational anglers off Sığacık Bay, Izmir, at a depth of 220 m on 22 March 2023. The total length of these specimens was between 255 and 310 mm. Thus, the certain record number has reached at least twenty specimens in the Turkish seas. This paper presents the fifth confirmed record of A. filamentosus from the southeastern Aegean Sea. Though the sporadic occurrences of this species in the Aegean Sea do not indicate an established population for the time being, it signs that it is becoming abundant.

New Records for Microalgae Species of the Turkish Seas Under the Effect of Intense Mucilage in the Sea of Marmara

Objective: New records of microalgae species for Turkish seas taking into account the species lists published to date have been reported in this study conducted in the Sea of Marmara and the Aegean Sea. Furthermore, new records of microalgae species for the Sea of Marmara and the Aegean Sea were listed. Materials and Methods: New record species for Turkish seas were described by their morphological and ecological features and also their images were taken under a light microscope with epifluorescence attachment, and also some of them were photographed on a scanning electron microscope. Results: A total of 66 new record species were identified in this study. A total of 25 microalgae taxa belonging to 11 taxonomic classes were recorded for the first time for Turkish seas. Two taxa were freshwater or brackish water form, which is known from the lakes. The class Prymnesiophyceae had seven taxa that were recorded for the first time, followed by Bacillariophyceae and Dinophyceae with four taxa and the other classes. Furthermore, a total of 65 taxa belonging to 16 taxonomic classes were recorded for the first time for the Sea of Marmara. Twelve taxa were freshwater or brackish water form, which is known from the lakes. Among these, Dinophyceae had 24 taxa, followed by Prymnesiophyceae with 11 taxa, and Bacillariophyceae with 9 taxa and the other classes. In addition, one new record taxon was detected for the Aegean Sea. Conclusion: New records of microalgae detected in the Sea of Marmara during this study period will provide an important contribution to both the microalgae checklist of Turkish seas, the Sea of Marmara and the Aegean Sea.

Assessing the impact of the Covid-19 pandemic on the financial and economic structure performance of Turkish sea freight transport sector

The impact of Covid-19 on the global economy’s functioning and the long-term growth of supply chains was first reported in Türkiye in March 2020. The purpose of this study is to determine whether the Covid-19 pandemic has had an impact on the financial and economic structure performance of Turkish sea freight transport sector, as well as how the sector has adapted to the new reality brought on by Covid-19. In this regard, the consolidated financial statements of 997 companies for the year 2020 were studied using ratio analysis, and the results were compared to the financial outputs of the 2008 global financial crisis and the European sovereign dept crisis. As a result of the study, it was determined that the sector’s response to crises in different time periods varied. In order to avoid debt default during the pandemic, the capital structure restricted short-term resources while increasing long-term resources. Despite the pandemic conditions, it has been noticed that there are no barriers to accessing money market instruments in the sector, that the working capital structure has been enhanced, and that a balanced financing plan has been established to ensure the continuity of cash flows. This is the first study that analyses the sector as a whole, reveals the financial and economic repercussions of the pandemic on the sector, and compares these effects to those of recent financial crises. In addition, authorities of the maritime transport industry in other countries will find this helpful research for conducting comparative analyses, and the findings can be generalised.

Prediction of daily sea water temperature in Turkish seas using machine learning approaches

Prediction of daily sea water temperature in Turkish seas using machine learning approaches

Climate Change's Impact on Turkish Seas’ Temperature and Aquaculture

Climate is one of the most important elements that play a role in shaping the habitats, lifestyles and physical characteristics of all living things in the Biosphere. Sea creatures are a part of the biosphere. Climate change is an important threat not only to our entire planet but also to oceans, seas and sea creatures. Turkey is surrounded by seas with different ecology and climate, namely the Mediterranean, Aegean, Marmara and Black Seas. Aquaculture and fishing are important sources of income in Turkey's seas and freshwaters. In addition, transportation, tourism, sports, etc. activities are socio-economic activities carried out in its seas and waters. The increase in temperature in the seas of Turkey, especially in the Mediterranean, transforms the seas into tropical seas and invader species migrate to the region from tropical seas. In this study, the temperature increase in Turkish seas will be tried to be revealed. In the light of this change, possible changes in Turkish seas and the effects of climate change on seas and fishery products will be discussed. The data obtained from the measurements of the marine meteorology observation systems of the Turkish State Meteorological Service between the years 1970-2021 were analyzed for the Mediterranean, Aegean Sea, Marmara and Black Sea. Sea surface temperatures (SST) in the seas surrounding Turkey have increased by about 0.4 - 1.4 °C in the last two decades, and it has been determined that the maximum increases are between about 2.3 - 3.5 °C in this period. The highest increase in SSTs was detected in the Black Sea. İklim, Biyosferdeki (Canlı-kürenin) tüm canlıların yaşam alanlarını, yaşam şekillerini ve canlıların fiziksel özelliklerinin şekillenmesinde rol oynayan en önemli unsurdan bir tanesidir. Canlı-kürenin bir parçasını da deniz canlıları oluşturmaktadır. İklim değişikliği, tüm gezegenimiz için olduğu kadar, denizler ve deniz canlıları için de önemli bir tehdittir. Türkiye; Akdeniz, Ege, Marmara ve Karadeniz olmak üzere ekolojisi ve iklimi birbirinden farklı denizler ile çevrilidir. Türkiye’de su ürünleri yetiştiriciliği ile avcılığı, denizlerinde ve tatlı sularında yürütülen önemli bir geçim kaynağıdır. Ayrıca, taşımacılık, turizm, spor vb. faaliyetler denizlerinde ve sularında yapılan sosyo-ekonomik faaliyetlerdir. Türkiye denizlerindeki sıcaklık artışı, özellikle Akdeniz’deki sıcaklık artışı, denizleri tropik denizlere dönüştürmekte ve tropik denizlerden istilacı türler bölgeye göç etmektedir. Bu çalışmada, Türkiye denizlerindeki sıcaklık artışı ortaya konmaya çalışılacaktır. Bu değişim ışığında Türkiye denizlerinde olası değişimler ve iklim değişikliğinin denizlere ve su ürünlerine etkileri tartışılacaktır. Meteoroloji Genel Müdürlüğünün deniz meteoroloji gözlem sistemlerine ait, 1970-2021 yılları arasındaki ölçümlerinden alınan veriler ile Akdeniz, Ege Denizi, Marmara ve Karadeniz için analiz edilmiştir. Türkiye’yi çevreleyen denizlerdeki deniz suyu sıcaklarında (DSS), son yirmi yılda yaklaşık 0,4 – 1,4°C artış gerçekleşmiş olup bu dönem içinde maksimum artışların yaklaşık 2,3 – 3,5°C arasında olduğu da tespit edilmiştir. DSS’lerdeki en fazla artış Karadeniz’de tespit edilmiştir.

Pre-assessment of zoobenthos diversity from the only hard coral Marine Reserve in the Turkish Seas (Çanakkale Strait, Turkey)

Marine Protected Areas (MPAs) and their management have become more significant than ever due to the growing impacts of pollution, overfishing and illegal hunting activities in marine environments. Corals, as habitat forming species that create biodiversity hotspots, provide structural support, shelter and a nursery ground for associated biota. The present paper deals with the pre-assessment of invertebrate assemblages living in hard coral (Cladocora caespitosa) reef in the marine protected area (Dardanos Cladocora Reefs) of the Çanakkale Strait. In the study (DarINVERTA7) conducted between 2017 and 2021, 62 benthic invertebrate species, belonging to eight taxonomic groups were reported for the first time from the region of which five species (Clathria (Clathria) compressa, Rynchozoon neapolitanum, Hornera frondiculata, Polycitor adriaticus and Aplidium nordmanni) were new for the Turkish coasts.

Oceania armata Türünün Türk Sularındaki Muhtemel Havza Ölçekli Akıntı Kaynaklı Son Kaydı ve Diğer Jeli Organizmaların Yakın Geçmişteki Kayıtları

The present study reports the occurrence of Oceania armata in the Turkish Levantine Sea, and presents evidence to support a hypothesis established to link an increased recent and near-past records of many gelatinous zooplankton species in the Turkish seas, and particularly in the Turkish Levantine Sea to specific Mediterranean basin-scale currents (Atlantic-Ionian Stream and the Mid-Ionian Jet). One worldwide-distributed oceanic cnidarian specimen was collected from the surface water of a location of 36.59002 N and 29.02471 E by a SCUBA diver on January 18, 2019 in the eastern Mediterranean Sea. The hydrozoan specimen was then identified as O. armata and recorded for the first time in the Turkish Mediterranean coast and only second time in the Levant coast after about 30 years. This is the second report of the species from the Turkish waters, and the first report was from the Turkish Aegean coast. Recently, new records of the gelatinous species have increased from the Turkish marine coasts; Sea of Marmara, Aegean Sea, and Levantine Sea. Most of them are distributed in the West Mediterranean Sea, but are also present in the Adriatic Sea (East Mediterranean Sea). In the Mediterranean Sea, one branch of the Atlantic current (Atlantic-Ionian Stream) enters the eastern basin via the Mid-Ionian Jet, linked with the southern Adriatic current. Therefore, it is possible that zooplankton could have entered East Mediterranean by the Atlantic current through West Mediterranean.

Interstitial harpacticoid (Copepoda, Harpacticoida) fauna inhabiting mediolittoral zone of the Gulf of Saros (Turkey)

The study was aimed to reveal interstitial harpacticoid copepod fauna of the Gulf of Saros (Turkey), where no detailed research has been done before on this subject. The samples were collected from 30 stations located along the mediolittoral zone of the gulf between 2013 and 2014. As a result, a total of 72 species/subspecies belonging to 44 genera in 15 families were identified. All identified taxa except Tryphoema gallipoliensis Alper et al., 2018 are new records for the study area, besides 16 species were also recorded for the first time from the Turkish seas.

Kırmızı aslan balığı Pterois miles Bennett, 1828’in Ege Denizi’nin Türkiye kıyısı için maksimum boy kaydı ve bazı biyolojik özellikleri

Present work reports the maximum size record of Pterois miles for Turkish Seas with some additional biological information. The greatest individual of P. miles was caught off Çökertme Bight, Bodrum (Southern Aegean Sea) at 10 m depth with a spear gun on 15 July 2021. Captured individual of devil firefish was 34.0 cm in total length and 707.55 g in total weight. Specimen was male with a gonad weight of 13.6 g and it was determined to be 6 years old. A prey fish Chromis chromis were detected in the stomach in definable visible condition. Total length and weight of the mentioned individual are the greatest for the Turkish Seas among the reported studies up to date.

First Observations on the Stomach Contents of Devil Firefish, Pterois miles (Bennett, 1828) in the Gulf of Antalya, Turkey

The present study examined stomach contents of 35 individuals of Pterois miles (Bennett, 1828) captured using scuba diving gears in Antalya Gulf. Total length and total weight in the specimens of P. miles collected from the Gulf of Antalya were 13.1-35.2 cm (mean±SD; 19.98±4.40) and 36.88-456.6 g (mean±SD; 103.82±91.29), respectively. The dominant prey were fish (IFO=106.67%, IP=59.38%) and the rest were crustaceans (IFO=53.33%, IP=40.63%). It was determined that P. miles was carnivorous and predominantly piscivorous. This study is the first to show how kind of consumption preys P. miles obtained from the Gulf of Antalya. The result of this study strengthens the existing knowledge on the consumption preys of devil firefish in the eastern Mediterranean. The distribution of this species continues in the Turkish Seas. The fishery and consumption of lionfish should be improved. The development of a lionfish fishery could provide a management tool to ameliorate impacts to coastal ecosystems of the Mediterranean Sea.