Coast Of Turkey Research Articles

Using social media to identify recreational bluefish angling in the Mediterranean and Black Sea

Filling the information gap on recreational fisheries is an important challenge due to difficulties in monitoring and collecting data. The use of citizen science based on social media has recently emerged as a digital data source. This study aims to explore the extent of recreational bluefish angling in the Turkish coasts of the Mediterranean and adjacent seas (Aegean Sea, Marmara Sea and Black Sea) by using existing knowledge that is publicly available on YouTube and to highlight conservation priorities. For this purpose, a total of 14,214 bluefish individuals were identified from 929 YouTube videos posted between 2017 and 2019. The highest number of videos were uploaded from the Aegean Sea and the Marmara Sea with 47% and 40% respectively. Our results show that juvenile bluefish were predominantly caught in the Marmara Sea during the bluefish migration that occurs from the Black Sea to the Aegean Sea in autumn and from the Aegean Sea to the Black Sea in spring via the Marmara Sea. In addition, recreational bluefish anglers predominantly caught adult bluefish throughout the year in the Aegean Sea. This is likely related to the aggregations of bluefish around sea-cages along the Aegean Sea coast of Turkey. These results highlight conservation and management priorities for recreational bluefish angling for policymakers, and therefore prove the suitability of digital data extracted from social media.

Club convergence and drivers of house prices across Turkish cities

PurposeThis paper aims to examine the convergence pattern of residential house prices in a panel of 55 major cities in Turkey over the period between 2010 and 2018 and to investigate the determinants of convergence club formations.Design/methodology/approachThe authors applied the log t-test to identify the convergence clubs and estimated ordered logit model to determine the key drivers.FindingsThe results suggest that there are five convergence clubs and confirm the heterogeneity of the Turkish housing market. Istanbul, the commercial capital, and Mugla, an attractive tourist destination, are at the top of the housing market and followed by the cities located in the western part, particularly along the Aegean and Mediterranean coasts of Turkey. Moreover, the ordered logit model results point out that the differences in employment rate, climate, population density and having a metropolitan municipality play a significant role in determining convergence club membership.Practical implicationsLarge-scale policy measures aiming to increase employment opportunities in rural cities of central and eastern provinces and providing lower land prices and property taxes in the metropolitan cities of Turkey can help mitigate some of the divergence in the house prices across cities.Originality/valueThe novelty of this study lies in employing a new data set at the city level containing 55 cities in Turkey, which is by far the largest in terms of city coverage among emerging market economies to implement the log t-test. It also contributes to the literature on city-specific determinants of convergence club formation in the case of an emerging economy.

Comparative Voyage-Based Evaluation of Yacht Transfer by Self-Sailing and Cargo Vessel Shipment – A Pilot Study

The seasonal domestic yacht traffic direction in Turkey from the Marmara Sea and South coasts of Turkey at the beginning of the Summer and opposite direction at the end of the Summer or beginning of the Autumn. Considering the long-distance and long sailing time between the routes of seasonal yacht moving, this study revealed whether the yacht carrying in domestic shipping can be feasible for yacht owners and ship owners. The technical and managing perspective of port and ship selection criteria are indicated for yacht carrying. Estimations are done for the selected sample ship and yacht model and selected loading/discharging ports. All of the voyage expenses are formulated and written in MatLab. The voyage costs of the sample ship and yacht model are estimated to evaluate the feasibility of yacht carrying between the Bodrum and Haydarpaşa Port. The cost of a yacht carrying between the ports is acceptable depends on the number of yachts, speed of yacht and yacht type carried. The long coastline and yacht traffic potential of Turkey give the opportunity of effectiveness for shipping of yachts in the domestic line.

The biology and ecology of the invasive silver-cheeked toadfish (Lagocephalus sceleratus), with emphasis on the Eastern Mediterranean

Invasive species pose threats to either human health or inflict ecological and/or economic damage. The silver-cheeked toadfish (Lagocephalus sceleratus), a Lessepsian species, is one of the most harmful species in the Mediterranean Sea, because of its potent neurotoxin, impacts on marine biodiversity, and the increased costs and labor they inflict on fishers. Since the catch and consumption of this pufferfish is prohibited by almost all countries bordering the Mediterranean, they have now expanded into the entire Mediterranean and Black Sea. We performed a comprehensive study of L. sceleratus covering ecological aspects, growth, reproduction, diet and trophic level based on samples from southwestern coasts of Turkey. The estimated growth parameters were L∞ = 88.7 cm, K = 0.27 year-1, C = 0.6 and WP = 0.1. Their sex-ratio was M/F = 1:0.69. Lagocephalus sceleratus appears to be a batch spawner with discontinuous oocyte recruitment and has different spawning seasons in the Eastern Mediterranean which seem to be based on temperature cues which get shorter in duration as one moves north from the Suez. We also report their first positive ecological trait, that they are controlling some other invasive species through their diets, such as lionfish, Red Sea goatfish, rabbitfish and longspine sea urchins, in addition to controlling themselves through cannibalism, which appears to be density-dependent. They are indeed a top predator in the region with a trophic level of 4.1. We suggest that targeted fishing using improved gear-types to reduce fishing gear damages are initiated, and that finding commercial markets for pufferfish could help to naturally fund ongoing control efforts.

Age structure of stranded Loggerhead Turtles (Caretta caretta) in Turkey

The Mediterranean coast of Turkey includes important nesting beaches and marine habitats for the Loggerhead Turtle (Caretta caretta). We studied the demographic structure of this population by applying the skeletochronological method on stranded individuals. The mean age of stranded turtles was 27.0±3.83 years for females (N=10) and 40.1±14.97 years for males (N=7). The age of first reproduction was 23 years with a curved carapace length (CCL) of 61 cm for females and 21 years with a 67.5 cm CCL for males. The oldest observed female was 34 years old with a 67.8 cm CCL, while the oldest male was 59 years old with a 77.0 cm CCL. Incidental capture in fishing gear (60%) and marine vessel collisions (24%) were determined as the main causes of stranding.

Alien Species Threat across Marine Protected Areas of Turkey—An Updated Inventory

This study presents the first comprehensive assessment of alien species occurrences within the selected 11 Marine Protected Areas (MPAs) located on the Aegean and Levantine coasts of Turkey. The inventory includes a total of 289 species belonging to 15 phyla, in which lowest and highest diversities were observed in Saros Bay MPA (27 species, northern Aegean Sea) and Fethiye-Göcek Bay MPA (150 species, northwest Levantine Sea), respectively. Alien species distributions that were revealed in protected areas located in the southern Aegean and Levantine Seas were 56.9% similar (based on presence vs. absence data), while northern Aegean sites formed another distinct group. According to the breakdown of major phyla through the entire study areas, Mollusca had the highest alien diversity (22.1% of alien species), followed by Actinopterygii (19.0%), Arthropoda (15.2%) and Annelida (13.5%). Casual aliens were represented by very low proportions in each MPA, proving that most species were already established in the region, with a significant proportion of invasive species. Regardless of the localities, the majority of the species originated from the Red Sea, whose primary pathway of introduction is the corridor, the Suez Canal. In the absence of effective management actions against bioinvasions, MPAs located along the Turkish coastline do not currently seem to provide any protection, revealing a large conservation gap to be filled.

Distribution and Fishery of the Invasive Blue Crab (Callinectes sapidus) in Turkey Based on Local Ecological Knowledge of Fishers

This study provides information on the distribution and ecology of Callinectes sapidus in Turkey, as well as its maximum daily catch in set nets (trammel nets and gillnets), and its commercial fishery in lagoons. Data were collected in 2020 by utilizing a telephone based questionnaire survey. Responses were gathered from fishers (n = 6) who fish in the lagoons and the head of fishery cooperatives or its members (n = 104) in 28 cities, including the coastal regions of the Mediterranean Sea (Levantine), Aegean Sea, Sea of Marmara and the Black Sea in Turkey. Results indicated that C. sapidus is commonly distributed along the Levantine and Southern Aegean coasts of Turkey, whilst it is rarely observed in the Sea of Marmara and the Black Sea. It has been reported by fishers that this species has been seen in the Black Sea for the last decade. The maximum daily catch of blue crab in set nets showed a significant difference in the Levantine and Aegean coasts. The species is mainly produced in the lagoons, whereas many coastal fishers returned it as discard and 79% of fishers emphasized that C. sapidus shred the nets and caused an economic loss. Ovigerous females have been observed between March and October and we have discussed related management issues including current fishery season.

Köyceğiz-Dalyan Lagün Ekosistemi Kefal Populasyonlarının Büyüme Performans İndeksleri

As it is common in tropical and temperate zones, mullet species constitute the most important fish species caught along the coast and estuaries of Turkey. In terms of ecology, tourism and and fish productivity (52 kg/ha), Koycegiz-Dalyan Lagoon Ecosystem (KDLES) is the most important lagoon, with a 5500 ha surface area, is the Mediterranean Coast of Turkey. In the dalyan (barrier fish trap) systems; approximately 225 tons (80-405 tons) of mullets are caught to obtain 5 tons of dried fish eggs per year. Seventy percent of fish production in the lagoon is composed of mullets. The mullet samples were collected monthly between October 1992 and September 1994 from eight stations (one of them is a marine station) by trammel nets. The ages were determined using by scales anda ge composition varied form 0 to 6 ages. Species composition of 1159 sampled individuals were proportionally determined as Mugil cephalus 45%, Liza aurata 35%, Liza saliens 14%, Liza ramada 12%, Chelon labrasus 6%. The growth performance indices calculated from von Bertalanffy growth parameters using by all individuals for the M. cephalus, L. aurata, L. saliens, L. ramada and C. labrasus were determined as 2.957, 2.866, 2.692 and 2.719, respectively. The highest growth performance index was calculated for M. cephalus. The growth performance indeces of mullet species in Köyceğiz-Dalyan Lagoon Ecosystem were found around the world averages.

Türkiye’deki barbungiller balıkçılığının TÜİK mikro-veri setine dayalı olarak değerlendirilmesi

Although goatfishes (Mullidae Rafinesque, 1815) are among the most important commercial fishes in Turkey, no research has been found investigating the characteristics and spatial patterns of goatfish fishery. Here, we assessed the goatfish fishery of Turkey based on the microdata set of Turkish National Fishery Statistics gathered by Turkish Statistical Institute (TÜİK) between 2014 and 2017. In this context, we investigated the variation of total goatfish catch by cities. In addition, we compared the contribution of small (boat <10m) and large scale (boat >10m) fishers as well as different fishing techniques to the total goatfish catch in Turkey. Finally, an evaluation was made on the discard rates recorded in the official landing statistics. The results showed that higher red mullet (Mullus barbatus Linnaeus, 1758) catch was reported in the eastern Mediterranean, whereas surmullet (Mullus surmuletus Linnaeus, 1758) catch was significantly higher in the western Black Sea. On the other hand, fishery-independent investigations revealed that the Turkish fishery fleet mostly catches red mullet throughout the coasts of Turkey. Therefore, the separate records of red mullet and surmullet in the landing statistics likely represent the local names of red mullet rather than two different species. Large scale fishers were the main source of fishery pressure in the Mediterranean Sea, the Aegean Sea and the Black Sea. However, the majority of the catch was landed by small scale fishers in the Marmara Sea. The bottom trawl fishery landed 88, 92 and 87% of total goatfish catch in the Black Sea, the Aegean Sea and the Mediterranean Sea, respectively. Purse seiners provided the largest part of total goatfish catch (40%) in the Marmara Sea, where the bottom trawl fishery is prohibited. The overall average for the discard rate was found to be 0.47%. There were no statistically significant differences among the discard rates of two species, marine regions or fishing methods.

After four decades—Occurrence of the daggertooth pike conger, Muraenesox cinereus (Actinopterygii: Anguilliformes: Muraenesocidae), in the Mediterranean Sea

In October 2020, a single specimen of the daggertooth pike conger, Muraenesox cinereus (Forsskål, 1775), was caught by longline at a depth of 120 m, from the Mediterranean coast of Turkey. This species has been recorded from the Mediterranean for the second time after approximately four decades. This new finding shows that the distribution of the species has expanded.

After four decades—Occurrence of the daggertooth pike conger, Muraenesox cinereus (Actinopterygii: Anguilliformes: Muraenesocidae), in the Mediterranean Sea

In October 2020, a single specimen of the daggertooth pike conger, Muraenesox cinereus (Forsskål, 1775), was caught by longline at a depth of 120 m, from the Mediterranean coast of Turkey. This species has been recorded from the Mediterranean for the second time after approximately four decades. This new finding shows that the distribution of the species has expanded.

Composition and abundance of benthic marine litter in the fishing grounds of Iskenderun Bay, northeastern Levantine coast of Turkey

The anthropogenic marine debris in the Mediterranean Sea represents a growing concern because of its potentially harmful impact on marine ecosystems. In this paper, we investigated the composition of marine debris in the Iskenderun Bay seafloor. Between November 2009 and April 2010, a total of 34 trawl operations were conducted. Hauls lasted 60–385 min, and the towing speed varied between 2.7 and 2.8 knots. The estimated average marine litter concentration was 450.94 item/km2 (90.34 kg/km2). Plastic was the dominant material type (87%) at all stations. Single-use plastic items represented about 74.9% of the total marine litter. Our results showed that there is severe plastic pollution on the seafloor of Iskenderun Bay that may cause significant damage to both the fisheries sector and the marine environment.

How pollution effects the immune systems of invertebrate organisms (Mytilus galloprovincialis Lamark, 1819)

Hemocytes are the main immunologic parameters for invertebrate organisms as a response to diseases and pollutions. This study was aimed to reveal the relations between pollution and the total and differential hemocytes numbers. The gulf of İzmir was selected as location for sampling due to its contaminated by different anthropogenic pollutants mainly industrial effects. The effects of the pollutants were investigated on the mussels that have been collected from eight stations in the Izmir Bay (1- Inciralti, 2- Göztepe 3-Konak-4- Pasaport 5-Alsancak, 6-Karşıyaka, 7-Bostanlı), which are known as the most polluted part of inner Bay of Izmir (Western Coast of Turkey) and 8-Foça, (an anthropogenically industrialized and shipping -impacted area). The pollution effects in the bay were determined on hemolymphs by biomarkers such as total hemocyte counts (THCs) and differential hemocyte counts (DHCs).Microscopic examinations have shown the statistical differences at THCs and DHCs. The highest total hemocyte number was determined in the station 7 (Bostanlı) and the lowest in the station 4 (Pasaport) (P < 0.05). The number of total hemocyte counts were not differed significantly in the Stations among 2 (Göztepe), 5 (Alsancak) and 6 (Karşıyaka), and between Stations 8 (Foça) and 1 (Inciraltı) (P > 0.05). In addition, there have been significant differences in subpopulation according to differential hemocyte numbers. The results indicate that the station 8 (reference site-Foça) has the highest agranulocyte number while station 7 (Bostanlı) and the station 1 (İnciraltı) have the lowest agranulocyte numbers (P < 0.05). As for the basophilic hemocyte numbers, this situation was reversed highest number in station 1 (Inciraltı) and 7 (Bostanlı) and lowest in the station 8 (Foça) (p < 0.05). The station 4 (Pasaport) has the highest eosinophilic hemocyte number while station 8 (Foça) has the lowest.We concluded that differential hemocytes counts are more sensitive as biomarker with the highest numbers of agranulocytes and lowest numbers of eosinophilic and basophilic hemocytes in reference site.

Occurrence of the Histioteuthis reversa (Verrill 1880), (Cephalopoda/Histioteuthidae) in the Gulf of Mersin/ Turkey

A different species of squid was caught during trawling (36°01’390’’N; 033°44’220’’E and 36°07’080’’N; 034°00’920’’E) in the Gulf of Mersin at average depth of 300-400 m. It was determined that this squid was Histioteuthis reversa (Verrill 1880). This is the first record of Histioteuthis reversa both for the Gulf of Mersin and Turkey's Mediterranean coast.Keywords: Coast of Turkey, Mediterranean, Priacanthus sagittarius, Spread.

First Observation of the Nocturnal Cleaning Relationship between Common Octopus Octopus vulgaris (Cuvier, 1797), and Indo-Pacific Palaemonid Shrimp, Urocaridella pulchella Yokeş &amp; Galil, 2006 from the Iskenderun Bay, Eastern Mediterranean Coast of Turkey

During a Scuba survey in Iskenderun Bay at night time on November 2018, a female Urocaridella pulchella individual was observed with nocturnal cleaning on Octopus vulgaris at 16 m in depth. Some photos of the shrimp and its symbiont were taken. Although the nocturnal cleaning relationship between U. pulchella and various marine species has been reported in some studies, the nocturnal cleaning relationship between O. vulgaris and U. pulchella has been observed for the first time. In addition, in the present study, we first reported Indo-Pacific palaemonid shrimp U. pulchella which was encountered in its natural habitat during an underwater observation from Iskenderun Bay, and this report is the first observation for this area and fills a gap in the distribution range of this species.Keywords: eastern Mediterranean, Iskenderun coast, nocturnal cleaning, Palaemonidae, Turkey.

Analysis of Sea Water Temperature Change on The Coast of Turkey with GIS and Evaluation of Its Ecological Effects

Deniz suyu sıcaklıklarındaki artış sucul canlılarda ekolojik problemlere yol açabilmektedir. Bu düşünceden hareketle yapılan çalışmada; Türkiye’nin kıyıları boyunca yaşanan deniz suyu sıcaklığı artış oranları değişimi yıllık bazda irdelenerek, coğrafi bilgi sistemi ile değerlendirilmesi yapılmıştır. Araştırmada kullanılan veriler, Tarım ve Orman Bakanlığı Meteoroloji Genel Müdürlüğünden temin edilmiştir. 1970- 2019 yılları arasında Karadeniz, Akdeniz, Ege ve Marmara denizi, deniz suyu sıcaklık verileri irdelenmiş ve 50 yıllık analiz sonuçları ArcGIS ortamında işlenerek deniz suyu sıcaklıkları haritası oluşturulmuştur. Yapılan çalışma sonucunda; 1970 yılından 2000 yılına kadar ki süreçte deniz suyu sıcaklığı ortalamalarının değişim trendinin birbirine yakın ortalamalarda devam ettiği, 2000-2010 yılları arasında bir önceki dönem periyoduna (1990-1999) oranla Karadeniz’de 0,8°C, Akdeniz’de 0,5°C, Marmara ve Ege denizlerinde 0,4°C‘e deniz suyu sıcaklığı artışı gözlendiği, deniz suyu sıcaklığı ortalamalarındaki yükselişin özellikle 2010-2019 döneminde belirginleştiği görülmüştür. 1970-1979 yılları ortalama deniz suyu sıcakları ile 2010-2019 yılları ortalama deniz suyu sıcakları karşılaştırıldığında; ortalama deniz suyu sıcaklığının Karadeniz ve Akdeniz de 1,2°C, Ege denizinde 0,9°C, Marmara denizinde ise 1,5°C arttığı gözlenmiştir. Deniz suyunda yaşanan bu sıcaklık artışının ekolojik dengeye olası etkileri tartışılmıştır.

Halacaridae (Acari: Prostigmata) of the Aegean Sea of Turkey (Çanakkale and Izmir)

This study is based on the material from Aegean Sea Coast of Turkey (Canakkale and Izmir) at two sampling stations. As a result, 13 species belonging to 7 different genera were identified for the first time from the region. The following species are recorded: Agaue chevreuxi, Agaue panopae, Agauopsis brevipalpus, Agauopsis conjuncta, Agauopsis microhyncha, Atelopsalis pasifica, Copidognathus brachyostomus, Copidognathus remipes, Copidognathus tabellio, Halacaropsis hirsuta, Rhombognathus magnirostris, R. paranotops, and Simognathus adriaticus. Each species found in the locations were briefly described with comments on their habitat preferences and geographical distributions.

Recent Occurrence of Shortfin Mako Shark, Isurus oxyrinchus Rafinesque, 1810 (Chondrichthyes: Lamnidae), from the North-Eastern Mediterranean Coast of Turkey

A young individual of Isurus oxyrinchus was caught by a commercial longline off Dana Island (Mersin Bay, northeastern Mediterranean Sea) at a depth of 72 m on May 18th 2020. Morphometric measurements of the specimen were recorded and its photographs were taken. The examined specimen is now being preserved in the Museum of Systematics at Faculty of Fisheries of Mersin University, under the reference number MEUFC-20-11-132. This occurrence of a young female specimen reported in this study is adding a new location (Mersin Bay) from the Mediterranean's Turkish waters.

First Sighting of Prostheceraeus roseus Lang, 1884 and Tylodina perversa (Gmelin, 1791) in the Eastern Mediterranean, Turkey

A single specimen of Prostheceraeus roseus was recorded for the first time on 25 April 2019 from the Cevlik coast, Iskenderun Bay (Eastern Mediterranean, Turkey). After, other a single specimen of Tylodina perversa was observed during Scuba diving from the Keldag located within Cevlik (Eastern Mediterranean), at a depth of 12 m on rocky habitat covered with algae. The present finding is the first occurrence of Prostheceraeus roseus and Tylodina perversa from the eastern Mediterranean, Turkey. Although these species are live in the Mediterranean Sea up to date no specimens of these species reported in this easternmost coast of Turkey.

Türkiye'nin Akdeniz Kıyılarında Nadir Görülen Echeneis naucrates'in Son Kaydı

One specimen of live sharksucker was caught with a bottom trammel net in Taşucu Bay, south-eastern coast of Turkey, at 1 m depth on May, 2021. Meristic parameters were determined by fin ray counts and metric parameters were measured from the photos of the specimen. Excluding the recent record in Antalya Gulf, previous records of this species occurred later than May, generally in July in the Mediterranean Sea as well as in the Aegean Sea. The biometrical measurements were different in Taşucu Bay compared to those caught from the Aegean Sea and the central Mediterranean Sea (Tunisian and Sicilian waters), but relatively similar to those reported from Croatia. Major discriminative variables, albeit less significant in individuals from the central Mediterranean, were the number of anal, pectoral and dorsal fin rays. Numbers of suction disc laminae were higher in individuals from the central Mediterranean Sea and New Zealand than those from the Turkish coasts (all 21 disc laminae). The statistical analyses (Principal Component and Discriminant analyses) affirmed successful use of meristic parameters to differentiate the biometric characteristics of the species from the Aegean Sea, the central and eastern Mediterranean Sea. The length-weight relationship showed that the species had a negative allometric growth.