Determination of the perception of ship management towards environmental pollion caused by routine operations of ships

In order to leave a livable world to future generations, the elimination of environmental pollution, which is one of the important dimensions of sustainability, increases its importance every day. Undoubtedly, among the factors that cause environmental pollution, the role of ships is quite high. The seas are also polluted by the routine operation of ships as well as marine accidents. Pollution arising from the routine operations of ships is caused by the discharge of pollutants such as ballast water, bilge water, sludge or garbage into the sea. In addition, emissions from ships and oil and fuel pollution caused by the routine operation of ships also play an important role in environmental pollution. In this study, the phenomena resulting from the routine operations of ships and causing environmental pollution were examined using the Analytical Hierarchy Process (AHP) method, which is one of the multi-criteria decision-making methods, and the perceptions of ship operators towards environmental pollution were tried to be determined.

Investigation of maritime accidents in the strait of Istanbul in the perspective of navigational safety: İSTANBULMAX ship type recommendation

In this study, maritime accidents that occurred in the Strait of Istanbul over a 10-year period were evaluated in terms of ship-based risk factors. The frequency analysis was performed using the R - Studio program language. In this context, the accident data obtained from the Ministry of Transport and Infrastructure Main Search and Rescue Coordination Center were matched with the ship information accessed from Türk Loydu database. Thus, ship origin risk factors to be used within the scope of the study were determined and 10 different criteria were included in the analysis. These are ship length, ship breadth, ship draught, ship age, ship DWT, turning point, turning radius, L/B ratio, B/T ratio and number of propellers. The process of creating a data set was completed by spatially filtering the data and classifying of the ship-based causes accidents. The variables were examined with frequency analysis in the perspective of the Law of Large Numbers. With the results obtained, optimum characteristics based on ship origin risk factors have been revealed for each ship type that will pass through the Strait.

Toxicity of environmentally important micropollutants on three trophic levels

Micropollution is a serious environmental problem caused by continuous entry of trace quantities of toxic chemical substances into the aquatic environment. In the present study, three trophic levels of the aquatic ecosystems were used to evaluate the acute toxicities of environmentally important micropollutants including heavy metals, pesticides and drugs. There is a scarcity of information on toxicity of the studied substances on marine water algae. Among studied micropollutants, the most toxic chemical to Daphnia magna and Danio rerio was found to be 1-Chloro-2,4 dinitrobenzene with EC50 of 0.002 and 4.2 mg/L, respectively. Although this compound was also toxic to marine algae, Phaeodactylum tricornutum, arsenic showed the highest toxicity to the algae with EC50 of 2.4 mg/L. As compared to other organisms, D. magna was found to have higher sensitivity to all of the tested micropollutants.

First morphometry, reproduction, and genetic data for Blennius ocellaris (Linnaeus, 1758) from the Black Sea

Two specimens of the butterfly blenny, Blennius ocellaris, were caught off the coast of Ordu (Black Sea, Turkey) in April 2021 by trammel net. The aim of this paper is to further document occurrence and distribution of the butterfly blenny for the Black Sea and for Turkish marine ichthyofauna and to provide first morphometric, reproduction, and genetic data on this species to the Black Sea fauna species. Some morphometric and meristic characters were measured and presented as the percentage of total length (TL%). All morphometric measurements except eye diameter, pre-anal length, and maximum body depth were higher in the male individual. It was observed that the head makes up almost 1/4 of the body. It was determined that the ripe eggs were in their final stage of development (Stage IV). Gonad’s weight of a female individual was 2.85 g and the number of eggs was determined as 2993. The mean egg diameter was measured as 1070.7 ±15.63 μm (from 1050.2 to 1123.1 μm). The mitochondrial DNA gene regions of 16S rRNA and COI of the specimens were sequenced and analyzed. The generated partial sequences of COI and 16S rRNA were 621 bp and 551 bp, respectively. The maximum likelihood tree generated with the COI gene sequences retrieved from the GenBank database demonstrated geographic region-based distinction and sequences of the Black Sea specimens nested with the reference specimen sequences from the Western Mediterranean Sea and the Sea of Marmara.

Biological control of invasive zebra mussel (Dreissen polymorpha) in a freshwater ecosystem through Potamon ibericum

In the present study, possible effects of using Potamon ibericum for the prevention of zebra mussel (Dreissena polymorpha) invasion in a freshwater ecosystem were investigated. In a recirculating aquaculture system (RAS) supplied with aerated freshwater, 3 individuals of P. ibericum were placed in each of 3 aquariums provided by 100 zebra mussels. Throughout the 90-day monitoring study, mussel consumption was visually counted and then new mussels were introduced daily to complete the number of mussels to hundred, repeatedly each day. Throughout the monitoring study, growth rates, number of mussels consumed, and the number of broken mussel shell pieces were determined. Daily consumption rate of mussels by each crab was recorded as 11.115, 11.104, and 11.107 mussel/crab in the 3 experimental groups, respectively. The consumption rate of mussels per crab was counted as 999.78 over the 90-days experiment. As a result, the findings of this study provide strong evidence that P. ibericum can be used for

Analysis of accidents involved in touring/ sport/ recreational vessels and yachts in the Turkish search and rescue area

Our country is surrounded by seas on three sides; it is in an attractive position in terms of tourism due to its suitable climate and many history and cultures. Especially the stagnant structure of the Aegean and the Mediterranean allows sea tourism in almost four seasons; it is one of the routes preferred especially by yacht ships. In this respect, a maritime traffic arises due to touring, sports and recreational ships and yachts, and these ships occasionally cause accidents. In the study, marine accidents in the Turkish Search and Rescue Area involving touring, sports and recreational vessels and yachts are statistically analyzed. In this context, frequency distributions are carried out first and the hypotheses are examined by Chi-Square independence analysis.

Dietary incorporation of Sweet Potato Ipomoea batatas shoots improved growth performance and haematological profile of Tilapia Oreochromis niloticus in Hapa Nets

This study was conducted to evaluate the potential of sweet potato Ipomoea bata-tas powder (IbSPP), hot-water extracts (IbSPHWE) and crude ethanolic extracts (IbSPCEE) as growth pro-moter and immunoenhancer for tilapia cultured in hapa nets. Fish were divided ran-domly into four Treatments: T1 (control group) was fed a practical diet (PD) while T2, T3 and T4 were fed PD + IbSP powder (P), PD + IbSP hot-water extract (HWE), PD + IbSP Crude Ethanol Extracts (CCE), respective-ly. The growth indices and haematological profile of cultured fish were recorded after four months of feeding experiment. The final weight, weight gain, specific growth rate, condition factor, FCR, PER, FER were significantly higher in fishes that re-ceived PD +IbSPHWE than those that received either PD, PD + IbSPCEE or PD+ IbSPP only. The same trend was observed with the RBC, Hb, HCT, WBC and the PLT and its indices. The study has demonstrated that in-corporation of the hot-water extracts of I. batatas could improve the growth perfor-mance and increase immu-nocompetence of O. nilot-icus as evidenced by im-proved haematological pro-file.

The effects of electronic navigation devices on marine accident occurrences

In recent years, maritime-related organizations and companies have moved to a risk-based approach. To determine the risks, it is necessary to understand comprehensively why accidents occur and how it develops. The most effective measures need to be identified to implement the accident prevention measures successfully. According to the results of scientific studies conducted in the past, 80% of human factors risks were effective in marine accidents. Nowadays, maritime technologies are the most effective method for reducing the risks of human factors. However, the use of electronic navigation devices has not eliminated accidents. In this study, the accident reports for collision and grounding due to the electronic navigation devices' risk was evaluated using Human Factors Analysis and Classification System (HFACS) method. As a result of the study, more than half of the visible (active) causes of accidents have been identified as operating failure factors in electronic navigation equipment. Recommendations to prevent the occurrence of accident factors have been made.

The fishes of the Bolaman Stream, Northern Turkey

In this study, the fish species inhabiting the Bolaman Stream drains to the Black Sea from the Fatsa coast (Ordu Province, Turkey) was reported for the first time. The study was caught out non-periodically by sampling from seven stations in the Bolaman Stream between July 2017 and November 2018. Fish samples were captured with an electroshock device. With this study, it was determined that the fish fauna of the Bolaman Stream is represented by 10 species in five families (Acheilognothidae, Cyprinidae, Gobiidae, Leuciscidae, and Salmonidae). These species were as follows, respectively Rhodeus amarus, Barbus tauricus, Capoeta banarescui, Neogobius fluviatilis, Ponticola turani, Alburnus derjugini, Squalius cephalus, Vimba vimba, Alburnoides fasciatus, and Salmo coruhensis.

A review on maximum length of the greater weever Trachinus draco Linnaeus 1758 (Perciformes: Trachinidae) with a new maximum length from Oran Bay (Western Algeria)

On the 15th April 2017, one female specimen of the greater weever, Trachinus draco measuring 44.69 cm in total length and weighting 885 g was captured by trammel net in Oran Bay (Cape Rousseau) at 120 m depth. Up to date, this length is a new record of maximum length reached for this trachinidae for Algerian waters and the second maximum length recorded in Mediterranean basin according to Fischer et al., 1987 observation noted at 45 cm.