2021-Volume 2, Issue 1

Issue Full File

Cover, Editorial Board, Indexing, Table of Contents

Two individuals of Pontastacus leptodactylus (Eschscholtz, 1823) were collected from Atikhisar Reservoir in Çanakkale, Turkey. The individuals were caught by using a fyke-net. The fyke-nets were collected after 3-days soaking time from the reservoir on 18 July 2020. The sampling was carried out during the daytime. The sediment of the sampling location had a muddy substrate. Both blue colored individuals of crayfish (Pontastacus leptodactylus) were female. Blue color anomaly was observed in all parts of the bodies of both individuals. Morphometric characteristics were measured and the total lengths were 104.83 mm and 76.92 mm, and weights were 36.09 g and 11.76 g, respectively. The genetics of the mutant species should be examined in future studies to better understanding of the main factors causing color anomalies.

Data envelopment analysis is used when it is difficult to measure the relative effectiveness of organizational decision-making units due to a large number of similar inputs and outputs. Firstly, data envelopment analysis was discussed in this study. In this context, relative activities of 10 companies have been operating in fisheries sector for last nine years (2009-2017) which entered the Fortune 500 in Turkey and have sufficient data were measured using financial inputs and outputs. Relative effectiveness scores were obtained by examining the financial inputs and outputs of the companies that are in the Fortune 500 and operating in fisheries sector. In the second part of study, to reveal the technical efficiency and the ineffective ones resulting from the scale, DEA models including the input-oriented CCR (Charnes, Cooper, and Rhodes) and BCC (Banker, Charnes, and Cooper) model were established and the above mentioned procedures were repeated. Finally, it was investigated whether an investment system based on DEA could be established or not. DEA Frontier and DEA Solver software, one of the special software of DEA, was used for the solution of models using in data envelopment analysis. As a result of the study, the average efficacy percentage was found to be 88% for CCR and 93% for BCC. For the data obtained during 2009-2017, six companies were found to be active according to the CCR model, while seven companies were found to be effective according to the BCC model. Also, the targets were determined to activate the inactive companies.

Perceived as an indicator of the balance in wildlife and clean nature, the Eurasian otter (Lutra lutra L.) is near-threatened due to the fact that its fur is valuable, the increase in environmental pollution, the decrease in wetlands, the rivers in their habitats are turned into channels. There are 86 rainbow trout (Oncorhynchus mykiss) farms legally licensed by the Provincial Ministry of Agriculture and Forestry Muğla - Turkey. Since otter meets 70% of its nutrient need from fish, it is seen as a predatory species by aquaculture producers. For this reason, it is necessary to work on establishing otter habitats and breeding farms jointly with rainbow trout farmers in order to eliminate the negative effects of both rainbow trout farms and Eurasian otters. In this way, Eurasian otters that are near-threatened, will be saved and also a different contribution will be made to our economy.

The aim of the present study is to investigate spawning and larval rearing of brown meagre (Sciaena umbra). This is an important species in the Mediterranean Sea because of its beauty, calm swimming, large otoliths, souvenir potential, aggregative behaviour, excellent flesh and accessibility. Although this species is regarded as Near Threatened (in IUCN Red List Status), the demand increases the fishing. Green water technique was used for rearing the brown meagre larvae. Diameter of eggs was recorded as 1457.31±47.29 µm. Yolk was homogenous with oil globules of 371.59±18.15 µm at the centre. Hatching process began after 39 hours. Hatching rate (HR) was observed as 92.17±0.24%, and larvae inflated swim bladder around 97.33±0.94%. The brown meagre juveniles reached to 40.08±1.98 mm of total length (TL) with 10.96±0.08 mm body height (BH) and 662.27±21.23 mg body weight (BW) after 55 days of post-hatching. Survival (SR) was recorded as 72.5±0.70% at the end of study. Since the brown meagre is a threatened species, with high economic interest, is a possible candidate for commercial aquaculture both food and restocking the depleted natural fisheries.

The sampling point of the research was determined as the shores of Çanakkale Strait, where fishing is dense. Seasonal sampling of European pilchard (Sardina pilchardus, Walbaum 1792) was made that caught by commercial fishing boats in Çanakkale Strait and rarely offered for consumption. Inductively Coupled Plasma-Optical Emission Spectrometer (ICP-OES) allows analysis of trace, minor and major concentration levels of the chemical element, was used to determine the amount of heavy metals in the samples. Analysis of Cadmium (Cd), Copper (Cu), Iron (Fe), Manganese (Mn), Lead (Pb) and Zinc (Zn) heavy metals in samples was performed by the United States Environmental Protection Agency (US EPA). Levels of Cd, Cu, Fe, Mn, Pb and Zn were determined in muscle tissues of European pilchard. In the samples, Cd values were detected only in autumn, Cu level was found highest in winter, Fe and Zn levels were highest in spring and the level of Mn was observed higher in winter. Pb has not been detected in fish muscle dough in any season. Mn level has been obtained above the limit values and Cd level was found under the offered limits. As a result, it has been determined that the heavy metal accumulation in the muscle tissues of European pilchard caught from Çanakkale Strait increased seasonally in parallel with the increase of pollution.

In this study, surface morphology and chemical structure of Pagrus pagrus (Linnaeus 1758) sagittal otolith from the shores of Gizli liman to Kefalos Cape in the north of Gökçeada Island, Turkey were investigated using scanning electron microscopy (SEM) and energy dispersion X-ray spectroscopy (EDS) analyses. According to the results of SEM analysis, the species was found to be over two years old. The age rings of P. pagrus were clearly identified on the otolith by SEM. According to the EDS results, it was examined that the element contents of age rings and regions between the sagittal otoliths obtained by EDS analysis. It was observed that calcium, carbon, and oxygen elements that form the calcium carbonate were the highest in EDS analysis. In addition, it has been found that the percentage of protein in ring structures, especially, in rings related to the age factor showed an increase. It can be said that this structural difference plays a major role in the clarification of age ring. Furthermore, the scandium (Sc) element was firstly discovered in the structure of the sagittal otoliths of P. pagrus from Gökçeada, Turkey. Scandium is one of the indicator elements in thermal regions. This study describes the presence of scandium trace element for the first time in the structure of otolith.

In this study, growth parameters of 648 specimens of Spicara maena hunted by small-scale commercial fishermen around Saros Bay between January 2016 and December 2016 were studied. Of the 648 specimens analyzed, 509 were female and 139 were male. The length-weight relationship was calculated as for females and for males. The von Bertalanffy growth equations were computed as =22.1 cm, k=0.27 , =-1.42 year for the females; =20.6 cm, k=0.39, , = –1.11 year for the males. The growth performance index () was found as 2.12 and 2.22 for the females and males, respectively. This study includes preliminary information on the growth of the blotched picarel in Saros Bay (Northern Aegean Sea, Turkey).

In this study, the adsorption change of products obtained by chemical modification of waste fish bones, which are a biogenic-induced apathetic source, has been examined. Histidine (MH) and tryptophan (MT) were used for chemical surface modification, and cationic paint was used as fuchsine adsorbent. Paint adsorption was performed in water. The adsorption of MH and MT products was determined as 0.48 and 0.69 in 6.76  dye solution. The amount that MH and MT modified materials removed from the solution was 35.46 and 50.71%, respectively. As a result, it has been determined that the apatite-induced bones have affected the adsorption capacities of dyers as a result of different chemical molecular modifications. Additionally, it has been determined that the molecules with different qualities and properties affect the balance of adsorption. It has been observed that unprofitable products were suitable for chemical modification and adsorption procedures thanks to surface modification. With the development of studies in this field, it can be said that waste-resourced products will contribute to environmental use with effective, qualified, and useful materials.

In this study, we discussed the size of devil firefish Pterois miles (Bennett, 1828) specimen obtained from commercial fishermen who trawl off the coast of Taşucu, Silifke (36°3’32.70”N; 34°3’51.33”E). The obtained specimen was 335 mm in total length, 258 cm in standard length, and 0.696 kg in weight. The dissected specimen was a mature male. The testicles were weighed as 20.77 g and are in the third maturity stage. Additionally, during scuba diving to the underwater cave of Mersin Silifke, Beşparmak Island, a group of devil firefish was photographed at depths less than 15 meters. Contrary to many records on the hard rocky bottom at depths more than 20 meters, it has been observed by us that many anglers on the dock of Mersin Taşucu port were catching the devil firefish together with sympatric pufferfish (Lagocephalus sceleratus) in shallow waters of sandy bottom less than 3 meters at depth.

In this study, a feeding experiment was conducted using different rations (25%, 50%, 75%, and 100%) of wheat flour protein instead of fishmeal in fry fish (Dicentrarchus labrax) feeds. In the experiment, an average weight of 2.33±0.2 g juvenile seabass was used. Seabass fries were fed with the experimental feeds for 60 days. The experiment was designed in triplicates. At the end of the experiment, the growth parameters and fatty acid composition of fish fries were examined. As a result, it was statistically determined that the use of wheat flour protein at a high rate had a negative effect on the growth parameters of the fish. Significant changes in fatty acid composition were also observed.

This research was carried out to determine the rooting performances of different rooting media (Soil, Peat and CoCopeat) on the cuttings of the plants of the Lavender (Lavandula angustifolia) Hemus, Sevtopolis and Drujba varieties and Super A variety plants (Lavandula intermedia). Cuttings were planted in three different environments in the greenhouse mediums. Rooting rate, root length, shoot number and shoot length were determined in the cuttings left for rooting for approximately 60 days. As a result of the research, the highest rooting rate was obtained from Lavandula intermedia Super A variety in cocopeat medium with 62%, and the lowest rooting rate was obtained from Lavandula angustifolia Sevtopolis and Drujba cultivars in soil environment. The highest root length was obtained from Lavandula angustifolia Sevtopolis variety in cocopeat medium with 3.32 cm, and the lowest root length was obtained from Lavandula angustifolia Hemus cultivar in soil environment with 2.34 cm. The highest number of shoots was obtained from Lavandula angustifolia Drujba variety with 7.93 in cocopeat environment, and the lowest shoot number was obtained from Lavandula intermedia Super A variety with 6.93 in soil environment. The highest shoot length was 5.90 cm in Lavandula angustifolia Sevtopolis variety in cocopeat environment and the lowest shoot length was 4.19 cm in soil environment from Lavandula angustifolia Hemus variety.

Total fat and fatty acid levels of Ulva linza (Linnaeus 1753), Enteromorpha flexuosa (Agardh, 1883), and Taonia atomaria (Agardh, 1848) collected from Viranşehir, Taşkıran, and Karaduvar coasts were determined. The total oil level of the samples was found to be 1.31-1.91%, 1.23%, 7.78% for U. linza, E. flexuosa and T. atomaria, respectively. The dominant saturated fatty acids are palmitic acid and stearic acid. The highest level of palmitic acid (32.27%) was found in E. flexuosa in Viranşehir beach. The highest level of stearic acid was found on the coast of Viranşehir (7.20%), U. linza. The highest level of ΣSFA was found in the U. linza species on Taşkıran coast (37.89%), and the lowest level was determined in the T. atomaria species on the Taşkıran coast (18.13%). It is oleic acid that has a high level of monounsaturated fatty acids. The highest level of this fatty acid (10.35%) was found in E. flexuosa species in Viranşehir beach. The highest level of ΣMUFA was found in the Viranşehir coast (16.67%) and the lowest level (11.39%) in the U. linza on the Viranşehir beach. The highest level of linolelaidic acid in polyunsaturated fatty acids was found in E. flexuosa in Viranşehir beach (3.34%). The highest level of linoleic acid (4.85%) was found in U. linza on the coast of Viranşehir. The highest level of ΣPUFA was found in T. atomaria on the Taşkıran coast (16.56%), and the lowest level (7.03%) was found in U. linza.