Ege Journal of Fisheries and Aquatic Sciences最新文献

{"title":"Biology, digestive enzymes and organosomatic indices of Chrysichthys nigrodigitatus (Lacépède, 1803) from Oyan Dam, Southwestern Nigeria","authors":"O. M. Oghenochuko, Fiyinfoluwa Georgina Leramo, Olamide Modinat Adeosun, Paulette Bangura, F. I. Adeosun","doi":"10.12714/egejfas.39.4.08","DOIUrl":"https://doi.org/10.12714/egejfas.39.4.08","url":null,"abstract":"Some aspects of the biology, digestive enzymes and organosomatic indices of Chrysichthys nigrodigitatus purchased from fishermen in Oyan dam was investigated. This study was aimed at providing information on the composition of food materials found in the gut and specific activities of selected enzymes as it affects the domestication of the species. 100 specimens of the species were examined for stomach contents, length-weight relationship, digestive enzyme assay and organosomatic indices, using standard methods. Food items observed were detritus (4%), fish part (12%), Insecta (13%). Sand was observed to be 11% of total stomach volume. The logarithmic equation for length-weight relationship lnW=2.68lnl-3.79 indicated that an increase in length led to a corresponding increase in weight with ‘R’ = 0.611, calculated ‘r’=0.78, ‘a’=2.68 and ‘b’=3.79 indicating positive allometric growth pattern. Amylase exhibited high activity in the stomach, while lipase and proteinase in the stomach and posterior intestine. Specific activities of digestive enzymes showed significant differences (p<0.05). Viscerosomatic (2.92± 0.25), hepatosomatic (2.27± 0.22) indices and Fulton condition factor (1.93± 0.06) were recorded. Feed items present in the species confirm its overlapping feeding habit, indicating that the species is an omnivorous detritivore. This was also depicted in the activities of the different digestive enzymes.","PeriodicalId":11439,"journal":{"name":"Ege Journal of Fisheries and Aquatic Sciences","volume":"4 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90440468","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Forecasting sea surface temperature with feed-forward artificial networks in combating the global climate change: The sample of Rize, Türkiye","authors":"Tamer Akkan, T. Mutlu, E. Baş","doi":"10.12714/egejfas.39.4.06","DOIUrl":"https://doi.org/10.12714/egejfas.39.4.06","url":null,"abstract":"The increase of the world population, especially in the global competition, together with the increasing use of fossil fuel resources to meet energy needs, leads to more greenhouse gases (more than one CO2, methane etc.) emissions and the global climate crisis. In this process, changes in meteorological events such as temperature, precipitation, and wind, attract attention moreover but when considered as a whole, we know that these negative changes in the ecosystem negatively affect many living groups. Sea Surface Temperature (SST) as measured meteorologically is the most important environmental parameter where these changes are monitored and observed. It draws attention to the fact that changes in SST are not limited to living organisms as habitats, but also catalyze many chain reactions, especially socio-economic impacts. Therefore, much of the work is devoted to forecasting studies to adapt to changing habitats and take the necessary precautions against potential risks. Feed-forward artificial neural networks have been commonly used to address these emerging needs. Artificial neural networks, which are a simple imitation of the human neurological system, have been used as an artificial intelligence method in forecasting problems due to their superior performance and not having the limitations of classical time series. In this study, the forecasting of the time series of monthly mean SST temperature obtained from Rize station between the years 2010 and 2020 is performed by using feed-forward artificial neural networks, and the forecasting performance of the corresponding time series is compared with many forecasting methods with different characteristics. The comparison of the methods used the mean square error and mean absolute percentage error criteria, which are commonly used in the forecasting literature. The analysis results showed that the analysis results obtained with the feed-forward artificial neural networks have the best prediction performance. As a result, it can be stated that the sea surface temperature can be forecasted with a very high accuracy using the feed-forward artificial neural networks.","PeriodicalId":11439,"journal":{"name":"Ege Journal of Fisheries and Aquatic Sciences","volume":"91 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85225589","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spatial variation in relationships of otolith measurements with body length of Prussian carp, Carassius gibelio (Bloch, 1782) collected from four lentic habitats in Samsun Province, Türkiye","authors":"S. Yılmaz, Refik Akbay, M. Özpiçak, S. Saygın, N. Polat","doi":"10.12714/egejfas.39.4.04","DOIUrl":"https://doi.org/10.12714/egejfas.39.4.04","url":null,"abstract":"This study aimed to disclose the spatial variability in the lagenar otolith (asteriscus) dimensions-total length relationships generated for four Prussian carp, Carassius gibelio (Bloch, 1782) populations (Altınkaya Dam Lake, Bafra Fish Lakes, Lake Ladik and Lake Simenit) in Samsun Province, Türkiye. Relationship between length and weight of the fish was also described for each population. Samples were obtained from commercial fishermen in different periods between February 2017 and March 2018. The length, height, and weight of each otolith were determined. A non-linear function was used to define allometric relationships between asteriscus measurements and body size. The slopes of the regressions acquired for the right and left otoliths at each sampling site did not show any significant difference. All of the relationships were found to be statistically significant (P<0.001). The r2 values ranged from 0.61 to 0.95, and the mean values of the percent prediction error varied from 3.10 to 7.45. The ANCOVA test determined significant spatial differences in regression slopes for the three otolith variables. Our findings revealed that otolith development reflected somatic growth, but this varied by sampling area.","PeriodicalId":11439,"journal":{"name":"Ege Journal of Fisheries and Aquatic Sciences","volume":"52 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88361983","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Integrated assessment with biomarker responses and metal concentrations on some fish species from İzmir Bay: A preliminary investigation","authors":"Mustafa Bilgin, Esin Uluturhan-Suzer, E. Darılmaz","doi":"10.12714/egejfas.39.4.03","DOIUrl":"https://doi.org/10.12714/egejfas.39.4.03","url":null,"abstract":"Antioxidant related biomarkers (superoxide dismutase, catalase, malondialdehyde) were investigated to evaluate metal (Hg, Cd, Pb, Cr, Cu, Zn, and Mn) bioaccumulation in some organs of fish species (Sparus aurata, Chelon labrosus, Diplodus vulgaris) from the İzmir Bay. Samples were collected at November 2019 from Inner and Outer Bays. Metal and biomarker analyses were carried out by Atomic Absorption Spectrometer and microplate reader, respectively. For metal analyses in organs, higher metal bioaccumulations were found at liver tissues. Higher Hg and Zn concentrations were found in S. aurata, higher Cd, Cr, Cu and, Mn concentrations were detected in C. labrosus and higher Pb concentrations were determined in D. vulgaris. In biomarker results, superoxide dismutase (SOD) and catalase (CAT) activities were generally higher in gills, however, MDA contents were higher at liver. The highest biomarker results were detected at C. labrosus. Statistical analyses were demonstrated that especially MDA content were expressed strong responses for the metal bioaccumulations. Also, Mn levels were considerably correlated with all biomarkers as expected. This study revealed that combined utilization of biomarkers and metal concentrations could be a vital indicator to investigate health status of the marine ecosystems.","PeriodicalId":11439,"journal":{"name":"Ege Journal of Fisheries and Aquatic Sciences","volume":"37 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80218344","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The remarkable observation for a mallard (Anas platyrhynchos) food from estuarine/coastal area (İzmir/Turkey): A mosquitofish (Gambusia holbrooki)","authors":"A. Salman, I. Kurtul, H. Sarı","doi":"10.12714/egejfas.39.3.03","DOIUrl":"https://doi.org/10.12714/egejfas.39.3.03","url":null,"abstract":"The purpose of this study is to create awareness about the species of mosquito fishes (Gambusia holbrooki Girard, 1859) both vectors and ways of introduction to new aquatic habitats. Because the species creates risks, especially for the circumstance of the native and endemic fish fauna, studies about introduction stories of the species are quite important to prevent the risk. In the current report, mosquitofishes which are known as a highly invasive species were found in the crop content of a hen mallard duck (Anas platyrhynchos L., 1758) in an estuarine area, the Gediz River Basin (İzmir, Turkey). This report is the first record of a duck consuming mosquitofish. Although nevertheless, it is known that mallard duck feeding behaviour does not predominantly contain fish (they mainly feed on plant seeds), according to this observation, mosquitofish might be added to the prey list of mallards as a new type of food. Therewith, this feeding behavior also indicates that ducks might be a potential vector for the transport of invasive mosquitofishes.","PeriodicalId":11439,"journal":{"name":"Ege Journal of Fisheries and Aquatic Sciences","volume":"20 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85049961","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A simple method for fish silage production: Using yoghurt as inoculum","authors":"A. S. Özkütük, G. Özyurt","doi":"10.12714/egejfas.39.3.11","DOIUrl":"https://doi.org/10.12714/egejfas.39.3.11","url":null,"abstract":"The evaluation of seafood processing wastes is an important issue in terms of both preventing environmental pollution and adding value to these wastes economically. The most practical method that can convert seafood processing waste into a valuable feed source and plant fertilizer is to make silage. In this study, the ripening times and nutritional components of fish silages prepared with direct addition of lactic acid bacteria culture (Streptococcus thermophilus), acidifying chemicals (formic acid) and yogurt, which is a fermented food, were compared. In the research, sardine fish (Sardina pilchardus) wastes (head, skin, bones, internal organs, etc.) were used in fish silage production. It was observed that all fish silages completed the ripening phase within a maximum of 10 days. It was determined that the moisture, ash, protein and lipid contents of the groups prepared with acid, bacteria and yoghurt ranged between 63-66%, 5.6-5.7%, 11.3-11.8% and 12.18-13.65%, respectively. As a result of the research, it was observed that fish silages made with the addition of yoghurt as an alternative to silages made with direct addition of pure bacterial culture or acid addition met the expectations in terms of both ripening time and nutrient components.","PeriodicalId":11439,"journal":{"name":"Ege Journal of Fisheries and Aquatic Sciences","volume":"181 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80227417","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Distribution of phytoplanktonic species in the sea snot in 2021 in the Marmara Sea","authors":"Levent Yurga","doi":"10.12714/egejfas.39.3.09","DOIUrl":"https://doi.org/10.12714/egejfas.39.3.09","url":null,"abstract":"Sea snot, which was seen and reported in the Adriatic and Tyrrhenian Seas in the early 1990s, had been on Turkey's agenda as an environmental massive disaster from the winter months of 2021 until the end of summer in the Sea of Marmara. Due to the magnitude and topicality of the subject, the samples collected from the coastal areas where sea snot is observed in Marmara from January until July were examined. According to the results obtained, 5 classes were determined in sea snot. Species of algae that secrete mucilage, which provides stickiness to the formation, were also been identified in sea snot. These are 1 dinoflagellate, 2 Prymnesiosides, 5 diatoms, and 2 cyanobacteria species. 8 toxic planktonic species were detected in sea snot: 1 causing PSP poisoning and 3 of dinoflagellate causing DSP poisoning; 1 of prymnesiophisid that releases ichthyotoxin to the sea environment, and 3 of diatoms that cause ASP poisoning.","PeriodicalId":11439,"journal":{"name":"Ege Journal of Fisheries and Aquatic Sciences","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82348820","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The invasive silver-cheeked toadfish, Lagocephalus sceleratus (Gmelin, 1789) appeared in the Sea of Marmara after more than a decade: A call for awareness","authors":"H. Bal, Ömerhan Dürrani","doi":"10.12714/egejfas.39.3.12","DOIUrl":"https://doi.org/10.12714/egejfas.39.3.12","url":null,"abstract":"This study presents a new locality record of poisonous pufferfish, Lagocephalus sceleratus (Gmelin, 1789), one of the 18 worst invader fish species identified globally by IUCN, from the Sea of Marmara caught by a commercial purse seine fishing vessel while fishing anchovy on 22 February 2021. Previously, this invasive species was first recorded at the Gelibolu peninsula in the Sea of Marmara between September 2007 and October 2008. Lagocephalus sceleratus recorded in this study is larger in size with 142 mm total length than previous records (126 mm in 2007; 95 mm in 2008) for the Sea of Marmara. The presently reported record represents the first documented occurrence of this species in the Erdek Bay of the Sea of Marmara and the third documented record for the entire Sea of Marmara.","PeriodicalId":11439,"journal":{"name":"Ege Journal of Fisheries and Aquatic Sciences","volume":"369 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77797544","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Growth performance, molting frequency and carapace coloration of marbled crab (Pachygrapsus marmoratus) in different salinity levels","authors":"Onur Karadal","doi":"10.12714/egejfas.39.3.08","DOIUrl":"https://doi.org/10.12714/egejfas.39.3.08","url":null,"abstract":"This study was conducted to evaluate the parameters on growth performance, molting frequency and carapace coloration of marbled crab (Pachygrapsus marmoratus Fabricius, 1787). Crabs were collected from Urla, İzmir. The experiment was performed in 10 L plastic containers filled with 6 L of seawater at four different salinity levels (5‰, 15‰, 25‰ and 35‰). Ten crabs with an initial mean weight of 0.78±0.03 g were placed in each container with three replicates. Crabs were fed once a day with a commercial diet (46% protein and 18% lipid) for 12 weeks. At the end of the study, the final mean weight (FMW) of the 25‰ group was significantly higher than the 5‰ and 15‰ groups (P<0.05). Specific growth rates (SGR) of the 15‰ and the 35‰ groups and feed conversion ratio (FCR) of the 25‰ group were significantly higher than the 5‰ group (P<0.05). The mean molting frequency (MMF) of the 25‰ group was significantly higher than the 5‰ group (P<0.05). Final lightness (L*) of the 5‰ and 15‰ were significantly lower than their initials (P<0.05). Final redness (a*) of the 25‰ group was the highest among the experimental groups (P<0.05). Final yellowness (b*) of the 25‰ group was significantly higher than the 5‰ and 15‰ groups (P<0.05). According to the results, it is recommended to keep the salinity at 25‰ under marble crab rearing conditions. Further studies are needed to reveal the potential properties of this species in marine aquariums.","PeriodicalId":11439,"journal":{"name":"Ege Journal of Fisheries and Aquatic Sciences","volume":"5 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74340380","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mass mortality report of the critically endangered Pinna nobilis (Linnaeus, 1758) in Gökçeada (North Aegean Sea, Turkey)","authors":"D. Acarlı, S. Acarlı, M. I. Öz","doi":"10.12714/egejfas.39.3.06","DOIUrl":"https://doi.org/10.12714/egejfas.39.3.06","url":null,"abstract":"In August 2020, a total area of 38000 m2 around Gökçeada has been scanned to determine the current population status of Pinna nobilis. 9 stations (Yıldızkoy, Manastır, Marmaros, Gizli Liman, Laz Koyu, Kapıkaya, Karaçavuş, Karaçavuş shore and Kefalos) have been detected by means of SCUBA and ABC diving techniques. All specimens were found dead (total mass mortality of 100%). The total length range of P. nobilis was between 30.8 – 38.3 cm.","PeriodicalId":11439,"journal":{"name":"Ege Journal of Fisheries and Aquatic Sciences","volume":"9 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90895902","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}