Search

This study was conducted with the primary objective of determining the presence of both healthy and impacted Pinna nobilis populations along the European coasts of the Sea of Marmara, followed by the identification of P. nobilis abundance and survival rates in the region encompassing the Çanakkale Strait and the southern coasts of the Sea of Marmara. Underwater surveys were randomly conducted at 19 distinct stations, including 8 stations along the European coasts of the Sea of Marmara, 7 stations along the southern coasts of the Sea of Marmara, and 6 stations within the Çanakkale Strait. SCUBA diving equipment was utilized to record information on habitat structure, water temperature, depth, and visibility at each station. The transect length during underwater surveys and the number of transects at each station were determined based on the condition of the seabed and the size of the area, respectively. Throughout the study period (September 2021 and October 2023), water temperature fluctuated between 17.5°C and 26.6°C. At the end of the study, a total of 395 individuals (147 live, 248 dead) were observed, with live individuals exhibiting total lengths ranging from 16.4 cm to 50.9 cm. This study represents the first investigation into the spatial distribution of P. nobilis along the European coast of the Marmara Sea. The study contributes significantly to enhancing our understanding of the ecology of P. nobilis populations in both the Sea of Marmara and the Çanakkale Strait. Additionally, recommendations for the rehabilitation of impacted populations and the conservation of healthy populations have been provided for decision-makers and fisheries managers. [ABSTRACT FROM AUTHOR]

In this study, antioxidant radical scavenging capacity and total carotenoid content in the meat and shells of Pontastacus leptodactylus were investigated. Concerning the antioxidant scavenging effect, the highest IC50 values were found to be 388.77 mg g-1 and 155.53 mg g-1 for females and males in July and March, respectively. The mean IC50 values of the meat were calculated as 239.83 mg g-1 and 105.21 mg g-1 for females and males, respectively. The mean total carotenoid content in the meat was found to be 14.35 and 12.78 μg g-1 for females and males, respectively. The results indicated that crayfish meat had antioxidant radical scavenging capacity and was rich in carotenoid content. [ABSTRACT FROM AUTHOR]

The present study investigated the length-weight relationships and meat yield of narrow-clawed crayfish, Pontastacus leptodactylus (Eschscholtz, 1823), in Kocahidir Irrigation Reservoir. Between July 2015 and June 2016, a total of 653 individuals (255 females and 398 males) were sampled, and their carapace lengths (CL), total lengths (TL), and total weights (TW) were measured. The female-to-male ratio for the entire population was found to be 0.64:1.00. The results showed that the CL of the narrow-clawed crayfish ranged between 37 and 90 mm (39-79 mm for females and 37-90 mm for males), while the TW ranged from 10.10 to 165.61 g (11.13-90.01 g for females and 10.16-165.61 g for males). The TL of female individuals was 114.09 mm, with a weight of 40.43 g, while the TL of male individuals was 116.32 mm, with a weight of 53.45 g. The ratio of individuals above the minimum legal-size limit of 100 mm was determined to be 80.70% for the crayfish population in Kocahidir Irrigation Reservoir. Regression analysis indicated that the TL-TW and CL-TW relationships for female narrow-clawed crayfish exhibited negative allometric growth, while males showed positive allometric growth in terms of the TL-TW relationship and isometric growth in terms of the CL-TW relationship. Isometric growth was observed in the whole population for both male and female individuals in terms of TL-TW and CL-TW characteristics. Female individuals with carapace lengths ranging from 43-82 mm had a chelae meat yield of 2.48%, an abdomen meat yield of 11.38%, and a total meat yield of 13.85%. Male narrow-clawed crayfish with carapace lengths ranging from 35 to 90 mm had a chelae shear meat yield of 4.13%, an abdomen meat yield of 10.52%, and a total meat yield of 14.64%. [ABSTRACT FROM AUTHOR]

This study aimed to determine the length-weight relationship and condition factor of Prussian carp (Carassius gibelio, Bloch, 1782) from the Asi River. Samples were collected by 12-18 mm mesh sized fyke-nets between November and December 2021. Totally 88 specimens have been collected from the Turkish part of Asi River, Hatay, Türkiye. Lengths and weights ranged from 10.2 to 29.8 cm and 19.47 to 408.59 g, respectively. The b-values were calculated as 3.08 and the LWR equation was estimated as W = 0.0138*L3.08. The Fulton's condition factor (K) and the relative condition factor (Kn) values were calculated as 1.76±0.03 and 1.01±0.01, respectively. This study provides the valuable data on the length-weight relationship and condition factors of C. gibelio from the Asi River. The findings of the present paper revealed that C. gibelio showed an isometric growth and this region is relatively suitable for the growth of this species. Therefore, these data will be a valuable background for further biological studies and local fisheries management strategies. [ABSTRACT FROM AUTHOR]

A single specimen of the grey triggerfish, Balistes capriscus Gmelin, 1789, was caught by a speargun at 18 m water depth in the vicinity of the Çanakkale Strait in the Turkish Straits System, between the Aegean Sea and the Marmara Sea. Its total length was 57.8 cm and weight was 2270 g. The given size is the maximum observed length for the grey triggerfish, B. capriscus, in the Mediterranean Sea. In addition, this paper also documented the first confirmed record of the grey triggerfish, B. capriscus in the Çanakkale Strait (the Turkish Straits System). [ABSTRACT FROM AUTHOR]

This paper aimed to understand the potential effects of the mucilage event on the critically endangered Pinna nobilis in Ocaklar Bay located at the southern Marmara Sea. Underwater surveys were carried out in October 2020 and July 2021. The study area covers 500 m2 that was divided into 5 main zones having 100 m2 areas (10×10 m). Then, each main zone was separated into sub areas covering 25 m2 (5×5 m). The habitat structure, depth, and availability of the mucilage event were observed by SCUBA diving equipment in sub areas. During the underwater observations, the total number of dead and alive individuals was counted as 228 of which 130 individuals were alive and 98 were dead. The minimum and maximum population density (including both dead and alive individuals) of P. nobilis was found to be between 10 individuals per 100 m2 and 112 individuals per 100 m2 in the study area, respectively. The mortality rates were calculated as 35.96% and 16.12% for the years 2020 and 2021, respectively. This paper puts forward that the P. nobilis population could be resistant to extreme environmental stress and even juvenile individuals (smaller than 15 cm) were recruited in the study area during the mucilage event. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The population of Pinna nobilis (Linnaeus, 1758) has been severely damaged, especially by the effect of the disease, in addition to the causes such as fishing activities, overexploitation, environmental pollution, habitat degradation, tourism, and human impacts. Particularly, Haplosporidium pinnae caused gigantic destruction in the P. nobilis population. Accordingly, the present study aimed to determine the current status of the P. nobilis populations in the Çanakkale Strait. Samplings were carried out between July and August 2020 at 9 different stations in the Çanakkale Strait. The results revealed that mass mortality was observed at the two stations (Abide Beach and Kumkale Village Beach) located near the Aegean Sea. On the other hand, it has been determined that the lowest mortality rate (9.62%) has been found at Ilgardere station. Juvenile individuals have been observed in healthy and uninfected populations with high survival rates. This paper is the first document on the spatial distribution of P. nobilis in Çanakkale Strait. Therefore, the P. nobilis population should be continuously monitored to ensure the sustainability of the species. [ABSTRACT FROM AUTHOR]

An accurate estimation of the sea surface temperature (SST) is of great importance. Therefore, the objective of this work was to develop an adaptive neuro-fuzzy inference system (ANFIS) model to predict SST in the Çanakkale Strait. The observed monthly air temperature, evaporation and precipitation data from the Çanakkale meteorological observation station were used as input data. The Takagi–Sugeno fuzzy inference system was applied. The grid partition method (ANFIS-GP) and the subtractive clustering partitioning method (ANFIS-SC) were used with Gaussian membership functions to generate the fuzzy inference system. Six performance evaluation criteria were used to evaluate the developed SST prediction models, including mean square error (MSE), root mean square error (RMSE), mean absolute error (MAE), mean absolute percentage error (MAPE), Nash-Sutcliffe efficiency (NSE) and correlation of determination (R2). The dataset was randomly divided into training and testing datasets for the machine learning process. Training data accounted for 75% of the dataset, while 25% of the dataset was allocated for testing in ANFIS. The hybrid algorithm was selected as a training algorithm for the ANFIS. Simulation results revealed that the ANFIS-SC4 model provided a higher correlation coefficient of 0.96 between the observed and predicted SST values. The results of this study suggest that the developed ANFIS model can be applied for predicting sea surface temperature around the world. [ABSTRACT FROM AUTHOR]

Copyright of Yuzuncu Yil Universitesi Journal of Agricultural Sciences (YYU J Agr Sci) is the property of Yuzuncu Yil University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The objective of this paper is to determine the trend and to estimate the streamflow of the Gökırmak River. The possible trend of the streamflow was forecasted using an autoregressive integrated moving average (ARIMA) model. Time series and trend analyses were performed using monthly streamflow data for the period between 1999 and 2014. Pettitt's change point analysis was employed to detect the time of change for historical streamflow time series. Kendall's tau and Spearman's rho tests were also conducted. The results of the change point analysis determined the change point as 2008. The time series analysis showed that the streamflow of the river had a decreasing trend from the past to the present. Results of the trend analysis forecasted a decreasing trend for the streamflow in the future. The decreasing trend in the streamflow may be related to climate change. This paper provides preliminary knowledge of the streamflow trend for the Gökırmak River. [ABSTRACT FROM AUTHOR]

The main purpose of this study is to monitor shoreline changes of Atikhisar Reservoir in Çanakkale, Turkey. Geographic information system (GIS) and remotely sensed multispectral Landsat satellite images for the period of 1975-2017 were used to determine the shorelines. Satellite imageries were processed and analysed by remote sensing and GIS software. Then satellite images were imported into GIS software and the shorelines were manually digitized by using visual interpretation techniques for evaluating temporal changes in the shorelines. As a result, total length of the perimeter was calculated 18.8km in 1975 while 23.1km in 2017. The shoreline has reached the minimum perimeter in 1985 and the maximum perimeter in 1998. Shoreline has fluctuated during monitoring period and maximum decrease has been observed in 1985 with 35.3% decline while maximum increase has been observed in 2009 with 55.6% increase. The shoreline presents a trend that has complex non-sinusoidal waveform between the periods 1995-2000, 2002-2007, and 2009-2014. In the monitoring period, the shoreline has reached the negative peak in 1985, 1986, 2001, 2008, and 2014. It can be concluded that the shoreline has a trend that 6-yearly circle to reach positive and negative peaks. In conclusion, significant variations were detected in the shoreline. These variations could be affected by climate change, anthropogenic/agricultural activities, and sediment transportation. This paper provides the first knowledge and the most temporally rich assessment of shoreline changes in Atikhisar Reservoir. Therefore, continuous monitoring is vital for taking due precautions to support sustainable management of water resources in the future. [ABSTRACT FROM AUTHOR]

Spatial and temporal changes in surface area of Atikhisar Reservoir were monitored by using remote sensing and geographic information system techniques from 1975 to 2017. Satellite images were processed, analysed and manually digitized to reveal the changes in surface area of the reservoir. The results showed that total surface area of the reservoir was ranged between 1.72km2 and 3.84km2 during the monitoring period. Maximum increase in the surface area has been observed with 74.6% while maximum decrease has been observed with 31.8%. These fluctuations could be related with the climatic changes, natural and man-made processes such as sediment transportation, water leakages, excessive water exploitation for drinking, domestic or agricultural purposes, and human interventions along the reservoir. Therefore, surface area should be monitored continuously and all factors influencing the variation in surface area should be considered in decision making processes to support water sharing policy toward the management of water resources. [ABSTRACT FROM AUTHOR]

Length-weight relationships (LWRs) of 49 fish species belonging to 18 families from the shallow waters (0-20 m) of Gökçeada Island were reported. Fish specimens were sampled monthly with a beach seine (0-2 m) and beam trawl (5-20 m) between June 2013 and June 2014. The b values estimates varied between 2.66 and 3.59. Five of the 49 species (Arnoglossus kessleri, Scorpaena maderensis, Symphodus ocellatus, Symphodus rostratus, and Gobius geniporus) presented maximum length values that exceeded their maximum lengths listed in FishBase. [ABSTRACT FROM AUTHOR]