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This paper reported the first occurrence of the big-scale sand smelt Atherina boyeri (Risso, 1810) in the Atikhisar Reservoir, Çanakkale, Turkey. A total of 130 individuals of A. boyeri were caught using a beach seine with 10 mm mesh size, 1.5 long and 1 m high in June 2021. The total length and weight of specimens ranged between 3.2-9.1 cm and 0.17-4.38 g, respectively. This study provides valuable information about the spatial distribution of A. boyeri and the biodiversity of the reservoir. Further investigations should be carried out to determine bio-ecological features of A. boyeri population to understand its effect on the reservoir., Bu makale, gümüş balığının, Atherina boyeri (Risso, 1810), Atikhisar Baraj Gölü'nde (Çanakkale, Türkiye) ilk kaydını bildirmektedir. Haziran 2021'de 10 mm göz açıklığına, 1,5 uzunluğa ve 1 m yüksekliğe sahip ığrıp kullanılarak toplam 130 A. boyeri bireyi yakalanmıştır. Yakalanan bireylerin toplam boy ve ağırlıkları sırasıyla 3,2-9,1 cm ile 0,17-4,38 g arasında değişmektedir. Bu çalışma, A. boyeri'nin mekansal dağılımı ve rezervuarın biyolojik çeşitliliği hakkında değerli bilgiler sunmaktadır. A. boyeri stoklarının rezervuarda yerleşik popülasyon oluşturup oluşturmadığı ve popülasyon dinamiklerinin belirlenebilmesi için daha fazla araştırma yapılmasına ihtiyaç duyulmaktadır. Rezervuar üzerindeki etkisini anlamak için A. boyeri popülasyonunun biyo-ekolojik özelliklerini belirlemeye yönelik daha fazla araştırma yapılmalıdır.

The aim of the current study is to determine the fish biodiversity in the shallow waters (0 - 20 m) of Gokceada in the North Aegean Sea. The samples were collected monthly between June 2013 - June 2014 using by a beach seine (0 - 2 m) and beam trawl (5 - 20 m). Field sampling was carried out in two stages. A preliminary sampling survey was carried out in the first phase (March-April 2013). During this period, sampling was conducted in each station around the entire island where sampling gear was feasible to use, and the most productive sampling stations were determined. The second stage was the biodiversity monitoring work. During the study period, 13-monthly sampling surveys were carried out at six seine and dredge stations around the island. During the whole period, a total of 30509 individuals belonging to 80 species were sampled. From the seine samplings (0-2 m), 18702 individuals from 40 species were obtained. The beam trawl samplings (5-10 and 10-20 m) identified 11807 individuals from 66 species. Biodiversity indices were calculated, and species diversities and abundances were determined for the seasons. The most copious seasons in terms of number of species abundance was identified in fall and summer. Fish species diversity and abundance maps were generated for each station. As a result, it was determined that the coastal ecosystems of Gokceada, northern Aegean Sea, incorporated many important habitats that is rich in biodiversity. In addition, many commercial species that had been over-exploited in the region was determined to use these coastal habitats for feeding, breeding, sheltering, and growing.

Bu çalışmanın amacı Atikhisar Baraj Gölü'nde gerçekleşen kıyı çizgisi (KÇ) ve yüzey alanı (YA) değişimlerinin uzaktan algılama ve coğrafi bilgi sistemi kullanılarak belirlenmesi ve izlenmesidir. İklim değişikliğinin KÇ ve YA üzerindeki olası etkilerinin incelenmesi ve balıkçılık yönetimi açısından değerlendirilmesi de hedeflenmiştir. Bu kapsamda, 1975–2017 yılları arasındaki uydu görüntülerinden KÇ ve YA manuel olarak sayısallaştırılmıştır. Sonuç olarak, izleme dönemi boyunca KÇ uzunluğu 12,187km ile 31,7km arasında, YA ise 1,72km2 ile 3,84km2 arasında değişkenlik göstermiştir. Başlangıçtaki değerler ile karşılaştırıldığında KÇ uzunluğundaki en fazla azalma ve artış %35,3 ile %55,6 iken YA'da %38,1 ile %38,1 olarak hesaplanmıştır. KÇ ve YA arasında önemli bir ilişki (p

Water quality is one of the main characteristics of a river system and prediction of water quality is the key factor in water resource management. Different physical, biological and chemical parameters including heavy metals can be used to assess river water quality. Evaluation of the water quality in the rivers is quite difficult and requires more time and effort because of the fact that many factors affect water quality. Traditional data processing methods are insufficient to solve this problem. Therefore, in this study, an adaptive neuro-fuzzy inference system (ANFIS) model was developed to predict the concentrations of cadmium (Cd) in the Filyos River, Turkey. For this purpose, water samples collected at 7 sampling locations in the river during December 2014-2015 were used to develop ANFIS model. The available data set was apportioned into two separate sections for training and testing the ANFIS model. Developed models aimed to use the least parameters to estimate Cd concentration. As a result, a relatively higher correlation (R-2=0.91) was found between observed and modelled Cd concentrations. The results indicated that the ANFIS model gave reasonable estimates for the concentrations of Cd with a high degree accuracy and robustness. In conclusion, this paper suggests that ANFIS methodology produce very successful findings and has the ability to predict Cd concentration in water resources. The outcomes of this research provide more information, simulation, and prediction about heavy metal concentration in natural aquatic ecosystems. Therefore, ANFIS can be used in further researches on water quality monitoring.

A specimen of the garfish, Belone belone (Linnaeus, 1761), was caught in the coast of Gökçeada Island, the northern Aegean Sea along the Turkish coasts. Its total length was 93.3 cm and weight was 1120 g. The given size is the maximum observed length value of the species for the Aegean Sea and the other coasts of Turkey. Also, it is the second largest length ever reported in the all seas of the world.

Length-weight relationships (LWRs) of 49 fish species belonging to 18 families from the shallow waters (0-20 m) of Gokceada 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.

Bu çalışmanın amacı Gökçeada sığ sularında bulunan Sparidae ailesine ait genç balık türlerinin miktarları, yoğunlukları ve alansal dağılımları ile tercih ettikleri habitat yapılarının ortaya çıkarılması ve Coğrafi Bilgi Sistemi (CBS) ortamında modellenmesidir. Bu amaçla Haziran 2013–Mayıs 2014 ayları arasında toplam 6 istasyonda, ığrıp ve algarna kullanılarak 0-2 m, 5-10 m ve 10-20 m derinlikleri olmak üzere 3 farklı derinlik konturunda aylık olarak örneklemeler yapılmıştır. Örneklemeler sonucunda Sparidae ailesine ait 14 farklı türe ait toplam 7258 adet birey yakalanmıştır. Türlerin derinlik ve habitat tercihleri göz önünde bulundurularak yoğunlukları ve alansal dağılımları tahmin edilmiş olup CBS ortamında modellenmiştir. Genç Sparid türlerinin 0-2 m derinlikleri arasında en çok kumluk habitatları ve 10-20 m derinlikleri arasında deniz çayırları bulunan alanları tercih ettiği gözlenmiştir. Bu çalışmanın sığ sular ve genç balıklar üzerine yapılacak olan çalışmalar ile balıkçılık yönetimi konusunda yapılacak olan çalışmalar için önemli bir kaynak olacağı düşünülmektedir. The main purpose of this study was to determine the density, abundance, spatial distribution, habitat preferences and modeling of juvenile fish species belongs to Sparidae family spatial distribution in Gökçeada (Imbros) shallow waters with GIS. Samplings were conducted by monthly with a beach seine and a beam trawl in 6 different stations and 3 different water depth (0-2 m, 5-10 m and 10-20 m) between 2013 June to 2014 May. A total of 7258 fish were collected belongs to 14 species. The distribution and density of juvenile fishes were estimated considering the water depth and habitat preferences and also modelled by using GIS. It is observed that juvenile fish species most prefer the sandy areas in 0-2 m water depth and the seagrass areas in 10-20 m water depth. It is believed to be an important resource for the next studies about juvenile fishes and shallow waters in relation to fisheries management. 121