An Investigation on Fish Fauna in Lake Simenit (Terme-SAMSUN) Simenit Gölü (Terme-SAMSUN) Balık Faunası Üzerine Bir Araştırma

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1 F. Ü. Fen ve Mühendislik Bilimleri Dergisi, 15(4), , 2003 An Investigation on Fish Fauna in Lake Simenit (Terme-SAMSUN) Selma UĞURLU (HELLİ) ve Nazmi POLAT Ondokuz Mayıs Universitesi, Fen-Edebiyat Fakültesi, Biyoloji Bölümü, Kurupelit / SAMSUN Abstract This study was carried out between April 2000 and April 2001 in order to determine the fish species in Lake Simenit. Totally 292 specimens were caught by different methods. In this study, five species and one subspecies belong to three families (Mugilidae, Esocidae, Cyprinidae) were identified. The systematic characteristics of fish species were explained. Furthermore these characteristics were compared with those in previous taxonomical studies, and key to identification was also presented. Keywords: Lake Simenit, Fish, Taxonomy, Fauna Simenit Gölü (Terme-SAMSUN) Balık Faunası Üzerine Bir Araştırma Özet Simenit Gölü nde yaşayan balık türlerini ortaya çıkarmak amacıyla yapılan bu araştırma, Nisan 2000-Nisan 2001 tarihleri arasında gerçekleştirilmiştir. Toplam 292 örnek farklı metotlarla yakalanmıştır. Bu çalışmada üç familya (Mugilidae, Esocidae, Cyprinidae) ya ait beş tür ve bir alttür teşhis edilmiştir. Balık türlerinin sistematik karakterleri açıklanarak, daha önce yapılan taksonomik çalışmalarla karşılaştırmaları yapılmış ve tayin anahtarıda verilmiştir. Anahtar Kelimeler: Simenit Gölü, Balık, Taksonomi, Fauna 1. Introduction The numerous of fish species and other organisms have been feeding, growing and habiting at least one period of life in coastal lagoons. Coastal lagoons having biological and economical importance are rich point of view nourishment and naturel conservation areas. The knowledge about the fish species living in the lagoons provides possibilities to researches such as the protection of the stocks of fish which constitute a direct or undirect importance as human food and efforts for making them more productive [1]. There is no previous study conducted about the fish fauna in Lake Simenit. This lake is one of the major lagoons near Samsun and provides a part of the protein requirements of the people in the area. Fish species inhabiting Lake Simenit must be determined to a management for the future. This study has been realized to determine the fish species in Lake Simenit, to contribute to efforts seeking to benefit from fish with economic importance, and assist to similar future investigations. 2. Materials and Methods The study area is located in 25 km. to center of Terme in the province of Samsun. Lake Simenit, whose depth is between 0.5 and 3.0 m, surface area is 80 hectare, joins with the Black Sea by means of a canal at nortwest and Lake Akgöl by means of another canal at southeast [2]. Lake Simenit is formed a lagoon complex by Lake Akgöl has an average depth of 3.0 m and

2 S. Uğurlu ve N. Polat surface area of 50 hectare (Figure 1). The specimens examined in this study, were collected all over the lake. The following instruments were used to capture of fish: a long handled scoop net, an electric shock, fishing lines, trammel nets with different mesh size. The fish caught from Lake Simenit were preserved according to Balık [3]. The colours and features of patterns were recorded as well, and photographs were taken before they were fixed. Metric measurements were made by dial caliper with 95% confidence limits and a fish measurement scale. All meristic characteristics were counted by lancet, pens and fish needle under a stereoscopic binocular microscope. In order to determine the systematic positions of fishes inhabiting in Lake Simenit and prepare a key to identification, many references [4-15] were used. Figure 1. Map showing research area 3. Results 3.1. Systematic Location of Fish in Lake Simenit A total of 292 individuals caught from Lake Simenit were evaluated. As a result of this study, five genera, five species, one subspecies belonging to three families were identified. These species and subspecies have been classified according to FAO [6]. 486

3 An Investigation on Fish Fauna in Lake Simenit (Terme-SAMSUN) Phylum : Chordata Subphylum : Vertebrata Classis : Teleostei Superordo : Acanthopterygii Ordo : Mugiliformes Familia : Mugilidae Mugil cephalus Liza saliens Superordo : Protacanthoperygii Ordo : Salmoniformes Familia : Esocidae Esox lucius Superordo : Ostariophysi Ordo : Cypriniformes Familia : Cyprinidae Carassius auratus gibelio Tinca tinca Abramis brama 3.2. Key to the Identification of Fish in Lake Simenit 1. There are well-seperated two dorsal fins (Figure 2 and Figure 3). First dorsal fin with 4 unbranched rays...mugilidae...2 There is unique dorsal fin with branched and unbranched rays (Figure 4, Figure 5, Figure 6 and Figure 7) Adipose eyelid is well developed, covering the eye to the pupil and dorsal scales having single canal...mugil cephalus Adipose eyelid is weakly developed, not reaching the pupil and dorsal scales having 2-5 canals...liza saliens 3. Dorsal and anal fins far back (Figure 4), equal to subequal in size, and situated opposite one another. Jaw articulated behind the posterior edge of orbit. Teeth on jaws are large and prominent...esocidae...4 Dorsal fin is approximately middle of the body (Figure 5, Figure 6 and Figure 7). Fishes are without teeth on jaws, palatines, or vomer. The upper jaw is formed by the premaxillary bone only; 1 or 2 pairs of barbels sometimes present. Pharyngeal lie parallel to the gill rakers, are falciform, each with one, two or three rows of blunt teeth...cyprinidae Body elongate, lateraly compressed. Cheeks are usually fully scaled, opercles generally scaled on top of half only but variable (Figure 4). Head is large; snout is elongate, flat, and somewhat like a duck s bill...esox lucius 5. Dorsal fin with more than 12 branched rays is about two times longer than anal fin. Gill rakers on the first arch are Carassius auratus gibelio Dorsal fin with less than 12 branched rays is about equal or two times smaller than anal fin. Gill rakers on the first arch are Barbels are in one pair. Skin is thickned, slimy; the scales small, embedded, in lateral line. Anal fin having branched rays less than 10 is short...tinca tinca Barbels are absent. Large cycloid scales easily detached from skin. Lateral line with scales. Anal fin having branched rays more than 10 is long...abramis brama 3.3. Species and Subspecies Inhabiting Lake Simenit M cephalus, L. saliens, E. lucius, C. a. gibelio, T. tinca, A. brama were caught in Lake Simenit. The taxonomic characteristics are presented in the data of this study and in the references. The abbreviations using for the body ratios and meristic characteristics of fish caught in Lake Simenit are given below. 487

4 S. Uğurlu ve N. Polat T.L. : Total Length S.L. : Standart Length B.D. : Body Depth A.L. : Anal Fin Lenght D.L. : Dorsal Fin Lenght H.D. : Head Depth H.L. : Head Lenght H.W. : Head Width Sn.L. : Snout Lenght D : Dorsal Fin A : Anal Fin P : Pectoral Fin V : Ventral Fin L.lat. : Lateral line scales L.tran. : Line transversal scales C.P.L. : Caudal Peduncle Length C.P.D. : Caudal Peduncle Depth E.D. : Eye Diameter B. L. : Barbel Lenght I.D. : Interorbital Distance G.R. : Gill Raker P.T. : Pharyngeal Teeth Sq. : The number of scales on a line between the back of the head and the begining of the caudal fin in the fish without lateral line. Familia: Mugilidae Mugil cephalus Linnaeus, 1758 SL/BD : SL/HL : HL/ED : HL/ID : ID/ED : HW/HD : CPL/CPD : D 1 : IV D 2 : I 7-9 V : I 5 A : III 8 P : II 15 Sq : The general body shape of M. cephalus is shown in Figure 2. Head is broad and flattened. Eyes are with conspicuous adipose eyelid. There are two pyloric caeca, not equal in size. Lateral line is absent. Back is grey-white. There are 7-8 dark coloured, horizontal stripes on lateral sides. Ventral surface is brightly silvery-white. Figure 2. View from the left side of Mugil cephalus 488

5 An Investigation on Fish Fauna in Lake Simenit (Terme-SAMSUN) Liza saliens (Risso, 1810) SL/BD : SL/HL : HL/ED : HL/ID : ID/ED : HW/HD : CPL/CPD : D 1 : IV D 2 : II 7 V : I 5 A : III 8-9 P : II Sq : Body shape is cylindrical anteriorally, becoming a little laterally compressed toward the posterior (Figure 3.). Adipose eyelid is rudimentary. No obvious lateral line. In generally, 7-9 number pyloric caeca is formed two groups in different lengths from dorsal to ventral. The back of leaping grey mullet is brown-grey. Side scales with dark centers that give the appearance of dark longitudional stripes. The belly is a bright silvery-white colour. Figure 3. View from the left side of Liza saliens Familia: Esocidae Esox lucius Linnaeus, 1758 SL/BD : SL/HL : HL/ED : HL/ID : ID/ED : D : VI-VIII V : II 9-10 A : III 8 P : VI-VIII L. lat. : L.tran. :13-17/15-16 Body which is fusiform is sticky; long slender and serpentine (Figure 4.). Mouth is large; horizontal maxillary is usually reaching at least to midpupil. Lateral line is sometimes having intervals in juvenils. The dorsal and the anal fins are convex and near to caudal fin. Back is predominantly dark green to olive-green, to almost brown, lighter on lower sides. Underside is cream to milk-white. 489

6 S. Uğurlu ve N. Polat Figure 4. View from the left side of Esox lucius Familia: Cyprinidae Carasius auratus gibelio (Bloch, 1783) SL/BD : SL/HL : HL/ED : HL/ID : ID/ED : D : IV V : II 7-9 A : III 6-7 P : I L. lat. : L.tran. :13-17/15-16 GR : PT: 4-4 Body is stout, thickset, compressed laterally (Figure 5.). Mouth is small in terminal position, horse-shoe shaped and without barbels. The last unbranched rays of dorsal and anal fins are ossified and the rear edges are modified to form a characteristics serrate spine. Overall colouration is variable, from olive-green through gold to creamy white. Figure 5. View from the left side of Carassius auratus gibelio Tinca tinca (Linnaeus, 1758) SL/BD : SL/HL : HL/ED : HL/ID : ID/ED : ED/BL : CPL /CPD : D : IV 9 V : II 9-10 A : III-IV 7-8 P : I PT: 5-5 L. lat. : L.tran. : 28-33/20-26 GR : The general body shape of T. tinca is shown in Figure 6. Head is triangular. Mouth is terminal position, small in size with thick lips and a pair of well-developed barbels, one at each corner of the mouth. The dorsal and anal fins rounded the caudal peduncle characteristically 490

7 An Investigation on Fish Fauna in Lake Simenit (Terme-SAMSUN) deep and short. Overall colouration is olive-green, at times dark green or almost black, with golden reflections on the ventral surface. Figure 6. View from the left side of Tinca tinca Abramis brama (Linnaeus, 1758) SL/BD : SL/HL : HL/ED : HL/ID : ID/ED : D : III-IV 9-11 V : II 7-8 A : III P : I L. lat. : L.tran. :13-16/7-8 GR : PT: 5-5 Body is thick and laterally compressed (Figure 7.). Mouth terminal, horse-shoe shaped and without barbels. Lateral line is clearly curved to abdomen. The rear edges of the dorsal and anal fins are recessed. There are carinate with scales between the ventral and anal fins. The back is dark grey-greenish. The colour at back lightens toward laterals. The ventral surface is briantlly silvery coloured. Figure 7. View from the left side of Abramis brama 4. Results Morphologies of the fish in Lake Simenit examined in this study. The results about the metric and meristic characteristics were discussed by comparing them with those obtained from previous studies. 491

8 S. Uğurlu ve N. Polat The head length of M. cephalus is equal to body depth according to Geldiay and Balık [11]. However, the head length was found to be greater than the body depth in our samples. Minimum and maximum limits belonging to the meristic characteristics of M. cephalus are almost similar to a lot of investigations [3, 5, 11, 15-20]. But the values of Sq. was higher than its recorded in literature. There were not recorded any unbranched ray in the pectoral fins [11, 15, 17,19, 20], we had found two unbranched rays. Dorsal scales in our samples belonging to Mugilidae having canals between 2 and 5, equivalent in key to identification was determined as L. saliens. The numbers of the unbranched rays in the first dorsal and the numbers of the branched and unbranched rays in the anal and ventral fins were in agrement the other studies [5, 11, 15, 17, 19, 20]. The second dorsal fin was recorded to have 8 (9) branched rays and 1 unbranched ray by lots of researchers [5, 11, 15, 17, 19, 20]. But we determined 7 branched and 2 unbranched rays in the second dorsal fin. The numbers of branched and unbranched rays in the pectoral fins are different from the results of other authors. In addition two unbranched rays were present pectoral fins. Moreover, lateral line scales had counted as by Slastenenko [5], Geldiay and Balık [11], Balık et al. [15], Tekelioğlu [19]. The morphometric characteristics were not in perfect agrement with L. saliens by means numbers of branched and unbranched rays in the second dorsal and pectoral fins, values of Sq. and morphological structure of the caudal fin and triangle shaped piece of skin at base of pectoral fins. Its characteristics are more similar with M. abu by means of the numbers of branched and unbranched rays in the first dorsal, second dorsal, anal pectoral, ventral fins and values of Sq. and ratio of S.L/B.D. in accordance with Geldiay and Balık [11], Balık et al. [15]. However, the caudal fin is more recessed, morphological structure of the caudal peduncle is more slender, body is not more laterally compressed. We concluded that, more samples must be studied to make a true decision about the taxon that present samples belong to. In taxonomical researches concerned with E. lucius, metric characteristics were not mentioned. Minimum and maximum limits of the meristic characteristics of E. lucius resemble results of other researchers [3, 5, 11, 16, 20, 21]. Since no research presenting the body ratios of C. a. gibelio, no comparison can be done. There are some other studies [5, 12, 21] about the meristic characteristics of C. a. gibelio which agrement with the values of our samples. S.L/B.D. of T. tinca is in accordance with Geldiay and Balık [11]. However, the caudal peduncle lenght was found to be more than the caudal peduncle depth in our samples. Ratio of E.D./Bar. L. is included with given result by Slastenenko [5]. Minimum and maximum limits belonging to the meristic characteristics of T. tinca are in accordance with recorded literature [5, 11, 12, 20, 21, 22]. Gill rakers on the first arch were noted as by Slastenenko [5], Geldiay and Balık [11], by Özuluğ [21]. The body ratios of A. brama are similar to a few studies [5, 11, 23]. However, the head lenght of A. brama is smaller than the body depth in mentioned studies, the head lenght of A. brama is bigger than the body depth in this study. Minimum and maximum limits belonging to 492

9 An Investigation on Fish Fauna in Lake Simenit (Terme-SAMSUN) the meristic characteristics of A. brama are almost the same as the previous researches [5, 11, 12, 20]. 5. Conclusions and Suggestions Coastal lagoons containing both some freshwater fish and some marine fish in certain periods are important in point of fishery. Total sampling from the investigation area has all kind of lagoon characteristics was composed of 1.36% M. saliens, 4.45% M. cephalus, 10.95% E. lucius, 16.09% C. a. gibelio, % T. tinca, 36.64% A. brama. The most dominant fish species were T. tinca and A. brama. Population of M. saliens and M. cephalus are under pressure of overfishing due to their economic importance and the potential in reproductive migration. Also E. lucius and C. a. gibelio have been exremely and unconsciously fishing. In addition to overfishing, this system is degenerating rapidly due to pollution, and agricultural activities. An urgently solution should be brought for this situation. Lake Simenit was not studied before. Therefore, determination of fish fauna inhabiting Lake Simenit is important in terms of the composition of the inventory of freshwater fishes in Turkey. This investigation is the first study ichthyofauna of Lake Simenit is determined. References 1. N. Meriç, Fishes Encountered In Küçükçekmece Lake, İstanbul, İstanbul Üniv. Fen Fak. Mec. B, 51, 33-39, Anonim, Karadeniz ve Marmara Kıyılarında Deniz Ürünleri Yetiştiriciliğine Uygun Olabilecek Alanlar, Tarım Orman ve Köyişleri Bakanlığı, Proje ve Uygulama Müdürlüğü, Debçağ 95/G No lu Proje Desteğinde TÜBİTAK Matbaası, 37 s, S. Balık, Türkiye nin Akdeniz Bölgesi İçsu Balıkları Üzerinde Sistematik ve Zoocoğrafik Araştırmalar, Doğa Tu Zooloji, D, 12, 2, , S. Balık and M. R. Ustaoğlu, Türkiye Tatlısu Balıklarını Tanımlama Esasları, No: 97, Ege Üniversitesi, Fen Fakültesi Kitaplar Serisi, Bornova-İzmir, 58 s, E. Slastenenko Karadeniz Havzası Balıkları, Et ve Balık Kurumu Umum Müdürlüğü Yayınlarından, İstanbul, 711 s, M. Blanc, P. Banarescu, J.-L. Gaudet and J.-C. Hureau, European Inland Water Fish, A multilingual Catalogue, FAO, Fishing News (Books) Ltd. London, England, 187 p, W. B. Scott and E. J. Crossman, Freshwater Fishes Of Canada, Bulletin 184, Ottawa, Fisheries Research Board of Canada, 966 p, M. Kuru, Dicle-Fırat, Kura-Aras, Van Gölü ve Karadeniz Havzası Tatlısularında Yaşayan Balıkların (Pisces) Sistematik ve Zoocoğrafik Yönden İncelenmesi, Doçentlik Tezi (Yayınlanmamış), Atatürk Üniversitesi, Erzurum, 183 s, M. Kuru, Key to The Inland Water Fishes of Turkey, Part I, II, III. Hacettepe Bulletin of Natural Sciences and Engineering, 9, , M. Kuru, Türkiye Tatlısu Balıkları Katoloğu, Hacettepe Üniversitesi, Fen Fakültesi Yayınları Yardımcı Ders Kitapları Dizisi, 12, 1, 1, Beytepe, Hacettepe Üniversitesi Fen Fakültesi Basımevi, 73 s,

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