Vol.6 – 2000 – No.3 – Journal of the Black Sea / Mediterranean Environment

LARVAL REARING OF FLOUNDER, PLEURONECTES FLESUS LUSCUS, UNDER LABORATORY CONDITIONS

Larval rearing of flounder, Pleuronectes flesus luscus, under laboratory conditions

Temel Şahin

Central Fisheries Research Institute, Trabzon,TURKEY

Abstract

To establish a seed production technique for flounder Pleuronectes flesus luscus the eggs and larvae were observed under artificial rearing conditions. Larvae were obtained from eggs spawned artificially by tank-held broodstock. The egg fertilization rate varied from 35.3 to 59.2%. The fertilized eggs were approximately 1.15 mm in diameter, spherical, and without oil globule. From initial length of 2.7-3.1 mm on day 0, larvae grew to 10.4-14.0 mm on day 60. The feeding regime consisted of Nannochloropsis, Brachionus, Artemia, and granule feed. With this regime, survival rate were 9.6% at day 60. Larval mortalities considerably increased within two days after hatching and during later part of the larval rearing period between day 8 and day 12 and between day 35 and day 40. The present study demonstrates that adult flounder can be obtained from wild and broodstock management and artificial spawning in captivity, and larval rearing can be achieved successfully.

Keywords: Flounder, Pleuronectes flesus luscus, survival rate, Black Sea, larval rearing, mortality

DISTRIBUTION OF SEAWATER AND RIVERINE SUSPENDED MATTER IN COASTAL WATERS OF TRABZON

Distribution of seawater and riverine suspended matter in coastal waters of Trabzon

Coskun Erüz, Ercan Köse, Filiz Özer, Nüket Sivri, Muzaffer Feyzioglu

Karadeniz Technical University, Faculty of Marine Sciences 61530 Çamburnu, Trabzon, TURKEY

Abstract

There are several small rivers along the coast from Trabzon to Rize. The region is most rainy area of the Southern Black Sea. Therefore, in this area erosion rate about 90%. As a result of this, the rivers along the Black Sea coast transports large amount of sedimentary solid matters to the sea. In this work, 3 rivers and 1 creek runoffs to the Black Sea are studied. Transportation of suspended matter and its concentration were investigated in rivers and seawater. As it was expected, river in suspended matter concentration is high at spring and autumn. However, suspended matters are originated from marine organism and re-suspended sediments. In sea, coastal waters suspended matter concentrations are higher than open sea concentration and max. concentrations were found at near the river mouths.

Keywords: Black Sea, suspended matter, river effect, coastal waters

INVESTIGATION OF HIGH MORTALITIES IN EYED EGGS ANC FRY OF RAINBOW TROUT (ONCORHYNCHUS MYKISS WALBAUM) AND BROOK TROUT (SALMO TRUTTA)

Investigation of high mortalities in eyed eggs anc fry of rainbow trout (Oncorhynchus mykiss Walbaum) and brook trout (Salmo trutta)

Seyit Aydın

Çanakkale Onsekiz Mart University, Faculty of Sea Products, Karacaören, 17100 Çanakkale, TURKEY

Abstract

This work was conducted to investigate high mortalities of eyed-eggs and fry in trout hatcheries during the winter seasons of 1994-1996. Low water temperature (0-6°C), clays covering eggs, directly sun-light and mechanically made faults were observed as the reasons of mortality in brook trout (Salmo trutta) eyed-eggs and fry In one of the hatcheries. Reddening and haemorrhages around eyes of eggs, became hard in yolk-sac of fry. Vibrio parahaemolyticus infections were present in rainbow trout eyed-eggs (Oncorhynchus mykiss Walbaum) in the other hatcheries. Infections caused reddening and haemorrhages around eyes of eggs. Bacterial isolates were identified in each hatchery, and tested to determine sensitivity against to 12 chemotherapeutants. Also, pathogenicity of two isolates were examined using healthy rainbow trout fry. In a therapeutic experiment baths with chloramine-T and norfloxacin controlled the natural V. parahaemolyticus infections.

Keywords: Fish, disease, trout, Vibrio parahaemolyticus, environmental factor

ORCHESTIA CAVIMANA HELLER, 1865 (AMPHIPODA, TALITRIDAE) IN THE TURKISH BLACK SEA FAUNA

Orchestia cavimana Heller, 1865 (Amphipoda, Talitridae) in the Turkish Black Sea fauna

Mehmet Akbulut, Murat Sezgin

Ondokuz Mayis University, Sinop Fisheries Faculty, Division of Basic Sciences, 57000 Sinop, TURKEY

Abstract

This study deals with 1 amphipod species (Orchestra cavimana Heller, 1865) sampled at Sinop Peninsula coasts (0-0,5 m.) at the mouth of Sarıkum lagoon lake (1-2m) 45 species of marine crustacea Amphipoda have been identified in Black Sea coast of Turkey. However, Orchestia cavimana Heller, 1865 is a new species for the Turkish Black Sea coastal waters.

Keywords: Orchestia cavimana, Talitridae, crustaceae, amphipoda, Turkish Black Sea

HEAVY METAL CONCENTRATIONS IN THE SEA SNAIL RAPANA VENOSA (VALENCIENNES, 1846) FROM SINOP COASTS OF THE BLACK SEA

Heavy metal concentrations in the Sea Snail Rapana venosa (Valenciennes, 1846) from Sinop Coasts of the Black Sea

Levent Bat, Gamze Gönlügür, Müberra Andaç, Meral Öztürk, Mehmet Öztürk

University of Ondokuz Mayis, Sinop Fisheries Faculty, Department of Basic Sciences, 57000 Sinop, TURKEY
University of Ondokuz Mayis, Faculty of Science-Arts, Department of Chemistry, 55139 Samsun, TURKEY
Unvversity of Celal Bayar, Faculty of Science-Arts, Department of Biology, Manisa, TURKEY

Abstract

The concentrations of copper, zinc, iron, lead, nickel, manganese and cadmium in the living tissue of the sea snail Rapana venosa (Valenciennes, 1846) from the Sinop coasts of the Black Sea have been measured by atomic absorption spectrophotometer for monitoring metal pollution in the coastal water. A statistically significant difference in the concentrations of all metals was observed among three sampling stations. The results were compared to those of several bivalves and gastropods documented previous studies and discussed.

Keywords: Rapana venosa, heavy metal

OIL POLLUTION IN SEA WATER OF IZMIT BAY FOLLOWING THE EARTHQUAKE (17 AUG 1999)

Oil pollution in sea water of Izmit Bay following the earthquake (17 Aug 1999)

Kasım Cemal Güven, Selma Ünlü

University of Istanbul, Institute of Marine Sciences and Management, Vefa, 344470, Istanbul, TURKEY

Abstract

Oil pollution in Izmit Bay was investigated after the fire of Tüpraş refinery that followed the earthquake in 17 Aug 1999. The highest oil pollution was found in Ereğli on surface water (covered wholly by oil) and in Ulaşlı as 179.2 mg/L in 24-27 Aug 1999 and fell to 425 µg/L in 15-19 Aug 2000. The maximum oil level in surface water in eastern part as 53.2-µg/ L, the central part as 1688 µg/L, in the western part as 463.6 µg/L and one year later it was changed as 10.40 µg/L, 13.68 µg/L and 12.98 µg/l, respectively. The determination of oil origin was made by the fingerprinting analysis method and found that its origin was Tüpraş refinery accident. The results of UVF and GC/MS and fingerprinting analyses are reported in this paper.

Keywords: Sea water, sediment, oil pollution, Izmit Bay

ABUNDANCE AND DISTRIBUTION OF ZOOPLANKTON IN COASTALAREA OF GOKCEADA ISLAND (NORTHERN AEGEAN SEA)

Abundance and distribution of zooplankton in coastal area of Gökçeada Island (Northern Aegean Sea)

Ahmet Nuri Tarkan

University of Istanbul, Faculty of Aquatic Products, Department of Marine Biology, Ordu Caddesi, No. 200, Laleli 34470 Istanbul, TURKEY

Abstract

This study was carried out in order to determine population of zooplankton in the coastal waters of Gökçeada. At the 10 stations of those depths ranging from 20 in to 30 in, the measurements of temperature, salinity and oxygen were made, and zooplankton samples were collected vertically and horizontally using plankton nets. In the neritic waters of the island, the effects of the Black Sea waters through Dardanelles were observed and zooplankton species of the Black Sea found. From laboratory examinations of samples, it was determined that the most important group of zooplankton was copepods. The number of Mnemiopsis leidyi, ctenophor, increased excessively during the periods of summer and autumn. Larger copepod species, such as Centropages typicus, Calanus helgolandicus, Ctenoealanus vanus, Anornalocera patersoni, appeared during winter and spring periods; however, Acartia clausi, which is considered as a indicator of polluted waters, was found to be abundant at every station all around the year. Relatively smaller species such as Corycella rostrata, Oithona helgolandica, Euterpina acutifrons were determined in smaller numbers at most stations. Cladocers were observed at every period: of them, Penilia avirostris was found to be the most observed species. In the samples collected from 40 stations during the year, 51 species were determined.

Keywords: Aegean Sea, zooplankton, composition, abundance