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
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)
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
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
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)
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 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
Reproductive biology of Ruditapes decussatus (Linnaeus,1758) in Çardak Lagoon, Dardanelles Strait
Ahmet Mutlu Gözler, Ahmet Nuri Tarkan
Karadeniz Technical University, Faculty of Aquatic Products, Rize,TURKEY
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 the reproductive period of the carpet clam (Ruditapes decussatus L. 1758). 43.32 % of the examined clams were the females, and 34.38 % were the males and the sex ratio was 1:1,23. Microscopical investigations indicated that the early spawners appeared in March-April. The gonad development started in March and spawning took place between July and October. Histological examinations revealed that gonad development started in March and terminated in October. The period between November and March was the resting stage of clam. The number of ripened individuals made a pike in June. Condition Index results were almost parallel with those of histological examinations. Determinations of temperature, salinity and chlorophyll-a revealed that Ruditapes decussatus spawned at 24˚C temperature and a salinity value between 20-26 ‰.
Keywords: Ruditapes decussatus, reproductive biology Çardak Lagoon, Dardanelles Strait
Coastal aquaculture: Sustainable development, resource use and integrated environmental management
Ibrahim Okumuş
KTU Faculty of Marine Sciences, Department of Fisheries, 61530 Çamburnu, Trabzon, TURKEY
Abstract
With a dramatic expansion over the past two decades, aquaculture has now become a world-wide aqua-industry and kept the global fisheries production increasing despite the levelling off the capture fisheries. Annual production from this new industry now approached to 30 million tonnes, while the captures fisheries almost levelled off around 90 million tonnes. Inland aquaculture still continues to play a significant role, but rapidly developing coastal aquaculture produced 43.1% of aquaculture output in 1997. However, aquaculture is not only a producer of aquatic food but also a consumer competing for infinite resources and rapid development brought some problems as well. Therefore, sustainable development such a. rate to compensate and ultimately supplement the traditional fisheries in new millennium depends on addressing resource allocation and. environmental interactions within the broader framework of integrated environmental management programmes. This article reviews the recent developments in coastal aquaculture and discusses the available resources and constraints limiting the sustainable development. In particular, the way in which coastal aquaculture interact with the environment has been evaluated.
Keywords: Mariculture, developments, constraints, environmental effects, coastal management
Oil pollution in Tuzla Bay after TPAO Tanker accident
Selma Ünlü, Kasim Cemal Güven, Ertugrul Dogan, Erdogan Okus
University of Istanbul, Institute of Marine Sciences and Management, Vefa, 34470, Istanbul, TURKEY
Abstract
The oil pollution was investigated in seawater, sediments and mussels in Tuzla Bay after the TPAO tanker accident. 214.3 ton oil was spilled and 250 ton oil burnt. The pollution level was determined in seawater, sediments and mussels after the accident. The highest pollution was found as 33.2 mg/L in seawater, 423.01µg/g in sediment on the first day after the accident and 2067µg/g in mussels 1 month after the accident. The pollution level decreased during the survey of 14 Feb 1997 to 13 Feb 1998.The origin of oil in seawater, sediments and mussels were identified by using fingerprinting analysis technique.
Keywords: Oil pollution TPAO tanker accident, crude oil, Tuzla Bay