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Öğe Effect of starvation on the biochemical compositions and respiration rates of ctenophores Mnemiopsis leidyi and Beroe ovata in the Black Sea(Cambridge Univ Press, 2005) Anninsky, BE; Finenko, FA; Abolmasova, GI; Hubareva, ES; Svetlichny, LS; Bat, L; Kideys, ALThe proximate biochemical composition and metabolic rates of ctenophores Mnemiopsis leidyi and Beroe ovata from the Black Sea were examined with respect to starvation conditions. Although organic matter content in B. ovata was two times higher than that of M. leidyi (2.51 +/- 0.53 and 1.4 +/- 0.17 mg g(-1) of wet weight, respectively), these species did not significantly differ in their biochemical composition. In both species protein formed about 80% of the total organic matter, lipids amounted to about 10%. Carbohydrate and amino acids measured separately made up less than 6.5% of the total organic matter. Under experimental starvation (18 days at 16-18 degrees C for B. ovata and 8 days at 12.4 degrees C for M. leidyi), wet weights of both ctenophore species were reduced by 9.4% and 9.3% d(-1), respectively. The rate of organic matter decrease was nearly two times lower than that of wet weight being on average 5.9% d(-1) in M. leidyi and 5.5% d(-1) in B. ovata. There was no trend in percentage of the four major biochemical categories with starvation time. The glycogen content in polysaccharides reached maximum values in freshly collected ctenophores (76.0 +/- 7.9% in B. ovata, and 86.6% in M. leidyi), but it was reduced substantially (34.4 +/- 2.7% in B. ovata and 18.3-28.8% in M. leidyi) with starvation. Monosaccharide content, expressed as a percentage of total carbohydrate, decreased from 39.9% to 13.5% in B. ovata, and from 45.8% to 14.3-23.2% in M. leidyi. The relationship between respiration rate (R) and wet weight (W) of individuals during the starvation can be expressed by power function R = R-1 W-k (r(2)=0.85-0.94; P<0.001) for both ctenophore species. On average, k values were 0.95 and 0.83 in B. ovata and in M. leidyi, respectively. By the end of the starvation, metabolic rate per unit wet weight decreased by 33% in B. ovata and 46% in M. leidyi. Organic matter utilization was almost totally explained by respiration of ctenophores in the experiments and exceeded metabolic requirements of studied species by 11% and 15%, correspondingly. As compared with Mnemiopsis, Beroe has better tolerance to starvation which explains to some extent the success of the species survival during prolonged periods of food shortage in the Black Sea conditions.Öğe Marine Litter Quantification in the Black Sea: A Pilot Assessment(2016) Moncheva, S; Stefanova, K; Krastev, A; Apostolov, A; Bat, L; Sezgin, MVarious programs and organizations (IMO, UNEP, IOC UNESCO, FAO) and recently the EU MSFD recognized marine litter (ML) as an issue of global threat from environmental, economic, human health and safety, and aesthetic aspect. Among the efforts to combat the problem adequate monitoring and application of harmonized methodological approaches for quantification are essential. This research presents the results of a pilot assessment of bottom ML in the Black Sea during the MISIS Project Joint Black Sea Cruise (22-31 August, 2013) along 3 transects in the NW Black Sea. The aim of the present study is a pilot quantitative assessment of bottom.Öğe Population dynamics, ingestion, growth and reproduction rates of the invader Beroe ovata and its impact on plankton community in Sevastopol Bay, the Black Sea(Oxford Univ Press, 2003) Finenko, GA; Romanova, ZA; Abolmasova, GI; Anninsky, BE; Svetlichny, LS; Hubareva, ES; Bat, LThe impact of the introduced ctenophore Beroe ovata on its prey Mnemiopsis leidyi, another invader ctenophore voraciously feeding on mesozooplankton, and consequently on the mesozooplankton community, was evaluated by undertaking both laboratory and field studies in the northern Black Sea. Ingestion and growth rates as well as the gross growth efficiency of B. ovata were estimated from laboratory experiments. The daily ration of ctenophores was related to food abundance within a wide range of prey concentration and never reached saturation. Beroe ovata required high food rations (not less than 20% of body weight per day) for growth. The abundances, biomasses and population structures of these two introduced ctenophore species were also monitored, along with mesozooplankton, in inshore waters of the northern Black Sea (i.e. Sevastopol Bay and adjacent regions) over a period of 3 years (1999-2001) which is after B. ovata's arrival. The annual dynamics of the M. leidyi population were similar for the last 3 years: very low abundances and biomass values were observed during most of the year (unlike the previous years), with a sudden increase in summer-early autumn, but only for about a 2 month period. The B. ovata bloom during the peak M. leidyi biomass resulted in the M. leidyi biomass falling sharply to extremely low values. The predatory impact of M. leidyi on prey zooplanton was found to be reduced during the period of study compared with before.Öğe Respiration rates of Beroe ovata in the Black Sea(Springer Heidelberg, 2004) Svetlichny, LS; Abolmasova, G; Hubareva, ES; Finenko, GA; Bat, L; Kideys, AEMetabolic rates of the ctenophore Beroe ovata within the length range from 0.4 mm (newly hatched larvae) to 60 mm were investigated. At 20degreesC the respiration rates (Q, mug O-2 ind.(-1) h(-1)) of individuals with wet weights (W, mg) less than or greater than 100 mg changed according to the equations Q=0.093W(0.62) and Q=0.016W(0.99), respectively. The weight-specific respiration rate of the juvenile ctenophores with wet body weights of 0.021-100 mg diminished approximately 20-fold (from 0.35 to 0.017 mug O-2 mg(-1) h(-1), respectively), but did not change within the range from 100 to 30,000 mg. The difference in the slope of the regression lines seems to be attributable to the ontogenetic changes in B. ovata metabolism. For the tested temperature range of 10-28degreesC, the mean Q(10) coefficient was equal to 2.17+/-0.5. The basal metabolism of B. ovata narcotised by chloral hydrate was 4.5+/-0.9 times lower than total metabolism. Such a metabolic range is considered to be characteristic of aquatic invertebrates with high levels of locomotory activity.Öğe Seasonal distribution of fish eggs and larvae off sinop (the southern Black Sea) in 1999-2000(Elsevier, 2003) Satilmis, HH; Gordina, AD; Bat, L; Bircan, R; Culha, M; Akbulut, M; Kideys, AEThe seasonal distribution of fish eggs and larvae off Sinop, the central southern Black Sea, was studied by using vertical and horizontal tows at two stations at biweekly intervals between January 1999 and November 2000. Besides basic oceanographic parameters, macro gelatinous was also sampled to evaluate their relation to fish eggs and larvae. Eggs or larvae of a total 23 fish species were present in the samples. Most of the species were found to occur during spring and summer. It is observed that especially anchovy (Engraulis encrasicolus) eggs and larvae were highly abundant during this period. Additionally, beginning from May, the eggs and larvae of species, such as Mullus barbatus, Solea lascaris, Trachurus mediterraneus, Ctenolabrus sp., Blennidae and Gobiidae were represented in samples. In the colder period of the year, early life stages of sprat (Sprattus sprattus) were dominant in ichthyoplankton. According to overall quantitative evaluation, anchovy (87%) had superiority in abundance among egg samples and Gobius sp. (35%) among larvae samples. (C) 2003 Editions scientifiques et medicales Elsevier SAS. All rights reserved.Öğe Summer ichthyoplankton, food supply of fish larvae and impact of invasive ctenophores on the nutrition of fish larvae in the Black Sea during 2000 and 2001(Cambridge Univ Press, 2005) Gordina, AD; Zagorodnyaya, JA; Kideys, AE; Bat, L; Satilmis, HHQualitative composition and abundance of both ichdryoplankton and small forms of zooplankton were evaluated by field studies in the northern (the Crimea near Sevastopol) and Southern (Sinop region and TEEZ) Black Sea during the summers 2000 and 2001. A tendency of increasing the species richness, abundance of fish eggs and larvae as well as zooplankton (which is the food for fish larvae) was observed over a period of Mnemiopsis leidyi and Beroe ovata co-existence. The eggs and larvae of the Mediterranean migrants-bonito and bluefish appeared again in the coastal waters near Sevastopol, which testified to favourable conditions for the spawning and nutrition of these fish species and their larvae. Aborigen copepod Oithona nana was found in the Crimean coastal waters although earlier in the 1990s it had completely vanished. Although rare in the 1990s copepods Centropages ponticus and Paracalanus parvus appeared in inshore waters as well as Pontellids species. Observed increases in species number and abundance of both ichdryoplankton and small zooplankton (: 500 pin), which promoted survival and development of fish larvae, were attributed to reduced predatory impact of Mnemiopsis on prey zooplankton after the arrival of Beroe in the late 1990s. However, the influence of Mnemiopsis continued to be significant during the short period of its peak occurrence in late summer. When this period coincided with the appearance of fish larvae, a negative impact on their survival could be predicted due to a low concentration of food items for larvae feeding.
