Gastric emptying, clearance rate, feeding periodicity and food consumption of the Black Sea jelly fish, Mnemiopsis leidyi (Agassiz)

59-64The feeding physiology of Mnemiopsis leidyi fed on Artemia salina were investigated under laboratory conditions. Multifactorial experimental designs were used to study the factors affecting gastrovascular emptying in M. leidyi. A high correlation was found between number of prey ingested and digestion time. Modelling of gastric emptying time (GET,h.) of M. leidyi fed on A.salina was attempted to describe the effect of animal size, prey number, container volume and temperature on the digestion time. GET= 3.42- 0.00636 W + 0.0121 pN - 0.155 V - 0.00983 T. The clearance-rate was significantly affected by container volume and the feeding time. Multiple regression was attemped to model clearance rate: CR = 0.366 + 0.377 V - 0.197 H. Studying the feeding periodicity over a 24 h period, it was found that under laboratory condition and with readily available prey, M. leidyi feeds continuously except for the early hours of the day. Under such conditions medium size Mnemiompsis (11.36±0.38 g) consumed between 1286 and 2741 artemia daily. With the models of gastric emptying time (GET) and clearance rate (CR) presented in this study, quantitative assessment of the predatory impact of the ctenophore Mnemiopsis leidyi on the Black Sea ecosystem can be faciliated

Diel feeding periodicity, gastric emptying, and estimated daily food consumption of whelk (<i style="">Rapana venosa)</i> in the south eastern Black Sea (Turkey) marine ecosystem

249-251Gastric emptying, food consumption and feeding periodicity of Rapana venosa were investigated under laboratory conditions and in the field respectively. Gastric emptying was best described by an exponential function, that was independent of meal size and the range of animal size when rapana were fed on fresh mussel. The fresh mussel (0.92-2.19 g) was fully digested by an average of 47 g rapana within the 6-8 hours. No change in feeding intensity was detected over 24 hours suggesting that rapana feed continioussly. Using gastric emptying rates from the laboratory studies, the data obtained from the field was converted to the food consumption estimates and concluded that an average of 50 g rapana in the eastern Black Sea marine ecossystem consume 0.17-0.30 g. mussel in a day, meaning that rapana in the eastern Black Sea marine ecosystem may cause an important predatory impact on the mussel beds

Beyond special circumstances: climate change policy in Turkey 1992–2015

The contours of Turkey's climate policy have remained almost intact over the past two decades. Being an Annex I party without any mitigation commitments, Turkey maintains a peculiar position under UNFCCC. Subsequent to 12years of delay in signing both the Framework Convention and the Kyoto Protocol, Turkey had the highest rate of increase in greenhouse gas emissions among the Annex I countries with 110.4% upsurge in the period 1990 and 2013. Yet with the new climate regime now in place, the country's mitigation pledges fall short of expectations both in terms of realistic projections and its ambition to step up in the post-2020 period. Climate policies in Turkey, an EU candidate and OECD founding member with a growing economy, remain under-investigated. Although the country has a wide range of policies and institutions in place, it shows limited progress in addressing climate change. Based on evidence from the literature, we observe that climate policies operationalize in Turkey insofar as they do not directly confront developmental ambitions, leaving policy diffusion with limited success. To provide a historic overview, we focus on climate policy development, actors, processes, and contemporary trends. Evidence shows that these are highly ridden with the politics of special circumstances: a notion that Turkey employs to refrain from bindings commitments. In order to go beyond special circumstances discourse, we argue the need for a bold policy shift in Turkey, a country subject to adverse impacts of climate change and high-carbon lock-in risk due to development policy preferences.</p