56 research outputs found
Effect of Sub-Lethal Exposure to Ultraviolet Radiation on the Escape Performance of Atlantic Cod Larvae (Gadus morhua)
The amount of ultraviolet (UV) radiation reaching the earth's surface has increased due to depletion of the ozone layer. Several studies have reported that UV radiation reduces survival of fish larvae. However, indirect and sub-lethal impacts of UV radiation on fish behavior have been given little consideration. We observed the escape performance of larval cod (24 dph, SL: 7.6Âą0.2 mm; 29 dph, SL: 8.2Âą0.3 mm) that had been exposed to sub-lethal levels of UV radiation vs. unexposed controls. Two predators were used (in separate experiments): two-spotted goby (Gobiusculus flavescens; a suction predator) and lion's mane jellyfish (Cyanea capillata; a âpassive" ambush predator). Ten cod larvae were observed in the presence of a predator for 20 minutes using a digital video camera. Trials were replicated 4 times for goby and 5 times for jellyfish. Escape rate (total number of escapes/total number of attacks Ă100), escape distance and the number of larvae remaining at the end of the experiment were measured. In the experiment with gobies, in the UV-treated larvae, both escape rate and escape distance (36%, 38Âą7.5 mm respectively) were significantly lower than those of control larvae (75%, 69Âą4.7 mm respectively). There was a significant difference in survival as well (UV: 35%, Control: 63%). No apparent escape response was observed, and survival rate was not significantly different, between treatments (UV: 66%, Control: 74%) in the experiment with jellyfish. We conclude that the effect and impact of exposure to sub-lethal levels of UV radiation on the escape performance of cod larvae depends on the type of predator. Our results also suggest that prediction of UV impacts on fish larvae based only on direct effects are underestimations
Price-Based Unit Commitment Electricity Storage Arbitrage with Piecewise Linear Price-Effects
Effects of predator exposure on baseline and stressâinduced glucocorticoid hormone concentrations in pumpkinseed Lepomis gibbosus
We compared baseline and maximal cortisol concentrations between predator exposure and prey blood samples in pumpkinseed Lepomis gibbosus, captured using a standardised fishing event underneath osprey Pandion haliaetus nests and away from osprey nests. We did not detect differences in cortisol or glucose between sites. These findings suggest that predictable sources of predation risk may not confer stress-related costs in teleosts
Review of mathematical programming applications in water resource management under uncertainty
Parameterisation of numerical models for CO2 storage with regard to storage security during longwall mining operations
Injection techniques for CO2 storage by sorptive linkage to mining waste in abandoned coal mines
First results in the attempt to adept a data mining strategy for distinguishing global, regional and local factors reflecting variation patterns in river water chemistry
Maligner Phylloidestumor der Brust - eine seltene Tumorentität. Fallbericht eines Rezidives
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