36 research outputs found
River connectivity reestablished:Effects and implications of six weir removals on brown trout smolt migration
Pike (Esox lucius L.) on the edge: consistent individual movement patterns in transitional waters of the western Baltic
Pike (Esox lucius L.) on the edge: consistent individual movement patterns in transitional waters of the western Baltic
The importance of oil and gas platform foundations for a key commercial fish species, the Atlantic cod
The effect of turbidity and prey fish density on consumption rates of piscivorous Eurasian perch Perca fluviatili
Predator-prey interaction strengths in variable environments constitute a fundamental link to the understanding of aquatic ecosystem responses to environmental change. The present study investigates the effects of visibility conditions and prey fish density on predation rates of visually oriented piscivorous Eurasian perch Perca fluviatilis L. This was done in outdoor mesocosm (16 m2) experiments with clear water and two levels of turbidity (25 and 105 NTU) and two prey fish densities [3.1 and 12.5 roach Rutilus rutilus (L.) individuals m–2]. Perch consumption rates were affected by visibility less than expected, while they were highly affected by increased prey fish density. Perch responded to high prey density in all visibility conditions, indicating that prey density is more crucial for consumption than visibility in turbid lakes