Patterns in helminth community structure can suggest that various processes are acting to shape parasite communities into organised, nonrandom assemblages of species. It is not clear, however, whether a pattern observed in one host population at one time would be observed again at another time, or at the same time in a different but comparable host population. Here, we test the repeatability of...

Environmental pollution by pharmaceuticals is increasingly recognized as a major threat to aquatic ecosystems worldwide. A variety of pharmaceuticals enter waterways by way of treated wastewater effluents and remain biochemically active in aquatic systems. Several ecotoxicological studies have been done, but generally, little is known about the ecological effects of pharmaceuticals. Here we sho...

The population total length (LT) structures and individual growth trajectories for three stream living pike Esox lucius populations were studied for 7 years. All three populations exhibited small variation in both population LT structure and individual growth trajectories over time. These dynamics contrasted to the much more variable population LT structure of perch Perca fluviatilis studied pr...

Humic lakes are abundant in the temperate and cold regions of the Boreal Zone. High levels of water colour and strong thermal stratification of humic lakes limit the potential fish habitats and give a special role to the intraspecific and interspecific interactions. Water colour has different effects on species depending on speciesspecific life-history traits and trophic interactions. Fish spec...

Previous microsatellite analysis showed that two subpopulations of perch (Perca fluviatilis L) exist in Lake Constance. This raises questions of whether (i). Lake Constance was colonized by two populations that diverged in allopatry, or (ii). the two subpopulations diverged in sympatry. Sequence analysis of a 365 bp mtDNA fragment (5'-end of the D-loop) of perch from Lake Constance and adjacent...

Standardized ecotoxicological tests still constitute the fundamental tools when doing riskassessment of aquatic contaminants. These protocols are managed towards minimal mortality in the controls, which is not representative for natural systems where mortality is often high. This methodological bias, generated from assays where mortality in the control group is systematically disregarded, makes...

Conflict arises in fisheries worldwide when piscivorous birds target fish species of commercial value. This paper presents a method for estimating size selectivity functions for piscivores and uses it to compare predation selectivities of Great Cormorants (Phalacrocorax carbo sinensis L. 1758) with that of gill-net fishing on a European perch (Perca fluviatilis L. 1758) population in the Curoni...

In enclosure experiments in the littoral zone of Lake Constance, Germany, juvenile cyprinids showed significantly reduced somatic growth in the shallow eulittoral zone (0 5 m depth) compared to the sublittoral zone (1 6 m depth). Growth was especially reduced in larger and more deep-bodied fish groups, providing evidence that this is due to increased hydrodynamic stress, induced by ship and win...