Several hypotheses concerning the dominance of percids under mesotrophic lake conditions were tested in five lakes of intermediate trophic state, situated in northeastern Germany. In contrast to prediction, the fish communities in four lakes were dominated by cyprinids (roach, Rutilus rutilus and bream, Abramis brama), while percids (Eurasian perch, Percafluviatilis) dominated in one lake only....

Biomanipulation by fish removal has been used in many shallow lakes as a method to improve lake water quality. Here, we present and analyse 30 years of chemical and biological data from the shallow and 16 ha large Lake Væng, Denmark, which has been biomanipulated twice with a 20-year interval by removing roach (Rutilus rutilus) and bream (Abramis brama). After both biomanipulations, Lake Væng s...

In a mesocosm study, somatic and otolith growth of common dace (Leuciscus leuciscus) and bream (Abramis brama) differing in body size and body shape were studied in a wave and a no-wave control regime. A low-intensity wave treatment, causing hydrodynamic stress comparable to that resulting from distant ship traffic or moderate wind, caused significant changes in somatic growth and otolith daily...

Optimality theory rests on the assumptions that short-term foraging decisions are driven by variation in environmental quality, and that these decisions have important implications for long-term fitness. These assumptions, however, are rarely tested in a field setting. We linked behavioral foraging decisions in food patches with measures of environmental quality covering larger spatial (resourc...

Partial migration, in which a fraction of a population migrate and the rest remain resident, occurs in an extensive range of species and can have powerful ecological consequences. The question of what drives differences in individual migratory tendency is a contentious one. It has been shown that the timing of partial migration is based upon a trade-off between seasonal fluctuations in predatio...

This study presents concentrations of iron, manganese, zinc, and copper in selected tissues of two fish species: pike (Esox lucius L.) and bream (Abramis brama L.) living in lakes Ińsko and Wisola, Northwestern Poland. The lakes differ in their trophic status. The effect of gender and environmental conditions on metals accumulation was also investigated. Metal analyses were performed using indu...

The brominated flame retardant hexabromocyclododecane (HBCD) was monitored in fish and sediment (from one lake) or suspended particulate matter (SPM; from five rivers) at European freshwater sites to study the effects of reduction measures implemented by HBCD producers and users in recent years. Bream (Abramis brama) were sampled annually between 2007 and 2013 in the rivers Götaälv/SE, Rhône/FR...

Monogeneans, which are mainly fish ectoparasites, use various types of haptoral (posterior) attachment apparatus to secure their attachment onto their hosts. However, it remains unclear how strongly a monogenean can attach onto its host. In the present study, we aimed for the first time to (1) measure pull-off forces required to detach a pair of clamp-bearing monogeneans, Diplozoon paradoxum, f...

The main objectives of study were to determine the concentrations of As and other trace elements (Al, Co, Fe, Ni, Sn, Se) in the muscle, liver, and gills of pikeperch (Sander lucioperca), catfish (Silurus glanis), and pike (Esox lucius), and in the muscle of Prussian carp (Carassius gibelio) and freshwater bream (Abramis brama), to identify relationships between element concentrations and total...