The invasion of Mont-Saint-Michel Bay salt marshes (France) by a grass species (Elymus athericus) has led to important changes in vegetation cover, which is likely to modify the habitat for many invertebrates. Some of them constitute the main food items for several fish species, such as young sea bass (Dicentrarchus labrax) and sand goby (Pomatoschistus minutus), that feed in salt marsh creeks ...

Cascading trophic interactions are often defined as the indirect effects of a predator on primary producers through the effect of the predator on herbivores. These effects can be both direct through removal of herbivores [density-mediated indirect interactions (DMIIs)] or indirect through changes in the behavior of the herbivores [trait-mediated indirect interactions (TMIIs)]. How the relative ...

Acoustic communication is essential to survival for many fish species, however it is often understudied. This thesis investigates two areas of acoustic communication in the round goby (Neogobius melanostomus). These fish have no accessory hearing structures, and theory would predict they would be unable to localize sound sources, however it has been shown that round gobies can localize conspeci...

Differences in boldness are common between populations or between related species and are discussed as part of individual coping style, personality, or behavioral syndrome. Boldness has been found to be dependent on experience, social, and environmental contexts. The major aim of the present study was to establish an experimental environment that would allow analyzing the risk-taking behavior o...

Length-weight relationships (LWRs) are useful for calculating weight based on measurements of length. Here we provide LWRs 17 species fish from the rivers Vltava and Elbe in Czech Republic, Central Europe. The samples were collected by electrofishing May 2016 to August 2019. There far fewer riverine than lotic fish. All significant with r2 values ranging 0.99 European barbel (Barbus barbus) 0.9...

The ecological impact of invasive species is likely to be modulated by human-induced alterations in habitats, which represents another driver biodiversity loss. We tested the effect soundscape degradation on predation round goby Neogobius melanostomus, one Europe’s “worst species”. For this, we compared relationship between per capita rate and prey density (i.e., functional response) presence o...

Seasonal vanation in harbour seal diet in the south-western North Sea was investigated from faeces collected monthly, over a 2 yr period, from a high-water haulout site in the Wash on the east coast of England. A total of 12444 fish otoliths from 31 species was recovered from 708 faeces; otolith measurements were corrected for partial digestion and used to estimate the proportion, by weight, of...

Non-indigenous species (NIS) can impact marine biodiversity and ecosystem structure and function. Once introduced into a new region, secondary dispersal is limited by the physiology of the organism in relation to the ambient environment and by complex interactions between a suite of ecological factors such as presence of predators, competitors, and parasites. Early prediction of dispersal poten...

Sexual selection has given rise, in several taxa, to intrasexual variation in male phenotype. While evolutionary studies have provided explanations of the adaptive function of this dramatic male phenotypic diversity, the proximate control of its expression has still to be completely understood. Several observations, primarily from sex-changing species, indicated a major role of social interacti...