The migratory behaviour of Atlantic salmon kelts is poorly understood. Due to the Atlantic salmon's considerable socio‐economic and ecological importance, their precipitous population abundance declines, and the population resilience potential of salmon kelts, addressing these knowledge gaps is important. In this study, directional swimming behaviours and position choice were quantified for the swimming trajectories of 48 acou...

Freshwater mussels in the order Unionida are a highly endangered taxon of ecosystem engineers with a variety of conservation and reintroduction efforts around the world attempting to increase wild populations. The unionid lifecycle involves a parasitic larval life-stage (glochidia), primarily adapted for dispersal rather than growth. Little is known about the behavioural effects of the glochidia on their host fish. We investig...

Migration is critical for life‐cycle completion in diadromous fish species. River connectivity is vital in facilitating these large‐scale movement events, but the extent of present‐day river fragmentation can interfere with these migrations. Fish passage solutions (FPSs) are commonly implemented with the aim of improving river connectivity. In our study, we investigated the performance of two types of FPSs, spill regimes and c...

The European eel is critically endangered due to heavy impact of anthropogenic factors, such as habitat fragmentation, overexploitation and climate change. During downstream migration, silver eels may encounter hydropower plants, which often result in delay or mortality from impingement on trash-racks or turbine passage. These problems can be mitigated with downstream passage solutions, such as angled racks that guide downstre...

The global population of European eel ( Anguilla anguilla ) is rapidly declining, and migration barriers in rivers are believed to be one of several key causes. While progress has been made in the development of bypass solutions, they are often constructed based on a limited knowledge of swimming behaviour. A bypass close to the stream bed is often recommended at fish passage facilities to accommodate downstream eel migration....

The establishment and proliferation of non-native fish species can have a range of effects within the local ecosystem, including alteration of food webs, nutrient cycling, pathogen dynamics and predation, sometimes also resulting in changed behavior and distribution of native fish species. Knowledge about movements and activity patterns is important to understand the dynamics of non-native animals in their new environment. The...

Known as the “king of fishes,” the Atlantic salmon ( Salmo salar , Salmonidae) is an iconic freshwater species whose contribution to human well‐being has long been recognized, as have widespread declines in its abundance, partly due to river regulation. To understand how salmon conservation has been addressed within the ecosystem services (ES) framework, we synthesized the peer‐reviewed literature on ES provided by salmon in r...

The European eel Anguilla anguilla Linnaeus 1758 is critically endangered with recruitment estimated at 5–10% of historical levels. Enhancing survival of recruits is pivotal for conservation, and restoration should consider habitat choice of elvers ascending river systems. We experimentally show that newly ascended elvers choose small pebble habitat over finer and larger substrates, regardless of the presence or absence of pis...