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Globally, freshwaters are the most degraded and threatened of all ecosystems. In northern temperate regions, beaver (Castor spp.) reintroductions are increasingly used as a low-cost and self-sustaining means to restore river corridors. River modifications by beavers can increase availability of suitable habitat for fish, including salmonids. This study investigated the response of a population of brown trout (Salmo trutta) to reintroduced Eurasian beaver (Castor fiber) habitat modifications in northern Scotland. The field site comprised two streams entering a common loch; one modified by beavers, the other unaltered. Electrofishing and PIT telemetry surveys indicated abundance of post-young-of-the-year (post-YOY) trout was higher in the modified stream. Considering juvenile year groups (YOY and post-YOY) combined, abundance and density varied with year and season. In the modified stream, fork length and mass were greater, there was a greater variety of age classes, and mean growth was positive during all seasons. Beavers had profound effects on the local brown trout population that promoted higher abundances of larger size classes. This study provides important insight into the possible future effect of beavers on freshwater ecosystems. Les ecosystemes d'eau douce sont les ecosystemes les plus degrades et menaces sur terre. Dans les regions nordiques temperees, les reintroductions de castors (Castor spp.) sont de plus en plus utilisees comme moyen peu couteux et autosuffisant de restauration de couloirs fluviaux. Les modifications des rivieres par les castors peuvent accroitre la disponibilite d'habitats convenables pour les poissons, dont les salmonides. L'etude se penche sur la reaction d'une population de truites brunes (Salmo trutta) a des modifications de l'habitat par des castors eurasiens (Castor fiber) reintroduits dans le nord de l'Ecosse. Le site d'etude compte deux cours d'eau qui se jettent dans le meme loch, un etant modifie par les castors et l'autre etant intact. Des releves a la peche electrique et de detection telemetrique d'etiquettes passives integrees (PIT) indiquentune plus grande abondance de truites juveniles de plus d'un an dans le cours d'eau modifie que dans le cours d'eau intact. L'examen de juveniles de differents groupes d'age (jeunes de l'annee et de plus d'un an) combines revele que l'abondance et la densite varient selon l'annee et la saison. Dans le cours d'eau modifie, la longueur a la fourche et la masse des poissons sont plus grandes, la diversite des classes d'age est plus importante et le taux de croissance moyen est positif durant toutes les saisons. Les castors ont de profonds effets sur la population locale de truites brunes qui favorisent une plus grande abondance des classes de tailles plus grandes. L'etude fournit d'importants renseignements sur l'effet futur possible des castors sur les ecosystemes d'eau douce. [Traduit par la Redaction], Introduction European rivers have been modified by man for centuries for agriculture (e.g., irrigation) (Moss 2008), domestic and industrial water supply (Rotiroti et al. 2019), generation of mechanical and electrical [...]

Populations of anadromous brown trout, also known as sea trout, have suffered recent marked declines in abundance due to multiple factors, including climate change and human activities. While much is known about their freshwater phase, less is known about the species' marine feeding migrations. This situation is hindering the effective management and conservation of anadromous trout in the marine environment. Using a panel of 95 single nucleotide polymorphism markers we developed a genetic baseline, which demonstrated strong regional structuring of genetic diversity in trout populations around the English Channel and adjacent waters. Extensive baseline testing showed this structuring allowed high‐confidence assignment of known‐origin individuals to region of origin. This study presents new data on the movements of anadromous trout in the English Channel and southern North Sea. Assignment of anadromous trout sampled from 12 marine and estuarine localities highlighted contrasting results for these areas. The majority of these fisheries are composed predominately of stocks local to the sampling location. However, there were multiple cases of long‐distance movements of anadromous trout, with several individuals originating from rivers in northeast England being caught in the English Channel and southern North Sea, in some cases more than 1000 km from their natal region. These results have implications for the management of sea trout in inshore waters around the English Channel and southern North Sea. [ABSTRACT FROM AUTHOR]

This paper examines bilingual children's use of language inside and out of the minority language classroom. A total of 145 children between 8 and 11 years of age, attending 16 bilingual Welsh-English primary schools in North Wales, responded to questionnaires (supplemented by classroom observations) requesting information about their language backgrounds, their use of language at school (inside and out of the classroom) and in the wider community, their self-ratings about their linguistic competence in Welsh and in English and their attitudes towards Welsh and English and towards bilingualism per se. Whilst the results, in general, demonstrated a positive attitude towards bilingualism, there was a clear trend towards favouring the use of English outside the classroom. This pattern was mediated by language experiences and perceived language abilities within the individual. The implications of the findings for language policy and planning in education and in minority situations are discussed. (Contains 14 tables and 3 notes.)

Previous work suggests that juvenile salmon recruitment in rain‐fed rivers is negatively influenced by warm and wet winters and cool springs. We tested whether this is generally applicable to a southern England chalk stream characterized by comparatively stable discharges and temperatures. We found that warm spawning and cool emergence temperatures negatively influenced juvenile recruitment between 2015 and 2020. Together these findings suggest an ability to predict juvenile productivity from water temperature records around spawning and fry emergence, thereby allowing time for management interventions in years of unfavourable temperatures. [ABSTRACT FROM AUTHOR]