HAS THE RECOLONIZATION OF THE PO PLAIN BEGUN? UPDATES REGARDING THE PRESENCE OF THE EURASIAN OTTER (Lutra lutra) IN NORTH-EASTERN ITALY

Widespread in Italy in the early 1900s, the Eurasian otter subsequently underwent a dramatic decline that led to its local extinction in many administrative regions, with the exception of a small residual nucleus in southern Italy. For a few years now, the Austrian and Slovenian populations adjacent to north-eastern Italy have been increasing sharply, leading to a recolonization of the area by the species. During 2020, in Friuli Venezia Giulia, surveys of signs of presence were carried out in 48 grid cells (10 x 10 km) to update information on the species’ local distribution. The following monitoring methods were used: monitoring beneath bridges combined with transects along water courses. 17 grid cells tested positive for the presence of the species, and currently, the otter appears widely distributed in Friuli Venezia Giulia along the main waterways of the Eastern Alps and Prealps, and in some areas overlooking the plain of the Tagliamento and the transborder Isonzo-Soča basin, both included in the Po plain. These constitute the first observations of the species for more than 50 years. Compared to previous studies, 13 new grid cells involving the presence of otters were identified, including in lowland areas, suggesting a progressive expansion from the mountain ranges towards the Po-Venetian Plain. This represents, a spur to expand research and implement new studies to improve levels of knowledge about and the consequent protection of the species. Finally, the integration of transects along riverbanks to monitoring beneath bridges, allowed us both to collect numerous observation and to compare our results with previous studies

Buccal swabs for long-term DNA storage in conservation genetics of fish: One-and-a-half-year analysis timeframe

Conservation genetic research is essential for the management and recovery of endangered taxa. However, the invasive collection of biological material for DNA analysis is controversial. From an ethical perspective, non-destructive sampling methods leave the aquatic specimen alive and less invasive procedures minimize stress on the animals. DNA can be obtained from fish using minimally invasive techniques such as buccal swabs. Here we evaluated the performance of buccal swabs for long-term storage of DNA obtained from brown trout (Salmo trutta). The buccal swabs were stored at room temperature and cut into pieces, one part of which was used for extraction of an aliquot and the others were stored as a “biobank” of biological material. The elapsed time from sampling to molecular analysis was one and half year. The amplification of three different DNA targets was tested to assess the effectiveness of the extraction: mitochondrial DNA (the D-LOOP region), nuclear DNA (the LDH gene) and microsatellite DNA at multiple loci. The results showed high quantification (mean value: 281.84±72.4 ng/μL), indicating that DNA could be effectively extracted from the buccal swabs. Our study results suggest that buccal swabs for long-term storage of DNA at room temperature are promising for use in field conservation studies

The gut microbiota of farmed and wild brook trout (Salvelinus fontinalis): evaluation of feed-related differences using 16S rRNA gene metabarcoding

The gut microbiota has become a topic of increasing importance in various fields, including aquaculture. Several fish species have been the subject of investigations concerning the intestinal microbiota, comparing different variables including the intestine portions, the environment and diet. In this study, the microbiota of farmed and wild brook trout (Salvelinus fontinalis) was analysed, considering separately wall and content of the medial portion of the intestine. A total of 66 fish (age class 2+) were sampled, of which 46 wild and 20 farmed brook trout, along two different years. Microbiota data were obtained using a 16S metabarcoding approach by analysing the V3-V4 hypervariable regions of the 16S rRNA. Data showed that the core microbiota of these species is represented by Proteobacteria (Alpha- and Gammaproteobacteria), Actinobacteria, Firmicutes (Bacilli and Clostridia) and, only for farmed animals, Fusobacteria. The latter taxon is likely related to the fishmeal-based diet administered to farmed brook trout. Indeed, alpha and beta diversity analysis showed differences between wild and farmed fish. Finally, statistically significant differences in the microbiota composition were observed between intestinal wall and content in wild fish, while no differences were detected in reared animals

Le ossa faringee inferiori della principali specie di Cyprinidae (Osteichthyes. Cypriniformes) nei fiumi del Friuli Venezia Giulia

Riassunto \u2013 Le ossa faringee rappresentano importanti caratteri per la determinazione sistematica della Familia Cyprinidae, per questo motivo sono state analizzate le ossa faringee di 12 specie, attualmente presenti nel Friuli Venezia Giulia. Pi\uf9 in particolare sono state studiate le dipendenze fra alcune variabili relative a queste strutture e la lunghezza standard degli esemplari appartenenti a ciascuna delle specie in esame, facendo ricorso a regressioni lineari modello I e regressioni LMS. In tal modo \ue8 possibile ricostruire la dieta di uccelli ittiofagi, tra cui Phalacrocorax carbo sinensis, il cui impatto sulle comunit\ue0 ittiche, negli ultimi anni, \ue8 considerato molto pesante. Infatti, la presenza nei boli alimentari delle ossa faringee consente di risalire alla specie ed alla taglia degli esemplari predati

Barbus plebejus dans le bassin du fleuve Isonzo (Italie du Nord-Est).Notes pr\ue9liminaires

Actes de la Table Ronde Internationale Barbus II,, Li\ue8ge 6-8 juillet 199

La pernice bianca Lagopus mutus helveticus (Thienemann, 1829) nel Parco Naturale delle Prealpi Giulie: stime della distribuzione e della consistenza della popolazione

Abstract - In this study we report the results relevant to monitoring of ptarmigans Lagopus mutus helveticus (Thienemann, 1829) in the Julian Prealps Natural Park. The data we have collected have allowed us to establish their distribution, evaluate the extent of their presence and locate the areas whitin the Park which have the most significant role for conservation purposes. We also report some environmental information about the locations selected by ptarmigans. The species is present in the eastern part of the area, though unevenly; we estimate the presence of 16 (11-18) territorial males in spring; in our study area the density of territorial males was 1,83/Km2. We did not spot any territorial males below 1900 metres a.s.l.. A suitability model was generated using distribution data, in order to develop a potential distribution of suitable area for the species within the Park. The eastern portion of the protected area proves to be more relevant to the conservation of the species