Ecological values of intermittent rivers for terrestrial vertebrate fauna

• Published in: The Science of the total environment Vol. 806; no. Pt 4; p. 151308
• Main Authors: Sánchez-Montoya, María Mar, Gómez, Rosa, Calvo, Jose F., Bartonička, Tomáš, Datry, Thibault, Paril, Petr
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.02.2022; Elsevier
• Subjects: Animals; Biodiversity; cameras; climate change; Dry river channels; Ecological function; ecological value; Ecosystem; environment; Environmental Monitoring; Environmental Sciences; fauna; Flow intermittence; Freshwater ecosystems; geomorphology; Humans; Rivers; species richness; Vertebrates; Wildlife conservation; wildlife management; Ecological function; Dry river channels; Wildlife conservation; Freshwater ecosystems; Biodiversity; Flow intermittence
• ISSN: 0048-9697; 1879-1026; 1879-1026
• DOI: 10.1016/j.scitotenv.2021.151308

Rivers are generally considered critical habitats for biodiversity; however, this often ignores the fact that many rivers may run dry and support terrestrial as well as aquatic fauna. Here, we investigated the ecological value of intermittent rivers for terrestrial vertebrates by installing camera traps along rivers subject to varying dry periods in two contrasting European climatic zones. We then analysed i) species presence and behaviours (as a proxy of ecological functions) on perennial and intermittent streams; ii) environmental (hydrological and geomorphological) and anthropogenic factors affecting the frequency of occurrence and number of species recorded; and iii) the importance of hydrological factors as regards ecological functioning. In both study areas, we recorded a higher number of species and individuals along intermittent streams than perennial streams, with highest values in intermittent reaches exhibiting shorter dry periods. Both abundance and species richness were strongly affected by hydrological factors in both study areas, including not only the occurrence but also the duration of the dry period. Dry channels played a key role as migration corridors and as a source of food, being used more frequently than riparian habitats when the river ran dry. Our findings indicate that terrestrial vertebrate fauna benefit from dry phases in rivers. Intermittent rivers, supporting a high abundance and diversity of fauna, should be considered as target ecosystems for wildlife conservation. Not doing so will jeopardise urgently needed conservation strategies in the face of accelerating global climate change. [Display omitted] •Intermittent streams exhibited higher abundance and species richness than perennial streams.•Shorter dry periods in intermittent streams boosted abundance and species richness.•Hydrological variables, recreational and grazing uses, and riparian slope were the main factors explaining abundances and species richness.•Dry channels were frequently used, mainly as corridors and as source of food.•Intermittent rivers should be considered target ecosystems for conserving wildlife.