| Abstract | In contrast to old-growth forests, early-successional stands remain understudied despite potentially harbouring species of
conservation interest. With this work, focused on hazel grouse Tetrastes bonasia, a cryptic and indicator species known to
select for close-to-natural forests, we evaluated winter densities, home range, microhabitat selection and diet, combining
DNA-based mark-recapture and metabarcoding from faecal samples. In total, 216 droppings, collected over 2 years along
forest transects in the Italian Alps, were successfully genotyped and 43 individuals were identifed. Density estimates
were similar to values reported by other studies in the Alps with an average of 4.5 and 2.4 individuals/km2
in the frst and
second study year, respectively, and mean home ranges estimated at 0.95 km2
. According to habitat selection models and
eDNA-based diet analysis, hazel grouse selected early-succession secondary-growth forests formed after the abandonment
of traditional agropastoral activities. These forests, mostly composed of hazel Corylus avellana, Norway spruce Picea
abies and Sorbus spp., provided winter food resources and shelter. The diet analysis also highlighted forest arthropods as a
non-negligible source of food. Birds avoided areas subject to intensive browsing by ungulates; small forest roads seasonally
closed to trafc had positive infuence on hazel grouse (i.e. higher abundance of droppings), while roads open to trafc had
no efect. Importantly, despite the high coverage of mature forest habitats of Community Interest (53% of our study area),
droppings were more abundant in non-listed early-succession secondary forests with similar plant composition. Our results
suggest that forest succession after agropastoral abandonment may be benefcial for some forest birds of conservation interest, while acknowledging its negative efects on the previous grassland biodiversity |
| Authors | Scridel D., Tenan S., Brambilla M., Celva R., Forti A., Fracasso I., Volcan G., Dorigatti E., Anderle M., Marchesini A., Crestanello B., Vernesi C., Pedrini P., Partel P. |
| Text | 470020 2022 10.1007/s10342 022 01485 1 Forest succession Tetrastes bonasia eDNA Habitat selection Tetraonid Early succession secondary forests following agropastoral abandonment are key winter habitats for the conservation of a priority bird in the European Alps Scridel D., Tenan S., Brambilla M., Celva R., Forti A., Fracasso I., Volcan G., Dorigatti E., Anderle M., Marchesini A., Crestanello B., Vernesi C., Pedrini P., Partel P. Museo delle Scienze di Trento MUSE , Sezione Zoologia dei Vertebrati, 38123 Trento, Italy Ente Parco Naturale Paneveggio Pale di San Martino, 38054 Primiero San Martino di Castrozza Trento , Italy CNR IRSA National Research Council Water Research Institute, via del Mulino 19, 20861 Brugherio, MB, Italy Institute of Marine Sciences, CNR ISMAR , National Research Council, 30122 Venice, Italy Dipartimento di Scienze e Politiche Ambientali, Universita degli Studi di Milano, 20133 Milan, Italy Institute for Alpine Environment, Eurac Research, Drususallee/Viale Druso 1, 39100 Bolzano/Bozen, Italy Department of Ecology, University of Innsbruck, Sternwartestrasse 15/Technikerstrasse 25, 6020 Innsbruck, Austria Conservation Genetics Unit, Research and Innovation Centre Fondazione Edmund Mach, 38010 S. Michele all Adige Trento , Italy Forest Ecology Unit Research and Innovation Centre Fondazione Edmund Mach, via E. Mach, 1, 38010 San Michele all Adige Trento , Italy Institute for Sustainable Plant Protection IPSP , The National Research Council of Italy CNR , 50019 Sesto Fiorentino, Florence, Italy Faculty of Science and Technology, Free University of Bolzano Bozen, 39100 Bolzano, Italy In contrast to old growth forests, early successional stands remain understudied despite potentially harbouring species of conservation interest. With this work, focused on hazel grouse Tetrastes bonasia, a cryptic and indicator species known to select for close to natural forests, we evaluated winter densities, home range, microhabitat selection and diet, combining DNA based mark recapture and metabarcoding from faecal samples. In total, 216 droppings, collected over 2 years along forest transects in the Italian Alps, were successfully genotyped and 43 individuals were identifed. Density estimates were similar to values reported by other studies in the Alps with an average of 4.5 and 2.4 individuals/km2 in the frst and second study year, respectively, and mean home ranges estimated at 0.95 km2 . According to habitat selection models and eDNA based diet analysis, hazel grouse selected early succession secondary growth forests formed after the abandonment of traditional agropastoral activities. These forests, mostly composed of hazel Corylus avellana, Norway spruce Picea abies and Sorbus spp., provided winter food resources and shelter. The diet analysis also highlighted forest arthropods as a non negligible source of food. Birds avoided areas subject to intensive browsing by ungulates; small forest roads seasonally closed to trafc had positive infuence on hazel grouse i.e. higher abundance of droppings , while roads open to trafc had no efect. Importantly, despite the high coverage of mature forest habitats of Community Interest 53% of our study area , droppings were more abundant in non listed early succession secondary forests with similar plant composition. Our results suggest that forest succession after agropastoral abandonment may be benefcial for some forest birds of conservation interest, while acknowledging its negative efects on the previous grassland biodiversity Published version https //link.springer.com/article/10.1007/s10342 022 01485 1 Scridel ey al EJFR 2022 s10342_022_01485_1.pdf Articolo in rivista Springer. 1612 4669 European journal of forest research Print European journal of forest research Print Eur. j. for. res. Print European journal of forest research. Print Forest research Berlin Print alexismarchesini MARCHESINI ALEXIS davidescridel SCRIDEL DAVIDE simone.tenan TENAN SIMONE simone.aisa AISA SIMONE |
