Every year millions of migratory birds cross the Alps during their seasonal movements between Europe and Africa. This fascinating phenomenon has been studied since 1995 in several sites of the Trento province, distributed from bottom valleys to mountain passes, during both the pre-breeding and post-breeding seasons. The surveys are in particular focused on phenology, eco-physiology, migratory connectivity and environmental factors that influence the dynamics of the populations in migration.

In this research field, two major projects are ongoing, based on bird ringing and long-term monitoring, especially on migratory Passerines.


It is a national research project started in 1997, included in the European EURING schemes for studying migration through scientific bird ringing, and it is coordinated by the Muse and the National Centre for Bird Ringing of ISPRA. Over the years, 44 bird ringing stations across the whole Italian Alpine region have participated to the project. Two of these stations are in Trentino: Bocca di Caset in Ledro Valley and Passo del Brocon in Tesino.

In these two field stations, every year, from August to October, authorized bird ringers, specialised field assistants, volunteers and aspiring bird ringers collaborate with researchers, interns and thesis students coming from several Italian Universities, all of them coordinated by our Department.

The research activity is combined with educational and demonstration activities aimed at getting students, tourists and curious people familiar with the bird migration phenomenon and the methods used to study it.

Since last year, our Department edits the project website available at this link.


This study uses the analysis of stable isotopes to examine the geographic origin of the migratory birds in Trentino and, more broadly, across the whole Italian Alpine region. This has been the subject of a PhD started in 2013 and now concluded, carried out together with the Food Quality and Nutrition Department – Traceability Unit of the Edmund Mach Foundation (TN).

The ratio of certain stable isotopes (in this study oxigen, carbon, nitrogen and sulfur) varies depending on biogeochemical processes in space and time, that give the earth surface different isotopic profiles in different areas. A specific isotopic profile is fixed in animal tissues through the diet, reflecting the specific isotopic profile of a determined area.

Keratin tissues, like bird feathers, contain information on the isotopic profile of the geographic area where they formed. The ratio reveals ecological connections among breeding, wintering and resting areas specific to each bird analysed. This research has been conducted in particular on Passerines that have been mist-netted within the Progetto Alpi, increasing the knowledge on the migratory ecology that can help the conservation of migratory birds, especially of threatened species.


Recent publications:

  • Franzoi A., Bontempo L., Camin F. and Pedrini P., 2015. Studying birds flyways by ringing and stable isotopes (δ2H): a contribution for the conservation of European birds.10th Conference of the European Ornithologist’s Union, 24-28 August 2015, Badajoz (Spain). Poster.
  • Franzoi A., Pedrini P., Camin Federica. and Bontempo L., 2015. Ecological behaviour of birds in post-breeding migration through the Alps using a multi isotope ratio technique. 10th Conference of the European Ornithologist’s Union, 24-28 August 2015, Badajoz. Poster.
  • Alessandro Franzoi, Luana Bontempo, Paolo Pedrini, Federica Camin, 2016. Geographical origin of birds migrating through Alps: a stable isotope approach (δ2H). The 1 St Isotope Ratio Ms Day, May 9-11, 2016, Fondazione Edmund Mach, San Michele all’Adige (TN). Oral presentation.
  • Franzoi A.,  Bontempo L.,  Pedrini P.,  Camin F., 2016. Trophic ecology of migratory birds as shown by stable isotopes (δ13C, δ15N, δ34S). The 1st Isotope Ratio Ms Day, May 9-11, 2016, Fondazione Edmund Mach, San Michele all’Adige (TN). Poster.