This report presents the first complete natal dispersal trajectory of a female Montagu’s Harrier Circus pygargus, tracked in real time from fledging to first breeding using high-resolution continuous Global Positioning System (GPS) telemetry. The bird’s first flight occurred on 26 July 2024, initiating a 31-day post-fledging dependence phase (PFDP), followed by a 23-day pre-migratory phase (PMP), during which it explored areas up to 280.8 km from the nest and eventually settled ca. 190 km away in the Sirente-Velino Regional Park. From there, autumn migration began on 18 September 2024. The bird reached its first wintering site in Mali by 15 October. It used four wintering areas over 178 days, with a winter home range of 37,615.02 km². Spring migration started on 11 April 2025 and lasted 21 days, ending with arrival in the Gran Sasso e Monti della Laga National Park (Central Italy) on 2 May. The bird used two main sites during the pre-breeding phase (PRBP) before laying eggs on 2 June 2025. The natal dispersal distance, from birthplace to nest site, was 151.28 km. Over 311 days, it covered a total of 14,522.23 km. These findings highlight the value of advanced telemetry in revealing early-life movement ecology and are useful for understanding species-specific patterns of survival, reproduction, and space use and can inform conservation actions.

Reintroductions represent an opportunity to restore local biodiversity and reverse the effect of taxa extinction. However, they need feasibility and monitoring plans before and during their implementation to ensure concrete and lasting results. During the 20th century, the osprey (Pandion haliaetus) underwent a severe population decline in many European countries due to direct persecution and coast exploitation. In the 1960s–1970s, it was declared extinct as a breeder in Italy. In 2004, the Maremma Regional Park (Tuscany, central Italy) started a reintroduction project by capturing and releasing, from 2006 to 2010, 33 juvenile Corsican ospreys on the southern coast of Tuscany. The settlement of the first breeding pair in 2011 was the initial sign of the success of the reintroduction project, then further pairs settled from 2011 onward. A total of 81 feather or blood samples were collected for DNA extraction from both translocated (2006–2010) and newborn individuals (2011–2021). Individuals were analyzed at 16 microsatellite loci to verify any changes in genetic variability over time and to set out a protocol for the reconstruction of kinship for conservation and management purposes. We did not observe a reduction in genetic variability between the two sampling periods, although we found a slight sign of the founder effect in the reestablished population. A strong genetic differentiation was observed between this Mediterranean population and an injured osprey from a Northern European population, thus confirming the importance of considering the local genetic pool in any reintroduction project. Monogamous behavior was confirmed by family reconstruction, which allowed the identification of clear kinship relationships. Our findings indirectly inform on the genetic variability of the population during the 16-year period from the start of the project and provide useful insights for its long-term conservation.