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Brief Report

From Nest to Nest: High-Precision GPS-GSM Tracking Reveals Full Natal Dispersal Process in a First-Year Female Montagu’s Harrier Circus pygargus

by
Giampiero Sammuri
1,
Guido Alari Esposito
2,
Marta De Paulis
3,
Francesco Pezzo
4,
Andrea Sforzi
2 and
Flavio Monti
5,*
1
Servizi per la Ricerca Scientifica e la Tutela della Biodiversità, Via Repubblica di San Marino 28, 58100 Grosseto, Italy
2
Maremma Natural History Museum, Strada Corsini 5, 58100 Grosseto, Italy
3
Reparto Carabinieri Biodiversità L’Aquila, 67100 L’Aquila, Italy
4
Italian Institute for Environmental Protection and Research (ISPRA), Via Ca’ Fornacetta 9, 40064 Ozzano dell’Emilia, Italy
5
Research Institute on Terrestrial Ecosystems (IRET), National Research Council (CNR), Campus Ecotekne, 73100 Lecce, Italy
*
Author to whom correspondence should be addressed.
Birds 2025, 6(3), 40; https://doi.org/10.3390/birds6030040
Submission received: 21 July 2025 / Revised: 31 July 2025 / Accepted: 4 August 2025 / Published: 6 August 2025
(This article belongs to the Special Issue Unveiling the Breeding Biology and Life History Evolution in Birds)
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Simple Summary

Natal dispersal, the movement of an individual from its birthplace to its first breeding site, is a critical ecological process shaping gene flow, population structure, and species distribution. Its study has long been challenging due to the extended and variable time between fledging and first reproduction, especially in long-lived species like raptors, which may take several years to mature. This brief report describes the first fully tracked natal dispersal of a female Montagu’s Harrier Circus pygargus. Equipped with a high-resolution Global Positioning System-Global System for Mobile Communications (GPS-GSM) transmitter as a nestling in Central Italy in July 2024, the bird bred the following year. We document the individual’s entire movement history from fledging to first reproduction, including seasonal migration routes and timing, overwintering locations, and pre-breeding and breeding movements. Such comprehensive tracking allowed for continuous, fine-scale monitoring of movements and reproductive activity. These data provide novel insights into the early life ecology of this species and offer critical information for species-specific conservation planning.

Abstract

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.

1. Introduction

Natal dispersal, the movements that an organism undertakes from its place of origin to its first reproductive site, is a key ecological process, influencing gene flow, population structure, and species distribution [1,2]. Despite being a crucial transitional phase in the lifecycle, studying dispersal has historically been challenging because of the difficulty of monitoring an individual’s movements within a prolonged time-span, i.e., the time between birth and first reproduction. This time can vary in duration and in the extent of the movements carried out, depending on a series of factors such as species, age, sex, life stage and multiple ecological variables [1]. In birds, documenting the full trajectory from fledging to first breeding event in detail is generally difficult, due to wide-ranging pre-breeding movements and the long time lag in reaching sexual maturity and starting reproduction for the first time. In long-lived species, such as raptors, the latter can require from 2 to 5 years [3,4]. Challenges also stem from the fact that the process itself can take various forms, ranging from a gradual shift to a neighboring home range to a one-way movement across a large distance [1,5] or even including seasonal migratory journeys to geographically disjointed areas before breeding [1,6]. For this purpose, spatio-temporal quantitative descriptions of the dispersal process are urgently needed, as pointed out by [2]. Moreover, investigating natal dispersal is essential to better understand the immediate factors influencing the movements of inexperienced juvenile individuals in terms of their transition into the breeding population [6,7].
The advent of advanced GPS-GSM telemetry has revolutionized the field of movement ecology, allowing researchers to collect high-resolution, continuous data on individuals’ movements, behavior, habitat use, and even breeding attempts [8,9,10].
Among raptors, small falcons and accipitrids (e.g., the Common Kestrel Falco tinnunculus and the Eurasian Sparrowhawk Accipiter nisus) exhibit early sexual maturity and can breed in their first calendar year (1 cy). For larger species, breeding in the first calendar year is less common [11]. In the Montagu’s Harrier Circus pygargus, which is considered a medium-size raptor (wingspan: 97–115 cm; weight: 227–445 g) [12], it is reported that sexual maturity is typically reached at 2 or 3 years old [13,14]. Males seldom breed in their first calendar year, yet one documented case describes a year-old male and female successfully rearing three fledglings [15], and another few yearlings have been observed showing breeding behavior [14]. Long-term studies on wing-tag data from nestlings revealed that males first breed at a median age of 3 years in Central Spain and 4 years in western France [13]. Females begin earlier, with median first breeding ages of 2 years in Central Spain and 3 years in western France [13]. Arroyo and Garcia [16], in Central Spain, have recorded that the proportion of breeding females that were in first-year plumage vs. females in adult plumage [17] ranged between 2.0% and 11.1%, depending on the year. Females can hence breed at just 1 year old, although they tend to do so when trophic resources are abundant [18]. The species also show relatively large natal dispersal: wing-tagged birds in Spain showed an average natal dispersal distance of 48 km (range: 2–450 km) and 26 km (range 1–150 km) for females and males, respectively [13].
However, until now, the paucity of GPS tracking studies targeting juveniles [19,20] has hampered the possibility of fully tracking this crucial life stage in detail. In addition, to the best of our knowledge, no detailed information is available on this life stage for the species in Italy, where the species is currently ranked as vulnerable (VU) according to the latest IUCN RedList [21].
In this brief report, we present the first complete natal dispersal and behavioral history of a female Montagu’s Harrier tagged with a high-resolution GPS/GSM transmitter as a pullus in Central Italy in July 2024, which reproduced the following year after 311 days. We report spatio-temporal data from fledging to its first breeding attempt, including seasonal migration timings and routes, wintering, and pre-breeding and breeding movements. These data offer the first fully documented account of the natal dispersal process in Montagu’s Harrier. Such insights help fill a gap in our knowledge of the early life stages in raptors and highlight the ecological relevance of this phase. These insights are useful for understanding species-specific patterns of survival, reproduction, and space use and can guide the definition of informed conservation actions.

2. Materials and Methods

A breeding population of Montagu’s Harriers is being monitored in the province of Grosseto (42.7660° N, 11.1130° E; southern Tuscany), Italy. In July 2024, we trapped 11 Montagu's Harrier chicks from five nests during the last phases of the nestling period [20]. Capture, handling, and tagging procedures were carried out by the Italian Institute for Environmental Protection and Research (ISPRA) under the authorization of Law 157/1992 [Art. 4(1) and Art. 7(5)], which regulates research on wild bird species in Italy.
Seven out of eleven individuals were equipped with 10.8 g solar-powered GPS/GSM transmitters (model Ornitrack-10, Ornitela, Vilnius, Lithuania), provided with an accelerometer sensor that helped record egg laying, incubation, and hatching (e.g., [10]). Further details on logger mounting, device settings, and tracking data processing are provided in [20]. GPS positions were imported into QGIS (v. 3.6.1, Bern, Switzerland) and projected to the Universal Transverse Mercator (UTM) coordinate system for all spatial analyses.
Among these birds, there was a juvenile female (ring code: T69556) who is the subject of this brief report. Here we therefore report the different stages of the early life of bird T69556, from its birth to first reproduction.
The onset of the autumn migration was defined as an abrupt change, indicated by a southward movement of >100 km/day without a return flight towards the north [22], and the reverse was applied for the onset of spring migration (e.g., [23]). Following [24], the end of autumn migration was identified as the day when the bird stopped displacement of >100 km/day for longer than 10 days, after crossing the Sahara Desert. Similarly, the end of spring migration was defined as the day when the bird stopped displacement of >100 km/day for the same time interval. Wintering was between autumn and spring migration. After spring migration, tracking data were further distinguished into the following phases: (i) a “pre-breeding phase” (PRBP), including movements between the arrival after spring migration and the start of egg laying; (ii) an “active breeding phase” (ABP), when a bird behaves as a central place forager [25,26], tightly linked to the nest site. We set this phase to start with the laying of the first egg and to include the incubation and/or nestling–rearing stage.
Once at the breeding site, key dates were assessed per field visits conducted by both personnel of the “Reparto Carabinieri Biodiversità L’Aquila” and members of the working team thanks to the use of a DJI Mini Pro drone with a 4K HD camera (https://www.dji.com/mini-4-pro, accessed on 3 June 2025). Home ranges and core areas were estimated as the 95% (hereafter “HR”) and 50% (hereafter “CA”) Utilization Distribution (UD), respectively, based on GPS locations through the fixed-kernel density estimation (KDE) with reference bandwidth (href) in the R package adehabitatHR [27].

3. Results

Among the seven Montagu’s Harriers tagged in 2024, six started autumn migration, and one individual died shortly after fledging [20]. Five birds successfully reached their wintering grounds in the Sahel region. The GPS signal of the sixth bird ceased sending data in late September 2024, while it was migrating over the Sahara Desert in Algeria. In spring 2025, four individuals (three females and one male) returned to Italy. The GPS of the fifth bird stopped transmitting in mid-April 2025 in Nigeria, shortly after its departure from the wintering grounds. Finally, we obtained direct evidence of reproductive onset from at least one of the three returning females, the data for which are presented below.
The individual was born in June 2024 as part of a brood of three chicks, all of which successfully fledged in July. The natal site was located in the hilly mountainous region of Monte Amiata (42.87° N, 11.53° E) at approximately 900 m above sea level (a.s.l.), in a habitat characterized by scattered vegetation, including bramble and fern thickets, as is typical of the area. In its first year of life, from first flight (26/07/2024) to egg laying (02/06/2025), equal to 311 days, this bird covered 14,522.23 km across Italy and Africa and back. Key dates, duration, and distances covered during each phase across the annual cycle are summarized in Table 1. As the movements from the first flight to departure from the natal area (post-fledging dependence period—PFDP), those preceding the first autumn migration (pre-migratory phase—PMP), as well as the transitions between these phases have been thoroughly analyzed for this individual [20], they are only briefly summarized below.

3.1. Post-Fledging Dependence Period and Pre-Migratory Movements

The first flight occurred on 26 July 2024. The PFDP lasted 31 days. During this period, the home range and core area were 1495.54 km2 and 111.75 km2, respectively. After having left the nest, during the pre-migratory phase, the bird explored different areas, reaching a maximum distance from the nest of 280.80 km. The bird settled in an area ca. 190 km from its place of birth, in the Sirente-Velino Regional Park (42.16601° N, 13.68148° E) in the Apennines. From there it departed for autumn migration. The PMP lasted 23 days.

3.2. Autumn Migration, Wintering, and Spring Migration

Autumn migration started on 18 September 2024. The bird crossed the Tyrrhenian Sea, entered Africa via the Gulf of Sfax, and then flew south-west across the Sahara, skirting the Algeria–Libya border before turning west and reaching Mali in the Sahel region by mid-October (15/10/2024) (Figure 1a). It remained in this first wintering area until 4 November 2024, after which it shifted south to a second site. A further move followed on 14 November 2024 to a third area, and on 6 February 2025, it headed north to a fourth and final wintering location, where it stayed until the onset of spring migration. The winter home range and core area were 37,615.02 km2 and 7108.67 km2, respectively (Figure 1c). Wintering lasted 178 days.
The bird left its wintering grounds on 11/04/2025. During its northbound journey, it flew slightly farther west than on the southward migration (Figure 1a). After crossing the Sahara Desert in Algeria, it traversed the Mediterranean Sea from Cape Bon, northern Tunisia, and made landfall in Italy on 1 May at Ischia Island. The next day it passed directly over the same area that it used during its pre-migratory movements in the Sirente-Velino Regional Park and then continued about 27 km north to the Gran Sasso e Monti della Laga National Park, where it stopped. The entire spring migration lasted 21 days.

3.3. Pre-Breeding Phase (PRBP)

The bird moved in the Gran Sasso e Monti della Laga National Park for one month, until egg laying (2 June 2025). In this period, it used two main sites located 60 km apart (Figure 1b). The first was close to Campo Imperatore (42.41039° N, 13.67990° E), where the bird performed several trips until 09/05/2025. Campo Imperatore is a high-altitude plateau located in the Gran Sasso massif in Central Italy, ranging between 1500 and 2100 m above sea level. Its ecosystem is dominated by alpine and subalpine grasslands, with sparse tree cover, due to both the elevation and harsh climatic conditions. The vegetation includes a rich variety of herbaceous species, such as gentians, saxifrages, and mountain ranunculi. The bird then switched to the second site, in the reserve of Lago of Campotosto (42.534268° N, 13.389069° E) within the Gran Sasso e Monti della Laga National Park, where the bird settled down and built the nest, never returning to the previous site. During this phase, the mean daily distance was 22.93 ± 14 km/d, while the home range and core area were 652.37 km2 and 95.54 km2, respectively (Figure 1b).

3.4. Settlement and Breeding Movements

On 2 June 2025, the bird drastically reduced the frequency of its daily movements and distances covered (Table 1). During this period, the mean daily distance was 0.57 ± 0.47 km/d, while the home range and core area were 0.00331 km2 and 0.00023 km2, respectively. The nest was located at 1440 m a.s.l. in a hilly area ca. 400 m from the lake shore. The area is characterized by a mosaic of montane and subalpine habitats with wide-open meadows, mixed deciduous forests, and shrublands (e.g., blackthorn (Prunus spinosa), hawthorn (Crataegus spp.), and juniper (Juniperus spp.), interspersed with rocky outcrops (Figure 2a). According to the GPS and accelerometer data, the onset of egg laying and incubation was on 02/06/2025 (Figure 2b,c,e), as evidenced by a marked reduction in movements and in the oscillation range of the accelerometer profile, consistent with established behavioral patterns during incubation in birds (e.g., [10]). A subsequent nest survey on 11 June 2025 confirmed the presence of two eggs (Figure 2d). The natal dispersal distance, namely the distance between the birthplace and this nest, was 151.28 km. Incubation lasted ca. 30 days (Table 1). The eggs likely hatched on 3 July 2025, as indicated by accelerometer data (Figure 1c), but breeding ultimately failed, as the individual abandoned the site on the morning of 9 July 2025, and the nest was found empty later that day.

4. Discussion

Our findings present the first fully documented case of natal dispersal in a juvenile Montagu’s Harrier, tracked using high-precision GPS-GSM transmitters. In the bio-logging era [8], collecting detailed spatio-temporal data is increasingly recognized as essential for understanding how juvenile birds drive the transition into the breeding population, an ecological process that ultimately shapes genetic exchange and population dynamics [1,6].
Our results provide evidence that in Italy, juvenile Montagu’s Harriers can not only return to their natal region within the first year of life, but may also attempt to settle in areas with similar environmental characteristics, specifically shrubby areas in mountainous context. This finding is consistent with previous observations from other populations in Spain and France, where first-year breeding by females has been documented through wing-tagging programs [14,19]. However, the technique applied in those earlier studies, while useful in estimating natal dispersal distance, could not provide neither detailed metrics on the distance traveled during each phase of the annual cycle nor the precise timing between them.
Concerning migration and wintering, it has been shown that Montagu’s Harriers breeding in Europe typically follow well-documented geographical patterns characterized by a clockwise loop (e.g., [28]). Their prenuptial (spring) migration route is generally situated further west compared to the postnuptial (autumn) route, reflecting different stopovers and timing strategies [19,28,29]. Our data from this individual align with these general migratory patterns described for the species in Europe. Until now, detailed GPS data on migratory movements for Montagu’s Harriers in Italy have been lacking.
Regarding natal dispersal distance, although some individuals return to their natal sites to reproduce [30], many others may disperse over long distances, sometimes traveling several kilometers from their birthplace [14]. As is common in raptors, Montagu’s Harriers exhibit sex-biased dispersal, with females typically dispersing farther than males. In our study, the observed dispersal distances fall within the known range for the species [13,19]. Notably, the individual settled to breed in a distant area, selecting a similar natural (non-agricultural) habitat to the one where it grew up.
Females are capable of nesting at one year of age, although this seems to primarily occur when food is abundant [18]. A strong interaction between prey cycles and the age of first reproduction has been observed in several raptor species, with one-year-old females initiating nesting during peak food years (e.g., [31]). This suggests that favorable conditions in terms of food abundance, either in the wintering or breeding areas, may have occurred, promoting early reproduction for that individual. Furthermore, it should be noted that first-year breeders often fail to hatch eggs or successfully raise chicks, leading to nest abandonment [32,33]. The current reported case appears consistent with previously reported cases.

5. Conclusions

Using high-precision GPS-GSM tracking allowed us to document the full natal dispersal pathway of a juvenile female Montagu’s Harrier. These represent the first data of this kind for the Italian population for this species. Such evidence fills a major knowledge gap in the species’ early life history. Additional tracking of multiple individuals is, however, essential to build a cumulative data set that will refine our understanding of dispersal variability and inform more effective conservation strategies for this declining raptor, which is classified as vulnerable in Italy. Further investigations might also provide insights that could be of relevance for other populations across Europe, whose migratory routes converge on the Italian peninsula on the way to wintering grounds.
From a conservation perspective, establishing a nest in an area that is different from its native habitat but with similar ecological characteristics opens up new prospects for developing a network of protected areas encompassing multiple breeding sites. The ability of individuals to disperse far and breed in locations beyond the natal area where the species is already present offers hope for boosting the size of small populations through contributions from nearby populations. Based on these early observations, we recommend also directing conservation efforts toward non-agricultural mountain areas, which tend to offer more stable habitat structures compared to the often transient conditions found in agricultural landscapes.

Author Contributions

Conceptualization, G.S. and F.M.; methodology, F.M.; software, F.M.; validation, G.A.E., M.D.P. and F.M.; formal analysis, F.M.; investigation, G.S., G.A.E., M.D.P. and F.P.; resources, G.S.; data curation, F.M.; writing—original draft preparation, F.M.; writing—review and editing, G.S., G.A.E., M.D.P., F.P. and A.S.; visualization, F.M.; supervision, G.S. and F.M.; project administration, G.S.; funding acquisition, G.S. All authors have read and agreed to the published version of the manuscript.

Funding

This research was funded by the “Gioia and Carlo” Foundation.

Institutional Review Board Statement

The animal study protocol was approved by the Tuscany Regional Administration (N: 10543, 16/052024) after the positive opinion expressed by the Italian Institute for Environmental Protection and Research (ISPRA) (Rif. Int. 18502/2024), in accordance with Law157/1992 [Art.4 (1) and Art 7 (5)], which regulates research on wild bird and mammal species.

Informed Consent Statement

Not applicable.

Data Availability Statement

All data are included in the manuscript. In addition, all GPS data analyzed in this study are freely available in the Movebank database (www.movebank.org), project study name “(AlbMar) Circus pygargus in Tuscany/Italy—movement study ID: 4746035954”.

Acknowledgments

We want to thank Eliseo Strinella from the “Reparto Carabinieri Biodiversità L’Aquila” for fieldwork support in Abruzzo and the veterinarian Renato Ceccherelli and its staff at the Centro Recupero Uccelli Marini e Acquatici (CRUMA-LIPU) for the important assistance and support provided during ringing activities at the nests in Tuscany. We also thank Vincenzo Rizzo Pinna and Niccolò Billeri for the support during fieldwork. All volunteers from the Gruppo Ornitologico Maremmano (GOM) who took part in field surveys and helped in detecting Montagu's Harriers’ activity areas are also acknowledged. FM was funded by EU—Next Generation EU Mission 4 “Education and Research”—Component 2: “From research to business”—Investment 3.1: “Fund for the realization of an integrated system of research and innovation infrastructures”—Project IR0000032—ITINERIS—Italian Integrated Environmental Research Infrastructures System—CUP B53C22002150006. The author acknowledges the Research Infrastructures participating in the ITINERIS project with their Italian nodes: ACTRIS, ANAEE, ATLaS, CeTRA, DANUBIUS, DISSCO, e-LTER, ECORD, EMPHASIS, EMSO, EUFAR, Euro-Argo, EuroFleets, Geoscience, IBISBA, ICOS, JERICO, LIFEWATCH, LNS, N/R Laura Bassi, SIOS, and SMINO. The authors thank the four anonymous referees for their valuable suggestions on an earlier version of the manuscript.

Conflicts of Interest

The authors declare no conflicts of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript; or in the decision to publish the results.

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Figure 1. Movements and seasonal home ranges of a first-year breeding female Montagu’s Harrier tracked by a high-precision GPS-GSM transmitter. (a) All GPS locations from its first flight as a fledging in 2024 to its first breeding in spring 2025 are represented by colored dots: orange indicates movements during the PFDP, light blue represents the PMP, black indicates autumn migration movements, purple shows wintering movements within the Sahel region (Mali), red indicates spring migration movements, yellow represents PRBP movements, and green illustrates movements at the breeding site, ABP, until 02/07/2025; (b) home range (light orange) and core area (orange) of pre-breeding movements (yellow dots) in Abruzzo region (Central Italy) between 02/05/2025 and 02/06/2025; (c) home range (light purple) and core area (pink) of winter movements (purple dots) in Mali between 15/10/2024 and 11/04/2025.
Figure 1. Movements and seasonal home ranges of a first-year breeding female Montagu’s Harrier tracked by a high-precision GPS-GSM transmitter. (a) All GPS locations from its first flight as a fledging in 2024 to its first breeding in spring 2025 are represented by colored dots: orange indicates movements during the PFDP, light blue represents the PMP, black indicates autumn migration movements, purple shows wintering movements within the Sahel region (Mali), red indicates spring migration movements, yellow represents PRBP movements, and green illustrates movements at the breeding site, ABP, until 02/07/2025; (b) home range (light orange) and core area (orange) of pre-breeding movements (yellow dots) in Abruzzo region (Central Italy) between 02/05/2025 and 02/06/2025; (c) home range (light purple) and core area (pink) of winter movements (purple dots) in Mali between 15/10/2024 and 11/04/2025.
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Figure 2. Habitat type and behaviors of the female Montagu’s Harrier (T69556) at its first breeding site in the Natural Reserve of Campotosto (Aquila; Italy) in May–June 2025. (a) Aerial image of the breeding site using the DJI Mini Pro drone (Photo © Guido Alari Esposito); (b) the individual T69556 equipped with an Ornitela tag, flying (Photo © Eliseo Strinella); (c) aerial image with the drone of the female T69556 incubating (Photo © Guido Alari Esposito); (d) image of the female’s nest with two eggs (Photo © Eliseo Strinella); (e) graph of the accelerometer data along the three axes (X,Y,Z) for the female T69556, extracted from the Ornitela web panel for 60 days between 09/05/2025 and 07/07/2025. Black dotted arrows represent different females’ behaviors at key dates.
Figure 2. Habitat type and behaviors of the female Montagu’s Harrier (T69556) at its first breeding site in the Natural Reserve of Campotosto (Aquila; Italy) in May–June 2025. (a) Aerial image of the breeding site using the DJI Mini Pro drone (Photo © Guido Alari Esposito); (b) the individual T69556 equipped with an Ornitela tag, flying (Photo © Eliseo Strinella); (c) aerial image with the drone of the female T69556 incubating (Photo © Guido Alari Esposito); (d) image of the female’s nest with two eggs (Photo © Eliseo Strinella); (e) graph of the accelerometer data along the three axes (X,Y,Z) for the female T69556, extracted from the Ornitela web panel for 60 days between 09/05/2025 and 07/07/2025. Black dotted arrows represent different females’ behaviors at key dates.
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Table 1. Key dates, duration (in days), and distances covered of each phase of the first-year breeding female of Montagu’s Harrier, tracked between 2024 and 2025.
Table 1. Key dates, duration (in days), and distances covered of each phase of the first-year breeding female of Montagu’s Harrier, tracked between 2024 and 2025.
PhaseStart
Date		End
Date		Duration
(days)		Cumulative Distance
(km)
PFDP26/07/202426/08/202431551.47
PMP26/08/202418/09/202423672.31
Autumn migration18/09/202415/10/2024273628.09
Winter15/10/202411/04/20251785890.46
Spring migration11/04/202502/05/2025213051.03
PRBP02/05/202501/06/202530710.92
ABP02/06/202502/07/20253017.93
PFDP: post-fledging dependence period; PMP: pre-migratory phase; PRBP: pre-breeding phase; ABP: active breeding phase.
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MDPI and ACS Style

Sammuri, G.; Alari Esposito, G.; De Paulis, M.; Pezzo, F.; Sforzi, A.; Monti, F. From Nest to Nest: High-Precision GPS-GSM Tracking Reveals Full Natal Dispersal Process in a First-Year Female Montagu’s Harrier Circus pygargus. Birds 2025, 6, 40. https://doi.org/10.3390/birds6030040

AMA Style

Sammuri G, Alari Esposito G, De Paulis M, Pezzo F, Sforzi A, Monti F. From Nest to Nest: High-Precision GPS-GSM Tracking Reveals Full Natal Dispersal Process in a First-Year Female Montagu’s Harrier Circus pygargus. Birds. 2025; 6(3):40. https://doi.org/10.3390/birds6030040

Chicago/Turabian Style

Sammuri, Giampiero, Guido Alari Esposito, Marta De Paulis, Francesco Pezzo, Andrea Sforzi, and Flavio Monti. 2025. "From Nest to Nest: High-Precision GPS-GSM Tracking Reveals Full Natal Dispersal Process in a First-Year Female Montagu’s Harrier Circus pygargus" Birds 6, no. 3: 40. https://doi.org/10.3390/birds6030040

APA Style

Sammuri, G., Alari Esposito, G., De Paulis, M., Pezzo, F., Sforzi, A., & Monti, F. (2025). From Nest to Nest: High-Precision GPS-GSM Tracking Reveals Full Natal Dispersal Process in a First-Year Female Montagu’s Harrier Circus pygargus. Birds, 6(3), 40. https://doi.org/10.3390/birds6030040

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