Photo: A lesser kestrel with an Argos PTT (Green Balkans)
17.12.2019 Animal tracking applications

Where do European Lesser Kestrels go?

The lesser kestrel is a small falcon migrating from Europe to Africa. A study using a large dataset of tracked birds made it possible assess the differences of migration paths and African arrival points depending on their breeding regions in Europe. This can used in devising effective conservation strategies throughout the species’ range.

Photo : A Lesser Kestrel with an Argos PTT. (Credit Green Balkans)

A bird of prey found throughout Southern Europe

An article published on this website explored the success of the reintroduction of lesser kestrels (Falco naumanni) made by Green Balkans in Bulgaria. However, this small bird of prey is found throughout Southern Europe. The reasons for its decline in Eastern Europe – namely the lack of insects to prey upon due to the widespread use of pesticides – are true elsewhere too. A large-scale collaborative tracking study used the information collected from the different European countries where it is found to improve knowledge of its migratory habits.

The migration tracks of 87 individuals, from 25 different breeding sites in Spain, Italy, Greece, France, Bulgaria and Portugal, were analyzed in a continent-wide study. For those tracked with Argos, the PTTs used were all 5 g ones, given the small weight of the bird (ca. 120 g).

Different regions starting and arriving

The study focused on migratory connectivity, reflecting the degree of separation of different breeding populations (from the Iberian, Italian and Balkan peninsulas) in their African non-breeding areas. Results show that birds migrate ca. 3500 km in autumn straight across the Mediterranean and Sahara desert to reach their non-breeding areas in Africa, and ca. 4000 km in spring to make the reverse trip, performing wide westward detours above desert. The non-breeding areas of all birds are within the arid and semi-arid regions of the Sahelian belt, but the species shows a strong migratory connectivity: individuals from different breeding regions tend to migrate to distinct sectors of the Sahel, more than expected by chance. Such a strong migratory connectivity seems a rare occurrence in long‐distance avian migrants.

Post-breeding migration tracks of lesser kestrels from the three main European breeding regions (Iberian, Italian and Balkan peninsulas). The tendency to migrate to distinct sectors from the different breeding regions is quite clear on such a representation, and is corroborated by the statistical analysis of migratory connectivity (modified from Sarà et al. 2019)

Pre-breeding migration tracks of lesser kestrels from the three main European breeding regions (Iberian, Italian and Balkan peninsulas). The tendency to migrate to distinct sectors from the different breeding regions is quite clear on such a representation, and is corroborated by the statistical analysis of migratory connectivity (modified from Sarà et al. 2019)
Post-breeding (left) and pre-breeding (right) migration tracks of lesser kestrels from the three main European breeding regions (Iberian, Italian and Balkan peninsulas). The tendency to migrate to distinct sectors from the different breeding regions is quite clear on such a representation, and is corroborated by the statistical analysis of migratory connectivity (modified from Sarà et al. 2019)

A strong migratory connectivity, such as that observed in this study, implies that different breeding populations will be affected differently by climate variability (e.g. Sahel rainfall variability), which might improve the resilience of this species to climatic and environmental changes occurring in Africa. The study fills an important knowledge gap about the migration routes and African range of different European lesser kestrel populations. These information might be useful to devise effective conservation strategies for different European populations of this threatened falcon.

 

Reference:

Maurizio Sarà, Salvatore Bondì, Ana Bermejo, Mathieu Bourgeois, Mathias Bouzin, Javier Bustamante, Javier de la Puente, Angelos Evangelidis, Annagrazia Frassanito, Egidio Fulco, Giuseppe Giglio, Gradimir Gradev, Matteo Griggio, Lina López‐Ricaurte, Panagiotis Kordopatis, Simeon Marin, Juan Martínez, Rosario Mascara, Ugo Mellone, Stefania C. Pellegrino, Philippe Pilard, Stefano Podofillini, Marta Romero, Marco Gustin, Nicolas Saulnier, Lorenzo Serra, Athanassios Sfougaris, Vicente Urios, Matteo Visceglia, Konstantinos Vlachopoulos, Laura Zanca, Jacopo G. Cecere, Diego Rubolini, 2019: Broad‐front migration leads to strong migratory connectivity in the lesser kestrel (Falco naumanni), Journal of Biogeography (DOI: 10.1111/jbi.13713)