Do you want to participate in the Zorzales Project?

The Thrushes Project has established itself as a pioneering initiative in which hunters play a fundamental role in the monitoring and management of these migratory birds. Promoted by Mutuasport, in collaboration with the Artemisan Foundation, the Royal Spanish Hunting Federation, the University of Córdoba, and the Spanish Thrush Association, the project seeks to expand knowledge about the distribution, abundance, and migration patterns of thrushes in Spain.

Despite being one of the most prized small game species by hunters in Spain and Europe, studies on these birds in Spain have been limited. Furthermore, a decline in captures has been detected in recent years, raising concerns in the hunting sector. Given this situation, the project was conceived as a citizen science initiative that, over four years, will analyze the evolution of thrush populations, the factors affecting their migration, and the feasibility of unifying hunting periods in the different autonomous communities.

The Zorzales Project

To achieve this, various data collection methods have been designed, in which hunters actively collaborate. One of the pillars of the study is conducting on-foot censuses using the Hunting Observatory's CensData application, covering a distance of between 4 and 6 kilometers in autumn and winter. These censuses are repeated annually during two key periods: the early wintering period, between November 13 and December 31, and the late wintering period, between January 1 and February 15.

In addition to these censuses, the so-called thrush reserves implement a counting system from fixed positions and collect information on catches during hunting days. In the last season studied, a total of 177 reserves actively participated in this phase of the project, providing valuable data on the density and behavior of thrushes in different areas of Spain.

Another key aspect of the study is the recovery of rings from captured thrushes. This process is essential for tracing their migratory routes and analyzing their survival rates. During the 2021-2022 season, 175 rings were recovered, a figure higher than the 112 from the previous season. The data obtained reveal that most of the ringed thrushes arriving in Spain come from Belgium, followed by other European countries such as Germany, France, the Netherlands, and Poland. Specimens from Finland, Sweden, and Russia have also been identified, confirming the wide geographical distribution of these birds.

As part of the project, new technologies have also been implemented to monitor thrushes. In January 2022, a thrush equipped with a GPS transmitter traveled 3,362 kilometers in 34 days, from Navarre to northern Finland, where its breeding grounds were likely located. Furthermore, studies using bioacoustic devices are being conducted to analyze the song frequency of these birds and delve deeper into their migratory phenology.

Although, according to the International Union for Conservation of Nature (IUCN), the four species of thrushes present in Spain—the common thrush, the redwing, the mistle thrush, and the field thrush—maintain a favorable conservation status, those responsible for the study emphasize the need to continue monitoring their populations. Managing these migratory species is essential to guarantee their long-term conservation and ensure sustainable use in the future.

How to help as a hunter?

The Zorzales Project is embarking on a new season of data collection with the hope of obtaining solid conclusions about the evolution of these birds on the Iberian Peninsula. Hunters and managers interested in participating can join the initiative by emailing zorzales@fundacionartemisan.com or calling 639 714 368, thus contributing to a better understanding and conservation of one of the most emblematic small game species in Spain.

Author: María Balletbó