# CE; # CON; # RES

Project Name: SOS STORK Croatia

Partners: SOS Storch – Storchenzug im Wandel, Lonjsko Polje Nature Park, Euronatur

Project Commencement Year: 2015

Status: Active

Species: White Stork (Ciconia ciconia)

IUCN Red List Status: Least Concern (LC)

Species Status in Croatia (Red Book): Least Concern (LC)

Project Details:

White storks are among the most well-known migratory birds in Croatia, easily recognizable by their striking white wings, which can span up to 1.5 meters. These majestic birds are often seen nesting on rooftops, telephone poles, streetlights, chimneys, and the walls of abandoned houses. Additionally, artificial platforms have been set up to support stork nesting. While they thrive in a variety of habitats—from African savannas and steppes to European meadows, farmlands, and wetlands—storks have also adapted to urban environments where they can find safe nesting sites. In some cases, these urban areas offer additional food sources as well.

In 2000, the Swiss NGO “Stork Switzerland” launched the “SOS Stork” project, which uses satellite telemetry to track storks and identify threats along their western migration route. Data collected from 45 tagged individuals revealed a shift in the behaviour of storks in Western Europe—many spend their first winters in landfills in Andalusia, Spain, which has significantly impacted their migration. However, in 1999, legal regulations were introduced requiring the reduction of organic waste in landfills to 3% by 2016. This change means that the food source in these landfills would no longer be available in the same quantities, posing a challenge for the storks.

The goal of tagging and monitoring storks is to map their migration routes along the eastern flyway, where Croatian storks head south. The project seeks to identify key stopover points and determine whether they are urban areas, meadows, wetlands, or landfills, as well as how far into Africa Croatian storks migrate. Furthermore, the project seeks to identify key threats, such as high-voltage power lines and open water towers. Small transmitters are attached to the storks, which send location data at regular intervals. This data is transmitted via mobile networks to a central system for processing and analysis.

The collaboration between the Zagreb Zoo and “Stork Switzerland” officially began in 2015 when a young stork named Maksi was tagged in its nest in the village of Čigoč, along with a rehabilitated stork named Lonja with a satellite transmitter. The partnership continued in 2016 with the tagging of two adult storks, Leta and Tesla. In 2017, three more storks were tagged—two adults in Čigoč (Pomona and Tesla II) and one young stork in Osekovo (Nikola). In 2018, eight additional storks were tagged, followed by seven more in 2019. Unfortunately, no storks were tagged in 2020 due to the SARS-CoV-2 pandemic. However, in 2021, four young storks were tagged, and in 2022 and 2023, eight storks were tagged each year. In 2024, three more young storks were tagged.

The project received the Euronatur grant for Wet Meadows and Pastures in 2015/2016. EuroNatur and partner organizations, launched the wet meadow conservation project, with the European Stork Villages (ESVN) designated as flagship projects. The project aims to expand and improve the area and quality of wet meadows and pastures within the ESVN network while promoting the exchange of ideas and expertise among Stork Villages across Europe.

Summary:

The white stork monitoring project involves tagging individuals with satellite transmitters to track their movements. The primary goal is to gather detailed information about their migration routes and wintering grounds, while also identifying and mitigating threats such as illegal hunting and collisions with power lines. This initiative contributes to the conservation of white storks and other migratory birds along the eastern migration route. The data collected over the years has provided valuable insights into their behavior, enabling the implementation of more effective conservation measures.