Passionate local observers throughout Belgium have played a crucial role in monitoring the well-being of the population of white storks (Ciconia ciconia), tracking not only the number of occupied nests but also recording breeding success. As a result, the white stork has become one of the most closely monitored bird species in Belgium.
Record numbers in 2023
In 2023, there were 248 occupied nest sites, marking a significant 12% increase compared to the previous record of 221 nests in 2022. While historical records suggest white storks may have once been more abundant in Belgium, their numbers dwindled significantly by the 19th century due to habitat loss and human persecution.
The 20th century saw a decline in stork populations across Western Europe, but conservation efforts and reintroduction projects initiated a positive turnaround. Belgium, too, witnessed the impact of these efforts, with the stork population growing slowly at first and then accelerating in the past 10-15 years. Starting with less than 50 pairs at the beginning of the 21st century, the Belgian stork population now boasts five times that number.
Planckendael holds the most nests
The geographical distribution of the 248 breeding sites in 2023 revealed that approximately three-quarters were located in Flanders. Antwerp and West Flanders, where major reintroduction projects occurred, accounted for 85% of the nests. Planckendael, with 93 occupied breeding sites, remains the largest breeding center.
While some stork pairs concentrated in specific areas, there was a noteworthy trend of new couples settling outside traditional core areas. The Dender Valley in the southeast of East Flanders, for instance, saw an increase from one pair in 2013 to five pairs by 2023, resembling a small population core.
In Wallonia, the remaining 66 breeding sites were concentrated in Hainaut and Liège. The Pairi Daizi animal park in Hainaut played a significant role with 51 breeding sites. Similar to Flanders, there were instances of newly occupied breeding grounds at a distance from known centers in Wallonia.
Examining breeding success, 12.5% of breeding sites had pairs occupying nests without making a breeding attempt, primarily involving young birds attempting to breed for the first time. Of the remaining sites, 64.5% saw successful breeding, resulting in 368 young white storks. While this is slightly lower than the 2022 results, weather-related factors, particularly in late April and early May, were reported as causes for some breeding failures.
Counting storks internationally
Looking ahead, a new international census of the stork population is scheduled for 2024. Conducted every ten years since 1974, this census will provide valuable insights into the overall status and trends of stork populations across North Africa, Europe, and western Asia. The anticipation is high as observers eagerly await the developments in the stork population.