Research on nesting activity


By mapping the success of nests we are collecting important information on the breeding success of Dutch birds. Since 1995, this project is an important addition to the endeavour of monitoring breeding birds.  

Research on nesting activity is conducted not only by professional researchers, but also volunteers. Some volunteers notate any nest they come across, while others will annually monitor a group of nests. With the gathered nest activity data, we gain insights into the timing of egg-laying, the percentage of chicks that fledge, and the species specific breeding success. The data is submitted via the Nestkaart and the simpler Nestkaart Light.    


For a nest to be documented, it is must be visited at least two times while the nest is being actively used. Precocial bird nests should be visited between the egg-laying phase and hatching (or failure), whereas the altricial bird nest the period extends from egg-laying and fledging.  

Official exemption 

It is not allowed to visit nests without an exemption. Therefore, it is important to request an exemption from Sovon before you begin. Those who participate in documenting nests are expected to adhere to the code of conduct outlined in the manual and to approach nests cautiously.