Phenology
| Year | Migration site | First | Migration site | Last | |||||
|---|---|---|---|---|---|---|---|---|---|
| 2020 | Hobokense Polder | 11 October | Hobokense Polder | 11 October | |||||
| 2017 | Hobokense Polder | 13 October | Hobokense Polder | 13 October | |||||
| 2016 | Hobokense Polder | 1 October | Hobokense Polder | 4 October | |||||
| 2014 | Hobokense Polder | 26 October | Hobokense Polder | 31 October | |||||
| 2013 | Hobokense Polder | 14 October | Hobokense Polder | 14 October | |||||
| 2007 | Hobokense Polder | 4 October | Hobokense Polder | 4 October |
