Phenology
| Year | Migration site | First | Migration site | Last | |||||
|---|---|---|---|---|---|---|---|---|---|
| 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 |
