Phenology
| Year | Migration site | First | Migration site | Last | |||||
|---|---|---|---|---|---|---|---|---|---|
| 2021 | De Horde (Lopik) | 1 January | De Horde (Lopik) | 9 May | |||||
| 2020 | De Horde (Lopik) | 6 January | De Horde (Lopik) | 31 December | |||||
| 2019 | De Horde (Lopik) | 7 April | De Horde (Lopik) | 29 November | |||||
| 2018 | De Horde (Lopik) | 28 September | De Horde (Lopik) | 21 October |
