Phenology
| Year | Migration site | First | Migration site | Last | |||||
|---|---|---|---|---|---|---|---|---|---|
| 2022 |  |
VRS Castricum | 31 May | |
VRS Castricum | 15 June | |||
| 2021 | |
VRS Castricum | 31 May | |
VRS Castricum | 11 July | |||
| 2019 | |
VRS Castricum | 18 June | |
VRS Castricum | 18 June | |||
| 2017 | |
VRS Castricum | 18 June | |
VRS Castricum | 18 June | |||
| 2016 | |
VRS Castricum | 12 June | |
VRS Castricum | 12 June | |||
| 2015 | |
VRS Castricum | 4 June | |
VRS Castricum | 4 June | |||
| 2014 | |
VRS Castricum | 26 May | |
VRS Castricum | 23 June | |||
| 2013 | |
VRS Castricum | 11 June | |
VRS Castricum | 21 July | |||
| 2012 | |
VRS Castricum | 19 June | |
VRS Castricum | 19 June | |||
| 2011 | |
VRS Castricum | 10 June | |
VRS Castricum | 19 July | |||
| 2010 | |
VRS Castricum | 29 June | |
VRS Castricum | 3 July | |||
| 2008 | |
VRS Castricum | 27 June | |
VRS Castricum | 11 July | |||
| 2005 | |
VRS Castricum | 9 July | |
VRS Castricum | 9 July | |||
| 2000 | |
VRS Castricum | 19 May | |
VRS Castricum | 15 July | |||
| 1994 | |
VRS Castricum | 26 May | |
VRS Castricum | 26 May | |||
| 1993 | |
VRS Castricum | 10 July | |
VRS Castricum | 19 July | |||
| 1989 | |
VRS Castricum | 26 May | |
VRS Castricum | 2 July | |||
| 1988 | |
VRS Castricum | 29 May | |
VRS Castricum | 16 July | |||
| 1987 | |
VRS Castricum | 6 June | |
VRS Castricum | 7 August | |||
| 1986 | |
VRS Castricum | 8 June | |
VRS Castricum | 21 June | |||
| 1985 | |
VRS Castricum | 24 July | |
VRS Castricum | 5 August | |||
| 1981 | |
VRS Castricum | 26 July | |
VRS Castricum | 26 July | |||
| 1980 | |
VRS Castricum | 5 July | |
VRS Castricum | 17 July |
