Phenology
| Year | Migration site | First | Migration site | Last | |||||
|---|---|---|---|---|---|---|---|---|---|
| 2020 |  |
VRS Castricum | 11 April | |
VRS Castricum | 24 April | |||
| 2019 | |
VRS Castricum | 22 April | |
VRS Castricum | 22 September | |||
| 2018 | |
VRS Castricum | 7 April | |
VRS Castricum | 22 April | |||
| 2017 | |
VRS Castricum | 1 May | |
VRS Castricum | 15 October | |||
| 2016 | |
VRS Castricum | 1 October | |
VRS Castricum | 1 October | |||
| 2015 | |
VRS Castricum | 5 May | |
VRS Castricum | 5 May | |||
| 2007 | |
VRS Castricum | 23 April | |
VRS Castricum | 23 April | |||
| 2006 | |
VRS Castricum | 7 May | |
VRS Castricum | 9 October | |||
| 2005 | |
VRS Castricum | 25 April | |
VRS Castricum | 25 September | |||
| 2004 | |
VRS Castricum | 20 April | |
VRS Castricum | 18 September | |||
| 2000 | |
VRS Castricum | 23 April | |
VRS Castricum | 12 September | |||
| 1999 | |
VRS Castricum | 24 April | |
VRS Castricum | 8 May | |||
| 1998 | |
VRS Castricum | 26 April | |
VRS Castricum | 23 September | |||
| 1997 | |
VRS Castricum | 6 May | |
VRS Castricum | 27 August | |||
| 1996 | |
VRS Castricum | 9 May | |
VRS Castricum | 9 May | |||
| 1995 | |
VRS Castricum | 24 April | |
VRS Castricum | 10 May | |||
| 1991 | |
VRS Castricum | 19 September | |
VRS Castricum | 8 October | |||
| 1990 | |
VRS Castricum | 8 September | |
VRS Castricum | 27 October | |||
| 1989 | |
VRS Castricum | 30 September | |
VRS Castricum | 30 September | |||
| 1988 | |
VRS Castricum | 12 September | |
VRS Castricum | 17 October | |||
| 1987 | |
VRS Castricum | 13 October | |
VRS Castricum | 13 October | |||
| 1983 | |
VRS Castricum | 29 September | |
VRS Castricum | 29 September | |||
| 1982 | |
VRS Castricum | 24 September | |
VRS Castricum | 24 September | |||
| 1981 | |
VRS Castricum | 18 April | |
VRS Castricum | 13 May | |||
| 1980 | |
VRS Castricum | 2 August | |
VRS Castricum | 2 August | |||
| 1979 | |
VRS Castricum | 4 August | |
VRS Castricum | 21 September | |||
| 1978 | |
VRS Castricum | 7 September | |
VRS Castricum | 7 September | |||
| 1977 | |
VRS Castricum | 21 August | |
VRS Castricum | 1 September | |||
| 1975 | |
VRS Castricum | 10 October | |
VRS Castricum | 10 October |
