Phenology
| Year | Migration site | First | Migration site | Last | |||||
|---|---|---|---|---|---|---|---|---|---|
| 2022 |  |
VRS Castricum | 12 July | |
VRS Castricum | 18 December | |||
| 2021 | |
VRS Castricum | 12 February | |
VRS Castricum | 13 February | |||
| 2019 | |
VRS Castricum | 16 August | |
VRS Castricum | 16 August | |||
| 2018 | |
VRS Castricum | 1 March | |
VRS Castricum | 3 March | |||
| 2017 | |
VRS Castricum | 21 June | |
VRS Castricum | 16 August | |||
| 2016 | |
VRS Castricum | 18 August | |
VRS Castricum | 18 August | |||
| 2015 | |
VRS Castricum | 4 July | |
VRS Castricum | 28 September | |||
| 2013 | |
VRS Castricum | 18 January | |
VRS Castricum | 30 September | |||
| 2012 | |
VRS Castricum | 2 February | |
VRS Castricum | 1 September | |||
| 2010 | |
VRS Castricum | 3 January | |
VRS Castricum | 21 December | |||
| 2009 | |
VRS Castricum | 6 January | |
VRS Castricum | 22 December | |||
| 2008 | |
VRS Castricum | 1 July | |
VRS Castricum | 2 July | |||
| 2005 | |
VRS Castricum | 3 March | |
VRS Castricum | 3 March | |||
| 2004 | |
VRS Castricum | 6 August | |
VRS Castricum | 23 August | |||
| 2003 | |
VRS Castricum | 7 January | |
VRS Castricum | 26 August | |||
| 2002 | |
VRS Castricum | 10 December | |
VRS Castricum | 13 December | |||
| 2001 | |
VRS Castricum | 17 January | |
VRS Castricum | 18 August | |||
| 2000 | |
VRS Castricum | 14 August | |
VRS Castricum | 2 September | |||
| 1999 | |
VRS Castricum | 30 July | |
VRS Castricum | 3 November | |||
| 1998 | |
VRS Castricum | 13 August | |
VRS Castricum | 29 August | |||
| 1997 | |
VRS Castricum | 1 January | |
VRS Castricum | 28 September | |||
| 1996 | |
VRS Castricum | 1 January | |
VRS Castricum | 29 December | |||
| 1995 | |
VRS Castricum | 7 January | |
VRS Castricum | 31 December | |||
| 1994 | |
VRS Castricum | 20 February | |
VRS Castricum | 2 September | |||
| 1993 | |
VRS Castricum | 1 January | |
VRS Castricum | 1 December | |||
| 1992 | |
VRS Castricum | 18 August | |
VRS Castricum | 31 December | |||
| 1991 | |
VRS Castricum | 3 February | |
VRS Castricum | 31 July | |||
| 1990 | |
VRS Castricum | 26 July | |
VRS Castricum | 23 October | |||
| 1989 | |
VRS Castricum | 9 February | |
VRS Castricum | 4 December | |||
| 1988 | |
VRS Castricum | 17 July | |
VRS Castricum | 4 November | |||
| 1987 | |
VRS Castricum | 7 January | |
VRS Castricum | 3 October | |||
| 1986 | |
VRS Castricum | 11 August | |
VRS Castricum | 6 September | |||
| 1985 | |
VRS Castricum | 9 January | |
VRS Castricum | 10 September | |||
| 1984 | |
VRS Castricum | 14 November | |
VRS Castricum | 14 November | |||
| 1983 | |
VRS Castricum | 6 August | |
VRS Castricum | 27 September | |||
| 1982 | |
VRS Castricum | 30 July | |
VRS Castricum | 13 September | |||
| 1981 | |
VRS Castricum | 7 August | |
VRS Castricum | 22 December | |||
| 1980 | |
VRS Castricum | 13 January | |
VRS Castricum | 30 September | |||
| 1979 | |
VRS Castricum | 13 February | |
VRS Castricum | 27 September | |||
| 1978 | |
VRS Castricum | 12 August | |
VRS Castricum | 21 December | |||
| 1977 | |
VRS Castricum | 18 August | |
VRS Castricum | 19 August | |||
| 1976 | |
VRS Castricum | 30 January | |
VRS Castricum | 1 March |
