Phenology
| Year | Migration site | First | Migration site | Last | |||||
|---|---|---|---|---|---|---|---|---|---|
| 2020 |  |
VRS Castricum | 4 August | |
VRS Castricum | 15 August | |||
| 2019 | |
VRS Castricum | 29 June | |
VRS Castricum | 28 July | |||
| 2018 | |
VRS Castricum | 4 March | |
VRS Castricum | 16 September | |||
| 2017 | |
VRS Castricum | 19 September | |
VRS Castricum | 19 September | |||
| 2016 | |
VRS Castricum | 10 March | |
VRS Castricum | 26 August | |||
| 2015 | |
VRS Castricum | 1 September | |
VRS Castricum | 9 September | |||
| 2014 | |
VRS Castricum | 25 May | |
VRS Castricum | 12 September | |||
| 2013 | |
VRS Castricum | 28 May | |
VRS Castricum | 13 September | |||
| 2012 | |
VRS Castricum | 29 February | |
VRS Castricum | 6 September | |||
| 2011 | |
VRS Castricum | 24 February | |
VRS Castricum | 22 August | |||
| 2010 | |
VRS Castricum | 2 March | |
VRS Castricum | 5 September | |||
| 2009 | |
VRS Castricum | 21 March | |
VRS Castricum | 25 August | |||
| 2008 | |
VRS Castricum | 4 April | |
VRS Castricum | 27 July | |||
| 2007 | |
VRS Castricum | 13 March | |
VRS Castricum | 6 September | |||
| 2006 | |
VRS Castricum | 24 March | |
VRS Castricum | 23 August | |||
| 2005 | |
VRS Castricum | 26 May | |
VRS Castricum | 13 September | |||
| 2004 | |
VRS Castricum | 30 May | |
VRS Castricum | 25 September | |||
| 2003 | |
VRS Castricum | 23 May | |
VRS Castricum | 16 September | |||
| 2002 | |
VRS Castricum | 11 August | |
VRS Castricum | 12 September | |||
| 2001 | |
VRS Castricum | 14 September | |
VRS Castricum | 14 September | |||
| 2000 | |
VRS Castricum | 3 July | |
VRS Castricum | 21 September | |||
| 1999 | |
VRS Castricum | 5 September | |
VRS Castricum | 10 September | |||
| 1998 | |
VRS Castricum | 24 August | |
VRS Castricum | 18 September | |||
| 1997 | |
VRS Castricum | 25 May | |
VRS Castricum | 20 September | |||
| 1996 | |
VRS Castricum | 12 March | |
VRS Castricum | 14 September | |||
| 1995 | |
VRS Castricum | 24 May | |
VRS Castricum | 18 September | |||
| 1994 | |
VRS Castricum | 11 July | |
VRS Castricum | 18 September | |||
| 1993 | |
VRS Castricum | 29 August | |
VRS Castricum | 10 September | |||
| 1992 | |
VRS Castricum | 20 July | |
VRS Castricum | 19 September | |||
| 1991 | |
VRS Castricum | 15 August | |
VRS Castricum | 10 October | |||
| 1990 | |
VRS Castricum | 26 July | |
VRS Castricum | 27 August | |||
| 1989 | |
VRS Castricum | 12 March | |
VRS Castricum | 25 September | |||
| 1988 | |
VRS Castricum | 9 August | |
VRS Castricum | 7 September | |||
| 1987 | |
VRS Castricum | 13 March | |
VRS Castricum | 9 September | |||
| 1986 | |
VRS Castricum | 5 September | |
VRS Castricum | 19 November | |||
| 1985 | |
VRS Castricum | 30 August | |
VRS Castricum | 23 September | |||
| 1984 | |
VRS Castricum | 1 August | |
VRS Castricum | 2 August | |||
| 1983 | |
VRS Castricum | 9 August | |
VRS Castricum | 9 August | |||
| 1982 | |
VRS Castricum | 3 August | |
VRS Castricum | 3 October | |||
| 1981 | |
VRS Castricum | 25 August | |
VRS Castricum | 31 August | |||
| 1980 | |
VRS Castricum | 1 September | |
VRS Castricum | 8 September | |||
| 1979 | |
VRS Castricum | 2 September | |
VRS Castricum | 2 September | |||
| 1978 | |
VRS Castricum | 1 September | |
VRS Castricum | 1 September | |||
| 1977 | |
VRS Castricum | 16 August | |
VRS Castricum | 8 September | |||
| 1976 | |
VRS Castricum | 15 August | |
VRS Castricum | 31 August |
