Phenology
| Year | Migration site | First | Migration site | Last | |||||
|---|---|---|---|---|---|---|---|---|---|
| 2023 |  |
VRS Castricum | 28 April | |
VRS Castricum | 11 May | |||
| 2022 | |
VRS Castricum | 23 April | |
VRS Castricum | 27 April | |||
| 2021 | |
VRS Castricum | 3 May | |
VRS Castricum | 15 May | |||
| 2019 | |
VRS Castricum | 12 May | |
VRS Castricum | 12 May | |||
| 2018 | |
VRS Castricum | 8 May | |
VRS Castricum | 12 May | |||
| 2017 | |
VRS Castricum | 2 May | |
VRS Castricum | 11 May | |||
| 2016 | |
VRS Castricum | 8 May | |
VRS Castricum | 17 September | |||
| 2015 | |
VRS Castricum | 10 May | |
VRS Castricum | 10 May | |||
| 2014 | |
VRS Castricum | 5 May | |
VRS Castricum | 10 May | |||
| 2013 | |
VRS Castricum | 5 May | |
VRS Castricum | 8 May | |||
| 2012 | |
VRS Castricum | 3 May | |
VRS Castricum | 15 May | |||
| 2011 | |
VRS Castricum | 4 May | |
VRS Castricum | 5 May | |||
| 2010 | |
VRS Castricum | 5 May | |
VRS Castricum | 21 May | |||
| 2009 | |
VRS Castricum | 5 May | |
VRS Castricum | 13 June | |||
| 2008 | |
VRS Castricum | 29 April | |
VRS Castricum | 11 October | |||
| 2007 | |
VRS Castricum | 1 May | |
VRS Castricum | 23 May | |||
| 2006 | |
VRS Castricum | 26 April | |
VRS Castricum | 13 May | |||
| 2005 | |
VRS Castricum | 22 April | |
VRS Castricum | 18 May | |||
| 2004 | |
VRS Castricum | 25 April | |
VRS Castricum | 18 May | |||
| 2003 | |
VRS Castricum | 6 May | |
VRS Castricum | 30 May | |||
| 2002 | |
VRS Castricum | 13 May | |
VRS Castricum | 19 September | |||
| 2001 | |
VRS Castricum | 9 May | |
VRS Castricum | 27 May | |||
| 2000 | |
VRS Castricum | 11 April | |
VRS Castricum | 18 May | |||
| 1999 | |
VRS Castricum | 5 May | |
VRS Castricum | 12 November | |||
| 1998 | |
VRS Castricum | 27 April | |
VRS Castricum | 24 November | |||
| 1997 | |
VRS Castricum | 25 April | |
VRS Castricum | 15 October | |||
| 1996 | |
VRS Castricum | 28 April | |
VRS Castricum | 16 September | |||
| 1995 | |
VRS Castricum | 3 May | |
VRS Castricum | 2 October | |||
| 1994 | |
VRS Castricum | 7 May | |
VRS Castricum | 22 May | |||
| 1993 | |
VRS Castricum | 17 May | |
VRS Castricum | 19 September | |||
| 1992 | |
VRS Castricum | 14 May | |
VRS Castricum | 19 September | |||
| 1991 | |
VRS Castricum | 19 May | |
VRS Castricum | 7 October | |||
| 1990 | |
VRS Castricum | 14 May | |
VRS Castricum | 30 September | |||
| 1989 | |
VRS Castricum | 30 March | |
VRS Castricum | 8 April | |||
| 1988 | |
VRS Castricum | 7 September | |
VRS Castricum | 15 October | |||
| 1986 | |
VRS Castricum | 11 August | |
VRS Castricum | 11 August | |||
| 1985 | |
VRS Castricum | 20 September | |
VRS Castricum | 29 October | |||
| 1984 | |
VRS Castricum | 30 September | |
VRS Castricum | 30 September | |||
| 1982 | |
VRS Castricum | 13 September | |
VRS Castricum | 8 October | |||
| 1981 | |
VRS Castricum | 17 May | |
VRS Castricum | 15 October | |||
| 1979 | |
VRS Castricum | 7 September | |
VRS Castricum | 7 September | |||
| 1977 | |
VRS Castricum | 14 September | |
VRS Castricum | 14 September |
