Phenology
| Year | Migration site | First | Migration site | Last | |||||
|---|---|---|---|---|---|---|---|---|---|
| 2022 |  |
VRS Castricum | 12 April | |
VRS Castricum | 17 July | |||
| 2021 | |
VRS Castricum | 31 March | |
VRS Castricum | 3 July | |||
| 2020 | |
VRS Castricum | 25 March | |
VRS Castricum | 3 July | |||
| 2019 | |
VRS Castricum | 7 April | |
VRS Castricum | 4 June | |||
| 2018 | |
VRS Castricum | 26 March | |
VRS Castricum | 23 July | |||
| 2017 | |
VRS Castricum | 26 March | |
VRS Castricum | 7 July | |||
| 2016 | |
VRS Castricum | 31 March | |
VRS Castricum | 21 July | |||
| 2015 | |
VRS Castricum | 16 April | |
VRS Castricum | 16 July | |||
| 2014 | |
VRS Castricum | 1 April | |
VRS Castricum | 12 July | |||
| 2013 | |
VRS Castricum | 16 April | |
VRS Castricum | 4 July | |||
| 2012 | |
VRS Castricum | 30 April | |
VRS Castricum | 28 June | |||
| 2011 | |
VRS Castricum | 28 March | |
VRS Castricum | 28 June | |||
| 2010 | |
VRS Castricum | 30 March | |
VRS Castricum | 22 July | |||
| 2009 | |
VRS Castricum | 6 April | |
VRS Castricum | 21 July | |||
| 2008 | |
VRS Castricum | 7 June | |
VRS Castricum | 13 July | |||
| 2006 | |
VRS Castricum | 9 June | |
VRS Castricum | 16 July | |||
| 2004 | |
VRS Castricum | 22 July | |
VRS Castricum | 5 August | |||
| 2003 | |
VRS Castricum | 29 March | |
VRS Castricum | 29 March | |||
| 2001 | |
VRS Castricum | 14 June | |
VRS Castricum | 14 July | |||
| 2000 | |
VRS Castricum | 11 April | |
VRS Castricum | 18 April | |||
| 1999 | |
VRS Castricum | 31 March | |
VRS Castricum | 3 August | |||
| 1998 | |
VRS Castricum | 20 July | |
VRS Castricum | 20 July | |||
| 1997 | |
VRS Castricum | 28 June | |
VRS Castricum | 15 July | |||
| 1996 | |
VRS Castricum | 8 April | |
VRS Castricum | 8 April | |||
| 1995 | |
VRS Castricum | 11 April | |
VRS Castricum | 1 August | |||
| 1994 | |
VRS Castricum | 21 April | |
VRS Castricum | 21 August | |||
| 1993 | |
VRS Castricum | 4 July | |
VRS Castricum | 4 July | |||
| 1992 | |
VRS Castricum | 29 March | |
VRS Castricum | 22 August | |||
| 1991 | |
VRS Castricum | 11 July | |
VRS Castricum | 10 August | |||
| 1990 | |
VRS Castricum | 30 April | |
VRS Castricum | 29 July | |||
| 1984 | |
VRS Castricum | 5 August | |
VRS Castricum | 5 August | |||
| 1981 | |
VRS Castricum | 12 August | |
VRS Castricum | 12 August |
