Phenology
| Year | Migration site | First | Migration site | Last | |||||
|---|---|---|---|---|---|---|---|---|---|
| 2022 |  |
VRS Castricum | 12 April | |
VRS Castricum | 27 August | |||
| 2021 | |
VRS Castricum | 4 April | |
VRS Castricum | 7 September | |||
| 2020 | |
VRS Castricum | 16 April | |
VRS Castricum | 15 September | |||
| 2019 | |
VRS Castricum | 14 July | |
VRS Castricum | 23 August | |||
| 2018 | |
VRS Castricum | 12 April | |
VRS Castricum | 29 August | |||
| 2017 | |
VRS Castricum | 1 August | |
VRS Castricum | 14 August | |||
| 2016 | |
VRS Castricum | 21 July | |
VRS Castricum | 27 August | |||
| 2015 | |
VRS Castricum | 2 July | |
VRS Castricum | 14 September | |||
| 2014 | |
VRS Castricum | 16 July | |
VRS Castricum | 2 September | |||
| 2013 | |
VRS Castricum | 17 July | |
VRS Castricum | 27 August | |||
| 2012 | |
VRS Castricum | 22 July | |
VRS Castricum | 21 August | |||
| 2011 | |
VRS Castricum | 23 April | |
VRS Castricum | 18 August | |||
| 2010 | |
VRS Castricum | 8 August | |
VRS Castricum | 31 August | |||
| 2009 | |
VRS Castricum | 6 August | |
VRS Castricum | 19 August | |||
| 2008 | |
VRS Castricum | 23 July | |
VRS Castricum | 12 September | |||
| 2007 | |
VRS Castricum | 16 July | |
VRS Castricum | 12 September | |||
| 2006 | |
VRS Castricum | 16 July | |
VRS Castricum | 23 August | |||
| 2005 | |
VRS Castricum | 6 August | |
VRS Castricum | 23 September | |||
| 2004 | |
VRS Castricum | 17 August | |
VRS Castricum | 17 August | |||
| 2003 | |
VRS Castricum | 21 April | |
VRS Castricum | 26 September | |||
| 2002 | |
VRS Castricum | 8 August | |
VRS Castricum | 19 September | |||
| 2001 | |
VRS Castricum | 30 August | |
VRS Castricum | 30 August | |||
| 2000 | |
VRS Castricum | 23 August | |
VRS Castricum | 24 August | |||
| 1999 | |
VRS Castricum | 1 August | |
VRS Castricum | 28 August | |||
| 1998 | |
VRS Castricum | 12 August | |
VRS Castricum | 29 August | |||
| 1996 | |
VRS Castricum | 18 May | |
VRS Castricum | 15 September | |||
| 1994 | |
VRS Castricum | 6 September | |
VRS Castricum | 6 September |
