Phenology
| Year | Migration site | First | Migration site | Last | |||||
|---|---|---|---|---|---|---|---|---|---|
| 2023 | Cap Gris-Nez | 20 May | Cap Gris-Nez | 20 May | |||||
| 2022 | Cap Gris-Nez | 16 April | Cap Gris-Nez | 2 August | |||||
| 2021 | Cap Gris-Nez | 17 August | Cap Gris-Nez | 23 September | |||||
| 2020 | Cap Gris-Nez | 26 September | Cap Gris-Nez | 26 September | |||||
| 2018 | Cap Gris-Nez | 21 May | Cap Gris-Nez | 11 September | |||||
| 2017 | Cap Gris-Nez | 12 September | Cap Gris-Nez | 12 September | |||||
| 2016 | Cap Gris-Nez | 28 August | Cap Gris-Nez | 8 September | |||||
| 2015 | Cap Gris-Nez | 8 May | Cap Gris-Nez | 14 August | |||||
| 2012 | Cap Gris-Nez | 2 May | Cap Gris-Nez | 2 May | |||||
| 2011 | Cap Gris-Nez | 28 August | Cap Gris-Nez | 17 September | |||||
| 2010 | Cap Gris-Nez | 21 August | Cap Gris-Nez | 21 August | |||||
| 2009 | Cap Gris-Nez | 5 September | Cap Gris-Nez | 6 September | |||||
| 2007 | Cap Gris-Nez | 6 May | Cap Gris-Nez | 22 September | |||||
| 2006 | Cap Gris-Nez | 30 July | Cap Gris-Nez | 28 September | |||||
| 2005 | Cap Gris-Nez | 8 May | Cap Gris-Nez | 26 October | |||||
| 2004 | Cap Gris-Nez | 16 May | Cap Gris-Nez | 16 May | |||||
| 1961 | Cap Gris-Nez | 8 September | Cap Gris-Nez | 8 September |
