Phenology
| Year | Migration site | First | Migration site | Last | |||||
|---|---|---|---|---|---|---|---|---|---|
| 2022 | Cap Gris-Nez | 2 May | Cap Gris-Nez | 10 December | |||||
| 2021 | Cap Gris-Nez | 1 March | Cap Gris-Nez | 2 December | |||||
| 2020 | Cap Gris-Nez | 10 October | Cap Gris-Nez | 10 October | |||||
| 2019 | Cap Gris-Nez | 22 October | Cap Gris-Nez | 22 October | |||||
| 2016 | Cap Gris-Nez | 20 October | Cap Gris-Nez | 13 November | |||||
| 2015 | Cap Gris-Nez | 22 November | Cap Gris-Nez | 22 November | |||||
| 2013 | Cap Gris-Nez | 24 February | Cap Gris-Nez | 24 February | |||||
| 2012 | Cap Gris-Nez | 7 April | Cap Gris-Nez | 2 December | |||||
| 2011 | Cap Gris-Nez | 7 October | Cap Gris-Nez | 18 December | |||||
| 2009 | Cap Gris-Nez | 22 February | Cap Gris-Nez | 1 November | |||||
| 2008 | Cap Gris-Nez | 30 September | Cap Gris-Nez | 26 October | |||||
| 2007 | Cap Gris-Nez | 6 November | Cap Gris-Nez | 11 November | |||||
| 2006 | Cap Gris-Nez | 3 October | Cap Gris-Nez | 10 December | |||||
| 2005 | Cap Gris-Nez | 14 October | Cap Gris-Nez | 26 November | |||||
| 1987 | Cap Gris-Nez | 19 October | Cap Gris-Nez | 23 October | |||||
| 1986 | Cap Gris-Nez | 19 October | Cap Gris-Nez | 24 October | |||||
| 1977 | Cap Gris-Nez | 2 October | Cap Gris-Nez | 2 October |
