Phenology
| Year | Migration site | First | Migration site | Last | |||||
|---|---|---|---|---|---|---|---|---|---|
| 2021 | Cap Gris-Nez | 14 April | Cap Gris-Nez | 11 May | |||||
| 2020 | Cap Gris-Nez | 7 October | Cap Gris-Nez | 7 October | |||||
| 2019 | Cap Gris-Nez | 1 September | Cap Gris-Nez | 1 September | |||||
| 2007 | Cap Gris-Nez | 23 April | Cap Gris-Nez | 30 April | |||||
| 2005 | Cap Gris-Nez | 3 April | Cap Gris-Nez | 5 October | |||||
| 2004 | Cap Gris-Nez | 14 May | Cap Gris-Nez | 16 May | |||||
| 1987 | Cap Gris-Nez | 20 October | Cap Gris-Nez | 20 October |
