Ernest Garcia
Well-known member
The peak period of southward migration of Griffon Vultures across the Strait of Gibraltar is underway. The Aves Estrecho Gibraltar WhatsApp group today reported a crossing of the Strait at around its narrowest point (16km) by a GPS-tagged Griffon in just 8 minutes, which, if accurate, would suppose a ground speed in excess of 100km/hr. The bird departed the Spanish shore at an altitude of 1,520m, ariving in Morocco at 945m. By way of comparison, the Rock of Gibraltar summit is 425m. My impression is that the bulk of Griffon crossings takes place at much lower altitudes, departing at 600m or lower. The going rate for many raptors is a 20 minute crossing and many take considerably longer. Most Griffon migration at the Strait involves juveniles and older immature birds but this individual seems to have been an adult that seems to have benefited from NW tailwinds at altitude.
