OTWO Magazine October 2019 | Page 64

Manuel Morales Holgado Birding Tarifa Manuel Morales Holgado. Birding Tarifa Article and images When the days start getting shorter, the rains begin to fall, and autumn turns fields from brown to green, most migratory birds have already completed the journey to the African continent. But does that mean the bird migration has ended? At this time of the year, several things transpire in the Straits of Gibraltar, indicating that although 62 the autumn period is entering its final stages, the birds continue to come and go, using this place as a connecting link between the two continents and be- tween the Mediterranean and the Atlantic. During this time of year, a remarkable phenome- non that is spectacular to observe sees huge flocks of hundreds and even thousands of griffon vultures OTWO 03 / OCTOBER 2019 circling in unison in ascending air currents, attemp- ting to reach greater heights to cross into the African continent. This behaviour, which until recently was a mys- tery to ornithologists, occurs between the months of October and December, and is part of the annual mi- gration of juvenile griffon vultures born in Spain, Por- OTWO 03 / OCTOBER 2019 tugal and France; whose main objective is to cross the Straits to feed on the vast amounts of carrion in the African Sahel. Also, it is at this precise time when the chances of observing the scarce black vulture are at its highest throughout the year, since they accompany the gri- ffon vultures on their migratory journey to the south. 63