The Migration of Birds across the Straits of Gibraltar

The Straits of Gibraltar is the narrowest channel separating Europe and Africa, therefore a key point to migrating birds. Storks concentrates here until favorable thermal currents allow them to cross safely the sea on their migratory journeys between the two continents. At the moment, probably due to the extensive use of dumps and the protection of nests, stork is the species with most migrating individuals. They can form flocks of up to five thousands birds, which offer a most impressive spectacle when approaching and escaping the coast.

The Straits of Gibraltar is also the scene of significant migration of raptors and seabirds. Until October, short-toed eagles, harriers, kestrels, and buzzards, stroll around the Straits, the last being the superb, and not very well known, migration of griffon vultures. Even less studied is the crossing of cranes, flamingoes, spoonbills, and waders.

Some species, like flamingoes and herons, prefer migrating at night, when less predators are found. Others, especially seabirds, are difficult to observe too, as they travel very far from the coast and close to the water. The behaviour of migrating birds varies according to the regimes of winds that blow with famous strenght and persistence in the area of the Straits. On occasions, inexperts and exhausted animals have been seen falling into the foamy waves without possibility of survival, or have been pushed by the wind into the Atlantic Ocean, following the same tragic fate.

The migration of birds across the Straits has been studied for years. In 1997, the Sociedad Española de Ornitología (SEO) and the Andalucian Government started a complete monitoring programme (MIGRES) aimed at studying the numeric fluctuations of the different species for conservation goals.