In its determination to promote biodiversity, the Minister of Defense, in collaboration with the Andalusian Government, started a project for the conservation and breeding of the Northern Bald Ibis -also known as Hermit Ibis- (Geronticus Eremita) in the Sierra del Retín range. This bird is included in the list of endangered species. The hermit ibis lives around the Mediterranean Sea in arid or semi-arid steppes.
In the year 2003, experts from the International Advisory Group of the Northern Bald Ibis (IAGNBI), established a series of priorities identifying the south of the Iberian Peninsula as the most favorable habitat for the reproduction of this ibis. The Sierra del Retín range meets all the environmental requirements defined by IAGNBI.
The range, with nearly 5,400 hectares, is one of the few resting areas for migratory birds crossing the Strait of Gibraltar. This ibis lives with other marine birds and raptors in this area with five kilometers of beach ideal for amphibious operations. Training activities and manoeuvers are conducted taking into account, in the first place, environmental requirements, enclosing the military activities to specific areas, thus minimizing the impact. Operations are scheduled and conducted bearing in mind the life cycles of the different fauna.
Some parts of the range have also been fenced and a large aviary built near a cliff with fresh water running throughout the year. Once the aviary was built and protected with an electrical fence to prevent predators from entering, many species from the Jerez Botanical Garden and Zoo were introduced and they soon acclimatized.
After five years, a pair of Northern Bald Ibis successfully bred at the Sierra del Retín range and in 2009 the species began to breed regularly in the wild in the Iberian Peninsula after 500 years.