Gibraltar is essentially a large limestone formation covering approximately 2.6 square miles. Human habitation circles the base. The primary vegetation of the upper rock is maquis. This dense growth consists of three hundred and fifty species of flowering plants. There are six species of taller bushes such as Wild Olive and Mediterranean Buckthorn. Smaller bushes include Shrubby Scorpion Vetch and Wild Jasmine. The Sweet Bay and the Dwarf Fan Palm can be found in some areas of the maquis.
Garrigue, consisting of mostly annuals and aromatic herbs dominates smaller areas of the Upper Rock. Common plants are: Wild Rosemary, Esparto Grass and Shrubby Scorpion Vetch. Flowers such as the Giant Squill and Star of Bethlehem can be found growing amongst them.
There are two theories to the origin of the Barbary Macaques
. They may have escaped from a shipment of North African animals transported to Spain or be a remnant of populations that existed in Southern Europe over five million years ago. Alonso Hern'ndez del Portillo, the chronicler of Gibraltar first wrote of the macaques in 1610. The current population is about 300 living in five troops. They are fed a daily diet of fruit, vegetables and grain. They do forage for edible plants and invertibrates as well.
The vast numbers of caves and tunnels make Gibralter an excellent bat habitat. Resident species are; the greater mouse eared bat, Schrieber's bat, European free tailed bat and the Soprano Pipistrelle bat.
The native red fox
became extinct in 1980 and is being reintroduced. Small colonies of European Rabbits
and black rats live on the upper rock. The house mouse
has only been noted near human habitations.
The Eurasian river otter has a wide range, inhabiting streams, rivers and seashores throughout Europe, Asia and Northern Africa.