On north- facing slopes there are well established Holm oaks, Aleppo pine plantations and native ‘laricio pine', Phoenician juniper', ‘genistas', rock roses and aromatic plants like thyme, lavender and rosemary.
The park's limestone terrain is characterised by numerous fissures and crevices, creating a unique microclimate. There are more than 1,200 species of plants to be found in the Natural Park. It supports a varied flora with nearly half of all plant species in Almeria province found here, including some unique to the Sierra.
Similarly diverse is the park's fauna, with more than 125 species. The park has the largest gathering of birds of prey per square kilometre in the whole of Andalucía. In 2002 it was declared a special protection zone for birds. Dominating the skies above the highest, rockiest peaks are golden eagles, booted eagles, goshawks, sparrow hawks, and peregrine falcons. The griffon vulture is also being re- introduced to the area. There are also eagle owls, little owls, barn owls, scops owl, long eared owl and short eared owls.
Lower down in the forests are great tits, crested tits, gold crests, long- tailed tits, short- toed tree creepers. Out in the open areas you may spot a colourful bee- eater or hoopoe, meadow pipits, crested larks or calandra larks.
The dense forests are also home to foxes, polecats, wild boar, badgers, weasels and red squirrels, along with reptiles including ladder snakes and ocelated lizards.
The parks butterfly population is outstanding and includes a subspecies of the butterfly Parnassius Apollo, which can only be found in the Sierra, and the Pseudochazara Hipolyte, endemic to southeast Spain.
The spur- thighed tortoise that inhabits the Sierra is in danger of extinction and there is a breeding centre for these tortoises in the north of the park at Las Almohallas