Sierra Nevada National Park

The Cordilleras Béticas are a series of mountain ranges that extend throughout southeastern Spain, from the province of Murcia to the Strait of Gibraltar. Its boundaries lie between the Guadalquivir Depression to the north and the Mediterranean Sea to the south and east.

The Sierra Nevada National Park, with an area of 86,208 ha, is a clearly differentiated geographical unit, located to the southeast of the city of Granada, and also includes the western end of the province of Almería.

It includes 15 municipalities in the province of Almería and 29 in the province of Granada.

The origin of the Sierra Nevada
This mountain massif arose as a result of the Alpine orogeny in the Tertiary period. Since then, it has not stopped rising until it reached the highest peaks on the peninsula. But the current morphology is also the result of glacial episodes at the end of the Quaternary. The summit area preserves a unique glacial relief, modelled by the Quaternary glaciations in the southernmost high mountain massif on the European continent.

15 summits are over 3,000 m high.
The relief of the Sierra Nevada has gentle forms and ridges, although in some parts of the massif, such as the headwaters of the Genil, it can be steep and rugged. The highest peaks of the Peninsula are located here, the Mulhacén (3,482 m) and the Veleta (3,392 m). Its relief is also of extraordinary geomorphological interest due to the existing glacial and periglacial modelling and the still active periglacial dynamics that continue to act from 2,500-2,600 m above sea level.

The entire summit area shows traces of glacial erosion, with U-shaped valleys, cirques crowned by abrupt mountain ranges and lagoons occupying the depressions. The glacial forms that appear in the Sierra Nevada are very varied. Glacial cirques are relatively abundant, the most evolved ones being found in the high summit areas and the incipient ones in lower areas.

A core of Palaeozoic materials
Geologically, there are three concentric zones:

• The central core of Sierra Nevada, where the highest peaks of the massif emerge, formed by metamorphic rocks (schists, slates). This area is known as the “lastra”.
• Surrounding this area is an inner rim of Triassic soils, made up of slates, marbles, serpentines, gneisses and clayey phyllites, composed of crumbly fragments that make up the “launa”, used as waterproofing in the roofs of the houses of the Alpujarras. From a floristic point of view, the serpentines of the Almirez and the marbles of the Trevélez river are important.
• Further out, there is a belt of limestone and dolomites, which form the characteristic “calar”. It is in the extreme W-NW where this limestone rim is most clearly visible, where an abrupt and intricate relief originates, with well-differentiated peaks such as the Trevenque needle (2,079 m), the Dornajo crests (2,076 m), Alayos de Dílar (1,980 m), and spectacular narrows such as the Monachil cahorros. Finally, the Neogene and Quaternary periods are represented by soft rocks, such as marl, sand, conglomerates, etc. In these places the xericity is very marked.

Snow: a reservoir of water resources
On the summits, rainfall of around 2,000 mm provides a considerable layer of snow and, therefore, a good reserve of water resources.

In the Sierra Nevada, summers are mild and winters are cold with frequent frosts, especially in the golden and cryo-Mediterranean levels. From January to August temperatures gradually rise and then decline from September onwards.

Above 1,800 m altitude, at least 30% of precipitation is in the form of snow, and above 2,500 m 95%. This causes runoff in the shales, which is drained by gullies and streams.

Snow-fed streams and rivers
The hydrographic network is extensive, and is made up of numerous streams, rivers and ravines, which, fed by the snows, have little water in winter and a high flow in spring and early summer.in the extreme southwest runs the river Izbor, which collects the waters of smaller rivers that originate in the central core of the Sierra Nevada. Further north runs the Genil, which collects the waters of the northern slopes and flows into the Guadalquivir. The Guadalfeo, Adra and Andarax rivers originate on the southern slopes of the Sierra. This fluvial network has a strong influence on the landscape and is closely related to erosion, which is at its maximum between 800 and 2,000 m above sea level.

Numerous and extensive aquifers
The aquifers are numerous and extensive, some of them with mineral springs. In the town of Lanjarón you can find the famous mineral water bottling factory, as well as a spa where you can enjoy the medicinal properties of these waters.

Biological diversity is the main ecological value of the Sierra Nevada, especially in terms of vascular flora, with more than 2,100 species catalogued out of the nearly 8,000 existing in the Iberian Peninsula. Sierra Nevada has 7% of the vascular flora existing in the Mediterranean Region; taking into account that this massif barely represents one hundredth of the total surface area of this biogeographical region, it gives an idea of the quality of this unique sample of natural heritage.

The harsh climate of the Quaternary glaciations in Europe caused a retreat of vegetation to lower latitudes, and so species from northern Europe arrived in the Sierra Nevada. The permanence of many of these species was favoured by the interglacial periods. Some of these species sought their optimum environment by climbing to the top of the mountains, where the climate was similar to that of their origin. Later, due to isolation, some of these plants developed into new species or races, many of them vicariants of some alpine or Pyrenean plants, thus increasing the number of endemic species typical of this massif.

The endemic element

The endemic element is very high: around 65 exclusive species and 175 Iberian endemisms. This is due to a close tolerance to some limiting environmental factor, the existence of geographical barriers, recent genesis and changes in climatic conditions. In addition, 65 of the 181 taxa that make up the regional catalogue of threatened wild flora are represented. Artemisia granatensis, Arenaria nevadensis, Erodium astragaloides, Erodium rupicola, Laserpitium longiradium, Narcissus nevadensis, Senecio elodes and Sarcocapnos crassifolia subsp. speciosa are listed as “in danger of extinction” by Royal Decree 439/90, of 30 March, which regulates the general catalogue of endangered species.

There are also 18 taxa that appear in Annex II, 9 of which are priority taxa (Royal Decree 1997/95, of 7 December), of Community interest and for whose protection it is necessary to designate special conservation areas.

Types of endemisms

• Baetic endemisms: although they are not exclusive to the Sierra Nevada massif, they have a close distribution in the Baetic and Sub-Baetic mountain ranges.
• Endemic species of the Malacitano-Almijarense sector: their distribution extends across the Axarquía in Malaga, the Tejeda and Almijara mountain ranges and the limestone-dolomitic portion of the Sierra Nevada.
• Endemisms of the Alpujarro-Ggadorense sector: they occupy the coastal foothills of the Betic mountain ranges.
• Endemic species of the Nevadense sector, i.e. those whose distribution is restricted to the Sierra Nevada and Sierra de los Filabres.

In addition, around a hundred endemisms have a wider distribution on the Iberian Peninsula.

The middle mountain

Forest formations

The acer groves (Acer granatense, A. monspessulanum) and gall oak groves (Quercus faginea) are scarcely represented due to strong anthropic action. They are found in the most humid areas of the Park, occupying the valleys and shady areas. The melojares (Quercus pyrenaica) of Sierra Nevada, although diminished by fires and abusive felling, are of great interest due to their ecological and chorological characteristics; they grow on acid soils and are well represented in the ravines on the north and south faces.

Holm oak groves are located between 1,300 and 1,700 m, although in some enclaves they can reach an altitude of 1,900 m. They grow on carbonate soils and are well represented in the ravines on the north and south faces. They grow both on carbonate soils and on acid rocks. The forest corresponds to a holm oak forest dominated by holm oak (Quercus rotundifolia) and, depending on the type of soil and altitude, shrubs such as junipers (Juniperus oxycedrus), blackthorn (Daphne gnidium), butcher’s broom (Ruscus aculeatus), barberry (Berberis hispanica) and hawthorn (Crataegus monogyna) are frequent on basic soils. In enclaves at lower altitudes, mastic (Pistacia lentiscus), wild olive (Olea europaea sylvestris) and sarsaparilla (Smilax aspera) are common. The siliceous holm oak grove is poor in species; in addition to the holm oak, there are junipers, blackthorn and honeysuckle (Lonicera etrusca).

The riparian vegetation develops along the banks of rivers and streams and is currently very degraded, and it is difficult to find riverside forests in a good state of conservation. Acidic soils are covered with alder groves (Alnus glutinosa), willow groves (Salix atrocinerea) and ash groves (Fraxinus angustifolia). In base-rich areas, riparian vegetation is mainly composed of elm (Ulmus minor), poplar (Populus alba) and willow (Salix spp.).

Fauna in the forests

These wooded areas are inhabited, on a more or less constant basis, by the green woodpecker (Picus viridis) and the short-toed treecreeper (Certhia brachydactyla). Alongside them, we can see some sedentary species such as the great tit (Parus major), the coal tit (Parus ater) and the blue tit (Parus caeruleus), which use the holes in the trunks to build their nests. Perched in the branches of the trees, we can see the scandalous jay (Garrulus glandarius) and the blackbird (Turdus merula). Typical spring visitors include the wren (Regulus ignicapillis), chiffchaff (Phylloscopus collybita), warblers (Sylvia atricapilla, S. communis) and chaffinch (Fringilla coelebs).

On dry land and in open areas, we can come across large specimens of ladder snake (Elaphe scalaris), some smooth snakes (Coronella girondica), ocellated lizards (Lacerta lepida) or the common toad (Bufo calamita).

Among the mammals, the fox (Vulpes vulpes) is frequent in these areas, although it sometimes goes out to hunt in the grasslands. The weasel (Mustela nivalis) disputes rabbits and hares with other mammals. The badger (Meles meles) and the genet (Genetta genetta), although common, are very difficult to see as they are nocturnal.

The Mediterranean high mountains

A wide variety of plant formations

Above 2,800 m (cryo-Mediterranean floor), where the soils are not very evolved and the climatic conditions are adverse, low grasslands with little cover (psicroxerophyllous grasslands) develop.

They are of great interest and constitute one of the most unique aspects of the Sierra Nevada. These grasslands are made up of a large number of endemic species (up to 40%): Arenaria imbricata, Artemisia granatensis, Festuca clementei, Hormatophylla purpurea.

The “cascajares” (rocky outcrops) are widespread and are home to a large number of species adapted to withstand these environments: Viola crassiuscula, Linaria glacialis. On rock faces, species that colonise crevices and ledges are frequent: Saxifraga nevadensis, Arabis alpina.

At the bottom of glacial cirques, there are “borreguiles”, hygrophytic grasslands which, as in the previous case, are rich in endemic species: Armeria splendens, Carex camposi, Plantago nivalis, Veronica turbicola.

Between 1,900-2,800 m (oromediterranean floor), pine and juniper forests develop. The vegetation is made up of tree and shrub species (Pinus sylvestris, Juniperus sabina, J. communis subsp. hemisphaerica, Prunus ramburii) and a thicket (Vella spinosa, Erinacea anthyllis, Bupleurum spinosum, Astragalus granatensis).

On moderately evolved soils, pyrenales and juniper groves develop, forming communities rich in fruit-bearing camelephytes and hemicryptophytes (Festuca indigesta, Arenaria imbricata). The endemic element is also abundant: Genista versicolor, Arenaria pungens, Potentilla nevadensis.

In calcareous areas at high altitude (Dornajo, headwaters of the river Dúrcal), and due to the scarcity of soil, a thicket with junipers and junipers develops, mixed with cushioned thyme. Species such as Sideritis carbonellis and Astragalus granatesis appear. Animal life in the high mountains

These are the domains of the Alpine accentor (Prunella collaris), the wheatear (Oenanthe oenanthe), the skylark (Alauda arvensis) and the black redstart (Phoenicurus ochrurus). Among the crags we can see the red rock thrush (Monticola saxatilis), which owes its name to the red colouring of the male’s breast which contrasts with the bluish black of his head.

At these heights we can see flocks of red-billed choughs (Pyrrhocorax pyrrhocorax pyrrhocorax) that set up their colonies in the escarpments and hollows. The golden eagle (Aquila chrysaetos) can be seen scouring the walls of the cliffs and crags, using these heights as a hunting ground. We can also spot griffon vultures (Gyps fulvus) and the common partridge (Alectoris rufa), which can climb up to 3,000 metres.

In autumn, the high mountains can be visited by the white-capped blackbird (Turdus torquatus), goldfinches (Carduelis carduelis) and groups of kestrels (Falco tinnunculus).

Among the mammals, the mountain goat (Capra pyrenaica) is the most emblematic species in the park. There are numerous specimens and they can easily be seen grazing in the sheepfolds of the high mountains. The common vole (Pytimis duodecimcostatus), more typical of humid areas at lower altitudes, and the snow vole (Chionomys nivalis), which sets up its galleries in rocky areas, as well as the animals they serve as prey, such as weasels (Mustela nivalis), also find shelter at these altitudes.

At this point, in addition to the botanical endemisms, there are more than eighty endemic insects. The conditions of the high mountains give these animals specific characteristics: they are generally black in colour, have a hard integument and have lost the ability to fly.