The Ribeira de Quarteira is included in the list of Sites of Community Importance, an area classified as a Natura 2000 Network. It is an area with unique characteristics in the region, bringing together a set of natural, cultural and historical values of recognised national and international importance, including the presence of endemic, rare or endangered floral species in the national territory.
With over 300 identified species of flora, several plants restricted to the Algarve region stand out, such as the big-headed thyme (Thymus lotocephalus), a species classified as Near Threatened (NT) or the Centaurea occasus, classified as Vulnerable (VU). Also noteworthy are the species Narcissus willkommii (EN), globularia (Globularia alypum) and Helianthemum cinereum subsp rotundifolium, whose distribution is currently restricted to the Ribeira de Quarteira, with the latter two classified as Critically Endangered (CR). It is also common to find esparto grass (Stipa tenacissima), a plant of great importance from a regional ethnobotanical point of view, as it was used to produce mats and other products. It is also an emblematic species because in Portugal it only occurs in the Barrocal Algarvio region.
This site also includes a small stretch along the Quarteira river in excellent condition, inviting you to take pleasant walks among tamarisks (Tamarix africana), oleanders (Nerium oleander) and ash trees (Fraxinus angustifola), elements that enrich the landscape and serve as protection and ecological corridors for many species, particularly birds (e.g. Phylloscopus collybita) and bat species.
On the adjacent slopes, where Mediterranean shrubs predominate, there is a change in the floral composition with kermes oak (Quercus coccifera), dwarf palm (Chamaerops humilis) and various aromatic plants (thyme), which provide shelter and food for several species of passerines (e.g. Erinaceus europaeus).