Porphyrio porphyrio camel or chicken-sultana, symbol of the Ria Formosa Natural Park (® Enri Sastre).
The diversity of vegetal communities corresponds to an abundance of fauna, which is one of the outstanding aspects of the Ria Formosa, with particular emphasis on birds, which include many species considered endangered, one of the main interests of nature conservation.
Many species of migratory waterbirds from northern Europe spend winter here or use the Ria as a stopover point on their route to more southern areas. Among the most relevant wintering species are the Anas platyrhynchos, Anas penelope, Anas clypeata, Anas crecca, Antarctica, and Aythya ferina, Charadrius alexandrinus, Charadrius hiaticula, Gray-billed Plover Pluvialis squatarola, Limosa lapponica fuselage, Milherango or Thrush-billed Thrush, Limosa limosa, the tortoise-whip -real Numenius arquata, the tailor Recurvirostra avosetta, the long-legged or stilt Himantopus himantopus, the small-breasted Calidris minuta and the common-breasted or black-bellied Calidris alpina.
Worthy of note is the Camão or Galinha-sultana Porphyrio porphyrio, an emblematic species of the Park, and due to the growing protection and study of this species, the population of this species has increased in recent years.
Also worthy of mention are the Egretta garzetta Egret, the Spoonbill Platalea leucorodia also nesting in a few years; and populations of White Stork Ciconia ciconia. The population of Sternula albifrons, a declining species in Europe, nest in the dunes and salt flats of the Ria Formosa, represents 40% of the total population of Portugal.
Birds of prey are infrequent, but during times of migration and in winter they are hunting around the area, such as the blue-eyed Circus Turtle and the Circus Pygargus; the buteo or round-winged eagle Buteo buteo and several hawks such as the peregrine falcon Falco peregrinus and the common kestrel Falco tinnunculus. As well as some nocturnal preys the asio nabal Asio flammeus, the Tyto alba-owl-towers and the white-tailed owl Strix aluco.
The importance of the estuary in the life cycle of numerous species of fish, molluscs and crustaceans, especially as a breeding and feeding area, should be emphasized. The benthic communities, varying from the distinct marine species to the lagoon system, present extremely numerous populations, some of them of economic interest, such as the Ruditapes decussatus, the cockle Cerastoderma edule and the Ensis siliqua. Of the ichthyofauna are identified 65 species, which are divided into sedentary, occasional and migratory-colonizing; of which the most economical are Sparus aurata, Diplodus sargus, Dicentratus labrax, Solea senegalensis, and Anguilla anguilla eel.
In reptiles, the Chamaeleo chamaeleon chameleon, a species threatened with extinction, is reported to be confined to the Algarve’s Sotavento coast, continental pine forests and barrier islands.
Of the existing mammals we can highlight the Lutra lutra otter, the sucker Herpestes ichneumon, the Genetta genetta genetta, the Martins foley weasel, the badger Meles meles and the fox Vulpes vulpes.