The pond of Biguglia, formerly called pond of Chiurlinu, is largest of the island: 1450 hectares, 11 kms length, and a width which reaches with its maximum 2,5 kms.
Skirting the sea, it pond on the four communes of Furiani, Biguglia, Borgo and Luciana, occupant in fact near total of the littoral of the plain of Marana.
The exceptional character of this natural site, is not limited to its landscape quality. Rescencement of the avifauna, regularly observed on the pond makes state of more than 120 species of birds, including 19 nicheuses species, 68 estivantes and 53 wintering. Four species winter abundantly on the water level (Foulque macroule, Fuligule tufted duck, Fuligule milouinan and large Cormorant), while various species of Central and septentrional Europe gain the roselières for a stay winter (fishing Martin, Reed bunting, Mésange rémiz or Lusciniole with moustache).
The mudholes of the north of the pond, they, are very attended by migrating water birds. Observations carried out for soon two decades have shown that the majority of limicolous, the large waders and of laridés (Gulls, Seagulls, Stemes, and Guifettes) of Europe make stopover there. True wonder of nature, the natural reserve of Biguglia is characterized finally by an astonishing floristic richness. One observes a large variety of species of which some very rare. It arises from the botanical inventory that about thirty species are rare or very rare, whose some deserve a detailed attention. The international recognition of the exceptional character of the pond, on which the classification in natural reserve is added, constitutes a considerable projection in the protection of such a site.