The South of Portugal, which includes the Alentejo and the Algarve regions, is the birdwatching “ex libris” of the country’s mainland.  Together these regions cover most of the bird species in the country.

The Alentejo is known for its extensive flat agricultural plains and steppes. Castro Verde area is the main hotspot in this region. This is the home of Great Bustard, Little Bustard, Common Crane, Red Kite, Montagu's Harrier, Black-winged Kite, Lesser Kestrel, Stone Curlew, Black-bellied Sandgrouse, Great Spotted Cuckoo, European Roller, Calandra, Short-toed and Thekla Larks, Tawny Pipit, Rufous-tailed Scrub Robin, among others.

The Algarve is known by its wonderful wetlands and diverse coastline. About 395 bird species can be observed in the region, this means that around 95% of all bird species observed in Portugal can be seen in the region in a certain time of the year.

Ria Formosa Natural Park is a place any birdwatcher can’t miss! It is one of Europe’s most important protected wetlands and it is characterized by coastal sandy dunes that protect a lagoon forming a variety of natural habitats: barrier islands, mudflats, dunes, salt marshes, freshwater ponds and brackish water, waterways, forests and agricultural areas. Aquatic birds are a group well represented with most species from the orders Anseriformes, Podicipediformes, Gruiformes, Ciconiiformes and Charadriiformes. More than a hundred species from this group are present in the region. In the park is possible to spot: Little Bittern, Purple Heron, several species of grebes and ducks, Purple Swamphen (the symbol of the park), Black-winged Stilt, Kentish Plover, Avocet, Azure-winged Magpie, Eurasian Hoopoe, and Bee-eater.

Sagres, in the west-end of the Algarve, is a well-known place for birdwatching especially during Autumn migration. Birds passing by on migration includes seabirds, raptors, and passerines. On other seasons birdwatching here is also worthy. Common raptor species in the area are Griffon Vulture, Short-toed and Booted Eagles, Common Buzzard, Black Kites, Egyptian Vultures and Peregrine Falcons.

Another mandatory site is Lagoa dos Salgados, a large brackish coastal lagoon that is protected from the ocean by the large adjacent dune system of the Praia Grande beach. This spot is a breeding area for Ferruginous Duck and a favourite haunt and nesting place for the Purple Swamphens, the Purple Herons, and the Little Bitterns. Other herons, Spoonbills and Greater Flamingos are also often present.

Right by the Spanish border, is Castro Marim Nature Reserve. The area is characterized by numerous canals, saline flats, and salt pans, which are home to more than 200 bird species though out the year. During a day walking in this area, it is possible to watch easily more than 60 species. Some breeding species in the area are the Pied Avocet, Black-winged Stilt, Mediterranean Short-toed Lark (only place in Portugal where it occurs) and the Great Spotted Cuckoo.