The San Giuliano regional reserve is a protected natural area located in the municipalities of Matera, Miglionico and Grottole. The reserve occupies an area of 1000 hectares. The history of the Oasi San Giuliano Oriented Nature Reserve is linked to the birth of the homonymous artificial reservoir created for irrigation purposes by the damming of the Bradano river in the years between 1950 and 1957 thanks to the economic aid program of the Marshall Plan. The presence of the lake has attracted numerous species of aquatic birds right from the start, making initiatives aimed at protecting the area necessary. Thus in 1976 the lake of San Giuliano became an oasis for the protection of fauna, and the following year the landscape restriction was affixed.
In 1989, the WWF Italy obtained, through an agreement with the Consorzio di Bonifica di Bradano and Metaponto, concessionaire of the area, the naturalistic management, establishing an oasis.[2] Since 1991, the section of the Bradano ravine located downstream of the reservoir has become part of the Murgia Materana Park and therefore a UNESCO World Heritage Site. In August 2006, a fossil skeleton of a whale dating back to the Pleistocene,[4][5][6] about 27 meters long, was found on the shores of the lake. In the following years the fossil was recovered and transferred to a laboratory of the Superintendence for the historical, artistic and demo-anthropological heritage, waiting to be exhibited in the Domenico Ridola national archaeological museum in Matera [7], the last finds were collected in 2011, and are found locked up in wooden crates placed in the garden of the Museum, by the Superintendency for cultural heritage, waiting for them to be given an exhibition arrangement with a timeline not yet defined. The presence of birdlife within the reserve is of great importance especially during wintering and migrations. There are in fact about 180 species of birds, many of which are classified as rare species. Among the aquatic species there are gray herons, egrets, grebes, coots. In winter, the great white heron, the cormorant, the pochard, the widgeon, the shelduck, the wild goose and the rare ferruginous duck appear. Among the birds of prey, the red kite, the black kite, the buzzard, some specimens of osprey and some Egyptian vultures are common. Among the passerines it is worth mentioning the pendulum, symbol of the WWF oasis. Finally, among the mammals there are porcupines, badgers, wild cats and stone martens, as well as some specimens of otters.