Lake Trasimeno – Italy

Background Lake Trasimeno

With its 126 sq. km. surface, Lago di Trasimeno is Italy’s fourth largest lake. The shallow lake with a maximum depth of 6 m is located in Umbria, northwest of Perugia at an altitude of 257 metres above sea level. As the lake has no natural inflow and outlet, it is fed solely by rain water. Average annual precipitation amounts to 723 mm.

In the past, several attempts were made to get the fluctuating water levels under control. At Roman times a subterranean outflow channel was constructed near San Savino which silted up over the years. The draining of the lake was a frequently discussed topic in order to fight against malaria and to gain new farmland. In 1898 a subterranean channel to the Caina torrent was built to protect the shore from inundations. The low water level in summer leads to algae growth.

In the lake are three islands: Isola Maggiore covers an area of 23,2 hectares and is inhabited. Isola Minore (6,5 hectares) is uninhabited. Isola Polvese has a surface of 64,4 hectares, and is owned by the provincial administration. It is a recognised nature reserve. On the islands grow olives and pines.

The shore is sparsely inhabited. The area is partly covered with reed; water lilies and oak forests are also found along the shores. In the traditional cultural landscapes corn, maize and tobacco are cultivated. A lot of marsh plants such as White Water Lily, Common Marsh-bedstraw, Yellow Iris, Star Duckweed, Spiny Naiad as well as Lakeshore Bulrush are found in the area.

The fish abundance is an important source of income for lake residents. Among the fish species Tench, Eel, Carp, Pike and Perch are found. Rare amphibian such as Alpine Crested Newt and reptiles such as Dice Snake live in and at Lake Trasimeno.

Many migratory birds rest at Lake Trasimene. Among them are Squacco Heron, Purple Heron, Little Bittern, Kingfisher, Bittern, Wigeon, Mallard, Tufted Duck, Ferruginous Duck, Great Crested Grebe. Occurring raptors are Short-toed Snake Eagle, Osprey and Eagle Owl.