The Srebarna Nature Reserve is a freshwater lake adjacent to the Danube and extending over 600 ha. It is the breeding ground of almost 100 species of birds, many of which are rare or endangered. Some 80 other bird species migrate and seek refuge there every winter. Among the most interesting bird species are the Dalmatian pelican, great egret, night heron, purple heron, glossy ibis and white spoonbill.
The Srebarna Nature Reserve is a freshwater lake adjacent to the Danube and extending over 600 ha. It is the breeding ground of almost 100 species of bird, many of which are rare or endangered. Some 80 other bird species migrate and seek refuge there every winter. Among the most interesting bird species are the Dalmatian pelican, great egret, night heron, purple heron, glossy ibis and white spoonbill, white-tailed eagle, little cormorant.
The reserve was set up primarily to protect the rich diversity of wildfowl, the bird species represent half of the Bulgarian avifauna. Species found in Srebarna include mute swan, a variety of geese and ducks, red-necked grebe, two of the three European species of marsh tern, and bearded tit. Otter is occasionally found in the reserve. White-fronted goose, red-breasted goose and blue throat have become established as wintering species.
Some 67 plant species can be found in Srebarna Nature Reserve, including water lily and a number of rare marsh plants. Reeds occupy two-thirds of the reserve and form a thick barrier around the lake. They form reed-mace islands which birds use for nesting.
This freshwater lake is situated on the flood plain of the River Danube, to which it was connected until 1949. The disconnection prevented annual flooding and the level of lake falls 1 m per year. However, the lake was reconnected by canal in 1978 with the Danube to prevent water levels from becoming too low and to restore the lake's fish population.
The reserve is affected by a rapid and abnormal development of succession processes due to annual sedimentation of large reed-mace vegetation in the reserve, as well as the insufficient water influence of the Danube. Consequently, the reed-mace islands are extended and increased in thickness so that wild boars, foxes and jackals now pose a threat to both individual birds nests and colonies. A series of upstream interferences, including the Iron Gate Dam, have permanently altered the natural hydrology of the Danube River in this region and that of Srebarna.
The area was declared a wildfowl refuge in 1942 and established as a nature reserve by the Ministry of Agriculture and Foods on 20 September 1948, Decree No. 2-11-931. It was accepted as a World Heritage site on 7 March 1974, as a Ramsar site on 24 September 1975 and as a biosphere reserve in January 1977.