Па-беларуску, калі ласка
Asveja Lake and Mire Complex

Location: Vicebsk Region, Vjarhnedzvinsk District

Coordinates: 56°06 N 28°01 E

Area: 22,600 ha

National Conservation Status:A national landscape zakaznik was established in 2000 on the basis of the former hunting zakaznik.

International Conservation Status:An IBA was established in 1998 (code BY001, criteria В2, В3).Ramsar site (criterion 1а).

The site is a large complex of lakes, forests, and transition and bog mires. The core of the IBA is Asveja Lake which defines much of the hydrology and climate of northern Belarus. The surface of this largest Belarusian eutrophic lake becomes rapidly overgrown with surface vegetation. Most of the IBA is covered by bogs and transition mires, mixed with pinewoods, birch, and black alder forests. A few mineral islands are scattered across the mires. Forest vegetation covers about 30% of the IBA’s overall area, shrubs 4%, meadows 6%. There are few fens.

The IBA pertains to the basin of the Zahodniaja Dzvina river and is part of the Svolna river sub-basin. The hydrographic network is well developed and includes lakes, rivers and drainage canals and ditches. Lake Asveja is the most important element of the network. It covers 47.95 km2, making it the second largest natural lake in Belarus. It is a shallow lake, with an average depth of 2 m. Several small rivers and canals flow into the lake, but the main part of its recharge comes from precipitation. The lake had become intensely overgrown with vegetation over the last several years, losing its value as a fishing lake and an important place for waterbirds. One of the causes of the overgrowth is the declining water level in the lake: a substantial amount of water flows out of it through the Degtiariovka Canal. A regulated sluice, an embankment and a bypass supply ditch were constructed on the canal to regulate the water level in the lake, but these are not functioning properly. Peat extraction close to the lake is also lowering the water level.

A total of 164 breeding bird species have been recorded, including 36 species listed in the National Red Data Book. The most important of them are: Bittern Botaurus stellaris(40-60  males), Golden Eagle Aquila chrysaetos(1 pair), Osprey Pandion haliaetus(3 pairs), Black Grouse (up to 150 males). 

Asveja Lake is one of the largest breeding and post-breeding grounds in Belarus for numerous game waterbird species: Mallard Anas platyrhynchos, Pochard Aythya ferina, and Coot Fulica atra. The Lake and the surrounding areas have a high value for large concentrations of waterbirds during spring and autumn migration.

A total of 16 National Red Data Book plant species have been recorded. Some rare plants include hybrids of Black Alder and Grey Alder (Alnus glutinosa andA. incana), tall-stalk forms of Betula pendula var. carelica,a large population of Yellow Pondlily Nuphar pumila, as well as a rare insectivorous plant Waterwheel Aldrovanda vesiculosa.

Four mammal species found on the site are listed in the National Red Data Book of Belarus.