Vizír National Nature Monument

The Vizír NNM lies 3 kilometres west of the town of Chlum u Třeboně in the Jihočeský kraj – South Bohemian Region and in the central part of the Třeboňsko PLA. The monument was declared in 1987 on an area of 10.22 hectares. The subject of the protection is the populations of carnivorous plants which grow in the bays around a fishpond. In the past the vegetation was often damaged by dredging works in the fishpond and the use of herbicides.
 
All that is left of the formerly contiguous growths of the water lily Nymphaea candida are scattered individual plants around the fringes of growths of bottle sedge (Carex rostrata) and common cotton-grass (Eriophorum angustifolium). The pale bladderwort (Utricularia ochroleuca) has survived in the shallow fishpond water and the peaty banks of the bays have been regenerated by the white beak-sedge (Rhynchospora alba). After the reclamation works the carnivorous round-leaved sundew (Drosera rotundifolia) and oblong-leaved sundew (Drosera intermedia) can be found in the moss carpets, whereas the cranberry Oxycoccus palustris and the star sedge (Carex echinata) grow towards the forested area. In the semi-shaded areas under the trees with growths of moor-grass (Molinia arundinacea) we can also find shrubs such as heather (Calluna vulgaris), labrador tea (Ledum palustre) and bog whortleberry (Vaccinium uliginosum).
 
The fishpond is currently the only locality in the Czech Republic for the diving beetle Graphoderus bilinaetus. Several amphibian species regularly breed in the fishpond, including the common spadefoot (Pelobates fuscus), moor frog (Rana arvalis) and pool frog (Rana lessonae). Grass snakes (Natrix natrix) are commonly seen around the fishpond.
 
Goldeneye ducks (Bucephala clangula) nest in the oak trees on the fishpond dam and in nesting boxes. The pond also provides food for a range of waterbirds such as the grey heron (Arderea cinerea) and the black stork (Ciconia nigra). Otters (Lutra lutra) also live and hunt in the area.
 
The fishpond is in private ownership and the fish-farming is carried out in a less intensive way. The locality is accessible along a forest track which runs along the dam wall.