Birds:
Zhrebchevo Reservoir is considered to be a site with international importance for the wintering waterfowl. Every year over 20,000 waterfowl of 33species concentrate there. The reservoir, together with the fishponds supports 77 bird species – mainly wintering ones, 23 of which are listed in the Red Data Book for Bulgaria (1985). Of the birds occurring there 62 species are of European conservation concern (SPEC) (BirdLife International, 2004), 3 of them being listed in category SPEC 1 as globally threatened, 5 in SPEC 2 and 18 in SPEC 3 as species threatened in Europe. The area provides suitable habitats for 20 species, included in Annex 2 of the Biodiversity Act, which need special conservation measures, of which 16 are listed also in Annex I of the Birds Directive. The reservoir, together with the fishponds, is of international importance for the wintering Common Teal Anas crecca, Mallard Anas platyrhynchos, White-fronted Goose Anser albifrons and Great White Egret Egretta alba. It is one of the few places in the country where the globally threatened Red-Breasted Goose Branta ruficollis overwinter inland, far from the coastal areas. The White-tailed Eagle Haliaeetus albicilla regularly occurs in the area during the winter. During the breeding season the area is of a European Union importance for the Marsh Harrier Circus aeruginosus.