The wintering populations of 5 species of water-loving birds (greater white-fronted goose, grey lag goose, red – breasted goose, whooping swan, mallard) and the numbers of another three species (white stork, shoveller and small cormorant) during migration have contributed to the international recognition of the wet zone as a Ramsar site. The lakes of Shabla and the neighbouring Lake of Durankulak form together the most numerous up-to-date wintering area for the nearly extinct greater white-fronted goose in world scale.

The protected territory is situated on the Via Pontica migration route and provides favourable conditions for feeding and rest of series of migratory species of birds.
 

Three of them- small cormorant, white stork and shoveller – cover the Ramsar quantitative criteria. The protected area is of international significance for the nesting of Lesser grey shrike, as well as of extreme importance at national level for the nesting of marsh harrier, snowy plover and the paddyfield warblerе. The lakes have a serious potential for the preservation of the wild carp and the sand dunes are a shelter of the numerous and stable population of the Eastern spadefoot. The protected territory is of great significance and for the otter preservation.