The city of Bourgas lies at the centre of a complex of extensive wetland sites that form one of Europe's richest bird areas. Together the Bourgas lakes harbor 340 of the 400 bird species, recorded in the country. The biggest attractions of the Bourgas wetlands are the huge flocks of Dalmatian and White Pelicans resident there and the thousands of White-headed Ducks regularly wintering in Vaya lake.
Lake Atanassovsko is a shallow saline lagoon with traditional saltpans still preserved. It is of major importance for the huge numbers of birds, including Avocet, Black-winged Stilt, Broad-billed and Curlew Sandpipers, Marsh Sandpiper, Kentish Plover, Slender-billed and Mediterranean Gulls, Gull-billed Tern and many other waterfowl and wader species. The numbers of soaring birds following the Black Sea coastal flyway in spring and autumn can rival those at the Bosphoros or Gibraltar - endless flocks of thousands of storks, pelicans, cranes and raptors pass overhead. The lush vegetation embracing the freshwater lakes of Mandra and Vaya and the surrounding reedbeds swarm with life - the air resounds with the song of Savi's and Cetti's Warblers whilst Golden Orioles flash trough waterside poplars, and Penduline Tits attend their fantastic hanging nests. Watching the life in the lakes  inevitably creates the impression that they are created for the birds - Glossy Ibis, Spoonbill Pygmy Cormorant, Squacco, Night and Purple Herons, White-winged Black Terns and many, many others.