According to the definition of the International Union for Conservation of Nature and Natural Resources (IUCN), wetlands on Earth are areas that are flooded or saturated with water, artificial or natural, permanently or temporarily flooded with standing, sitting or running water. These areas include areas where water is the predominant element, such as swamps, wetlands, peatlands, estuaries, sea branches and lagoons, lakes, rivers and artificial reservoirs with a depth of more than six meters. Considering the importance of these territories and with the deep conviction that the preservation of their flora and fauna can be ensured by combining long-term national policy with coordinated international action, the scientific community reacted to the encroachments and unreasonable attitude to them by concluding 02.02. 1971 of the Convention on wetlands of international importance, especially as waterfowl habitats, known to the general public as the Ramsar Convention. The main objectives of this document are to manage wetlands as sites of great economic, cultural, scientific and conservation value, to avoid damage and loss and to preserve them through prudent use, i.e. through their continuous development. The object of study in the present work is the biological diversity, in particular the avifauna of some of the internationally important wetlands in the border areas between Bulgaria, Greece, the Republic of North Macedonia and Albania in view of the opportunities they offer for the development of some forms of alternative types of tourism.