All peculiarities of fauna and flora of the Meteliai Regional Park have been determined by a geographical position, distinctive climate and unique relief. The Dusia, Metelys and Obelija are magnificent lakes, sunken by one valley in the highland of Sūduva.
The greatest natural values of the park are the Dusia, Metelys and Obelija lakes being amongst the cleanest and the most suitable for a rest in the entire country. All of them have wide sand-banks which give a long-lasting shelter for the biggest order of migrating water birds in Dzūkija region.
The territory of the park is registered into list of territories internationally important for birds. The land has unique landscapes in the western part of the park with Teizai, Verstaminai, and Kalniškė ridges and hills formed by the latest glacier. Besides, there are hollows with wonderful vegetation as well as rich world of insects.
Leafy forests protected in the sanctuaries seem to be rather interesting, too. They grow together with sparse communities of hornbeams in the Girukė forest. In the Trakas forest, the only place in Lithuania, there remained a grove of sessile oak-tree.
European pond turtles are amongst the rarest animals of the country, which live in small water ponds near the Trakas forest, in the Juodabalė herpetological reserve. 192 species of birds, of which 130 species breed, are found in the Meteliai Regional Park. The great lakes of the park are the territory of European importance for migrating birds. Every year, during a seasonal migration, more than 10 thousand birds band here together. Every year flocks of great crested grebes (up to 2,000) as well as of coots (up to 15,000) are watched in the lakes. They are amongst the largest flocks of these birds in the Central Europe. Large flocks are formed by up to 4,000 tufted ducks, 1,000 golden-eyes, 600 red-crested pochards, 500 mallards, and up to 1,000 cormorants.