A wide range of diverse plant communities can be found in the Mechelińskie Łąki Reserve, creating a characteristic zonal system as one moves from the shoreline of the bay towards the interior of the land. Different zones can be observed, including the beach, dune grasslands, saline and halophytic meadows, and reed swamps. Among these communities, the most valuable ones are those formed under the influence of the salty waters of the bay, such as halophytic and półyhalophytic communities dominated by salt-tolerant plants. Among the most valuable species of flora occurring in the reserve are seaside pennywort and saltmarshes. Mechelińskie Łąki is an important location for valuable fauna species. It is a nesting site for rare water and wetland bird species, as well as a resting place for birds during migration. Rare bird species found in the reserve include the white-fronted tern, river tern, osprey, common ringed and little ringed plovers, crane, bittern, and bearded reedling. The Mechelińskie Łąki Reserve is not only a habitat for birds but also a place for tailless amphibians. The reserve is home to most of the national amphibian species, including all three types of toads. A particularly valuable species found here is the rare stripeless tree frog, which is rarely seen in Poland.