Lesvos has the perfect environment for thousands of native and migratory birds and amphibians. The most famous wetland area is located in Kalloni and serves as a refuge and breeding site for numerous rare and endangered bird species. About 134 species of birds have been recorded, among which are Eurasian coots, Eurasian stone-curlews, pied avocets, black storks, white storks, pink flamingos, common shags and swans, 45 dragonfly species and 530 bee species.
The wetland of Kalloni Bay includes the whole coastal area of the Gulf and a large number of inland wetlands: The salt pans of Kalloni and Polichnitos, the torrents of Tsiknia, Vouvaris, Mylopotamos, Ennia Kamares, Potamia, the Lagoon of Messon, etc. The coastal areas of Kalloni Bay are part of the NATURA 2000 protection network. The salt pans of Kalloni are inundated with many birds, such as herons, pelicans, flamingos etc.
The fauna and flora of the island is rich. The Carnivores found on the island of Lesvos are the ferret or "atsidi" (Martes foina), the weasel or "pontikonifi" (Mustela nivalis) and the fox (Vulpes vulpres). The most important mammal of Lesvos is the Persian squirrel (Sciurus anomalus), which is found nowhere else in Europe, apart from the island of Lesvos. Other animals on the island are the otter, the hedgehog (Erinaceus concolor) and the rabbit (Lepus capensis). There are also a lot of amphibia and reptile species.
Every year, the observation of birds (bird-watching) in the wetland of Kalloni Bay attracts many visitors, scientists and tourists. A large number of birdwatchers gather regularly here in early spring and late autumn.