The Site is located in the Sofia Region of north-western Madagascar. It is composed of blocks and fragments of dense mountainous tropical rainforest, grasslands, marshes and swamps, lakes, rivers and streams. The Site hosts a complex of ecosystems and provides refuge habitat for the survival and reproduction of many endemic and endangered species. 106 species of birds have been inventoried there. Waterbirds include the critically endangered Madagascar pochard (Aythya innotata) which was discovered in 2006 on this site only, the endangered Meller’s duck (Anas melleri) and Malagasy pond heron (Ardeola idae), and the vulnerable Madagascar grebe (Tachybaptus pelzelnii), Madagascar rail (Rallus madagascariensis). Land birds include the endangered Madagascar serpent-eagle (Eutriorchis astur) and the vulnerable red owl (Tyto soumagnei), Madagascar marsh-harrier (Circus macrosceles), red-tailed Newtonia (Newtonia fanovanae) and dusky greenbul (Phyllastrephus tenebrosus). In addition, seven species of lemur have been recorded. The Site and the river basin of which it is part also support irrigated rice production. Bemanevika’s lacustrine and swampy ecosystems maintain the water regimes of the area and ensure the regulation of the microclimate.