The protected area of the Bolle di Magadino is situated where the rivers Verzasca and Ticino form their deltas, flowing in the northern basin of Lake Maggiore. The meeting of water and land, together with the mixing of different soil types, from gravel to sand, create a wide range of ecosystems on a small area (little more than 300 hectares).
Such a diversity of habitats results in a diversity of ecological niches, where plant and animal species live, which adapted themselves to very specific living conditions. Over 3000 different species have been recorded so far within the reserve, a big number if compared to its surface. Species living in water and marsh habitats are the most specialized, and they require greater responsibility for their conservation: one quarter of the species living in the reserve is under threat of extinction. Today the landscape is dominated by water, reed beds (Phragmites australis) and woods of white willow (Salix alba) and English oak (Quercus robur).
In Switzerland there are no longer delta ecosystems in their natural state. The Bolle di Magadino, located south of the Alps, are one of the last examples of delta where at least part of the natural habitats were preserved: this is why the Bolle were included in 1982 in the list of wetlands of international importance according to the Ramsar Convention, particularly for their relevance as a waterbirds habitat.