The need for the preservation of the monk seal was the motive behind the formation of the Marine Park. Definite attempts were started in 1983 with the signing of an agreement between the Ministry of Environmental Planning and Public Works and the EEC resulting in the research for the estimation of the environmental value of the area.
The area consisting of the park is ideal and contains a natural Mediterranean ecosystem extremely well balanced. The caves on the land, the stalagmites, the stalactites, the beaches and the underwater caves not only have an aesthetic value but a biological one as well, The geological and biological evolution of the Northern Sporades have their origins in the prehistoric times when the existing islands formed a peninsula joined with Pelion.
The largest known existing population of the monk seal (monachus-monachus) lives in the Northern Sporades and is being threatened with extinction. The rich flora and fauna on the deserted islands is ideal for the dietary demands of the seal and provide the proper conditions for their reproduction. The deserted islands to the northeast of Alonissos are a paradise full of wildlife.
The island of Gioura is a botanical paradise for rare plants and has a unique species of wild goat. On Skantzoura and her steep cliffs the falcon finds refuge along with the rare Aegean sea gull, isolated reptile populations of great interest also live on these deserted islands. The island Piperi is the natural refuge of the monk seal. Approaching the island is strictly prohibited as this is where the seals reproduce. Only research teams with a specific license are allowed to approach.