Dvina Bay streams. There are many small islands in the Dvina Bay as well, the biggest being Mudyug Island. A national park, Onezhskoye Pomorye National Park, was open on the Onega Peninsula on 26 February 2013. The Dvina Bay is limited by the Onega Peninsula from the west. At the eastern side, the shore steeply rises to a plateau (White Sea - Kuloy Plateau) which drains east into the Soyana, a major tributary of the Kuloy. The Onega Bay shore is often referred to as "Letny Bereg" (Summer Coast), and the eastern shore of the bay is "Zimny Bereg" (Winter Coast). The
Arkhangelsk Oblast distinct population of polar bears associated with the Barents Sea area. Almost all of the area of the Oblast belongs to the basin of the Arctic Ocean, with the major rivers being (west to east) Onega River, Northern Dvina River (with the major tributaries the Vychegda, the Vaga, and the Pinega), Kuloy River, Mezen River, and Pechora River (Shapkina River being a major tributary). A minor area in the west of the Oblast, most notably the basin of the Ileksa River, drains into the Lake Onega and eventually to the Baltic Sea. A very minor area in Kargopolsky District in