Lake Undozero Lake Undozero Lake Undozero () is a freshwater lake, located in the west of Plesetsky District of Arkhangelsk Oblast in Russia. It is one of the biggest lakes in Arkhangelsk Oblast and the second biggest one in Plesetsky District. The area of the lake is , and the area of its basin is . Lake Undozero is the source of the Undosha River, which belongs to the river basin the Onega River and thus to the White Sea basin. The lake has a sophisticated shape and contains a number of islands. The source of the Undosha is in the south-western
Lake Onega Common mammals include elks, brown bears, wolves, red foxes, European hares, blue hares, red squirrels, lynxes, pine martens, European badgers, as well as American muskrats and minks which were introduced to the area in the early 20th century. About 200 bird species from 15 families have been observed in the lake basin. Lake Onega features a large variety of fish and water invertebrates, including relicts of the glacial period such as lamprey. There are about 47 fish species from 13 families; they include sturgeon, landlocked salmon, brown trout, European smelt, grayling, roaches, Crucian carp, whitefishes, char, pike, European cisco, common