Franz Josef Land and snow bunting. Some ivory gulls, little auks and Brünnich's guillemots opt to spend the winter on the islands. The polar bear population of Franz Josef Land lies within the Barents Sea subpopulation, which also includes polar bears inhabiting Svalbard and the western coast of Novaya Zemlya. In 2004, the Barents Sea subpopulation was estimated at 2,650. There is also a population of Arctic fox, which typically have their territories near seabird habitats. Being declared as a marine mammal sanctuary, the island has rich biodiversity of rare marine mammals. Three species of seals habit the archipelago. Harp seal is the
Severnaya Zemlya of the Severnaya Zemlya group and is separated from Komsomolets Island by the Yuny Strait. Pioneer island measures in area. This island houses the Pioneer Glacier. Thelodonti fossils from the Upper Silurian have been found in the island. Off Pioneer Island's southwestern end lies Krupskoy Island. This is a fairly large island, over in length and about in width. The sound that separates it from Pioneer is only in width. This island should not be confused with Pioneer Island in Canada (). Schmidt Island, measuring , is located at the far northwestern end of the archipelago. This island is quite