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
Novaya Zemlya Russians knew of Novaya Zemlya from the 11th century, when hunters from Novgorod visited the area. For western Europeans, the search for the Northern Sea Route in the 16th century led to its exploration. The first visit from a west European was by Hugh Willoughby in 1553. Dutch explorer Willem Barentsz reached the west coast of Novaya Zemlya in 1594, and in a subsequent expedition of 1596 rounded the Northern point and wintered on the Northeast coast. (Barentsz died during the expedition, and may have been buried on the Northern island.) During a later voyage by Fyodor Litke in 1821–1824,