Permanent mammal species include ringed seal, bearded seal, Harp Seal, walrus, collared lemming, Arctic fox, reindeer, wolf, ermine, Arctic hare and polar bear. The beluga whale visits the region seasonally. There are several dozens species of birds. Some belong to permanent (tundra) species, such as snow bunting, purple sandpiper, Snowy Owl and brent goose. Others make large colonies on the islands and sea shores. These include little auk, Black-legged Kittiwake, black guillemot, ivory gull, "uria", "charadriiformes" and glaucous gull. Other bird species are skua, sterna, Northern Fulmar, Ivory Gull, Glaucous Gull, Ross's Gull, Long-tailed Duck, eider, loon and Willow Grouse. There are 39 fish species, mostly typical of braskish environment. The major ones are grayling and "Coregonus" (whitefishes), such as muksun, broad whitefish and omul. Also common are sardine, Arctic cisco, Bering cisco, polar smelt, saffron cod, polar cod, flounder and arctic char and inconnu.