The main attraction of the animal world of the Ushkany Islands is the Baikal seal – the nerpa. The rocky shores of the islands are considered a favorite rookery for seals – on Tonkiy Island alone, up to 2 thousand seals are taken to the rookery at the same time. The fauna is different from the mainland fauna. One of the most unique phenomena on the islands is the unusual number of anthills. On the Big Island alone there are several thousand anthills – their density reaches a record 20 anthills per 0.01 km².

The Big Island has the best preserved “primordial” forest – most of the island is covered with tall larches and pines with an undergrowth of Daurian rhododendron blooming with purple inflorescences. Here, many plants have features that can only be found on the Ushkany Islands. On the Big Island, for example, you can find specimens of Dahurian larch with a bottle-shaped thickening of the bark at the base of the trunk, birch with black bark and trees with flag-shaped crowns. In summer, blooming seaweed is often found on the steep shores of the islands, and brown lichen is found on the coastal rocks. The islands themselves are formed mainly from crystalline limestones.