The Importance of Coastal Hauling Grounds in the Life of the Baikal Seal (Pusa sibirica Gmelin 1788, Pinnipedia): 3. Utilization of Coastal Hauling Grounds by the Baikal Seal on Tonkii Island (Tonkii Ushkan Islet), Ushkan Islands, Lake Baikal, Based on Video Observations

— Based on an analysis of unique video materials recorded over four seasons in 2012, 2014, 2018, and 2019 on one of the main hauling grounds of the Baikal seal Pusa sibirica on Tonkii Ushkan Islet (Lake Baikal), original information is reported on its utilization patterns in summer and fall. The seal is shown to use the shore intensively for 5–6 months annually from May to October, sometimes staying until early November. This paper describes the daily and seasonal dynamics of utilization of the hauling grounds and estimates their ecological carrying capacity (approximately 300 individuals). Staying ashore is a vital necessity to a large part of the population, as each season thousands individuals of both sexes and different ages appear to pass through the hauling ground areas. The main purpose of the hauling grounds along with relaxation is the need to complete molting, since molting individuals account for 40–60% of the animals on the hauling grounds. This is due to climate change in the region; in particular, the altered ice regime, which prevents the animals from completing molting on floating ice. Numerous animals in haul-outs display pathological conditions (scars, sores, and recent injuries), mostly on the skin and hair cover. The main factor of animal fright is human disturbance, due to which the Baikal seal leaves the shore daily.