Remote sensing applications for studying coastal haul-out sites of the Baikal seal Pusa sibirica Gm.

   Using remote sensing methods — specifically camera traps, unmanned aerial vehicles(UAVs), and video systems, which represent the least intrusive techniques for studying wild seal populations — we investigated the behavioral responses of the Baikal seal (Pusa sibirica Gm.) to unusual ice conditions during the final stage of ice breakup in 2024. The timing of seal emergence onto the coastal rookeries of the Ushkany Islands (Lake Baikal) coincided with the disappearance of floating ice in the northern part of the lake. The mass arrival of animals began on June 7 and lasted for four days. Using the northern rookery of Dolgy Island as an example, we describe the temporal dynamics of seal arrival and abundance. A census of the total number of seals on the rookeries (BLS) revealed that thousands of individuals simultaneously occupy the islands. The largest numbers are typically observed on Krugly Island, with fewer on Dolgy Island. In some cases, animals may move between islands – for instance, from Dolgy Island, which experiences disturbance from tourist activity, to neighboring islands. However, the overall pattern of rookery occupation varies from year to year. During summer (July–August), the total number of Baikal seals on the islands is generally lower than during the initial establishment of rookeries (early June, occasionally late May), although numbers may still reach several thousand. The presence of a negative impact of anthropogenic factors on animal behavior is noted. To develop appropriate environmental management measures, we propose expanding research on the effects of anthropogenic factors on the Baikal seal.

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