Rausu Wildlife: Ocean and River
The waters of the Nemuro Strait between Rausu and Kunashiri Island are nutrient-rich and support a wealth of marine life. This thriving marine environment is due to ice floes which flood the strait with fresh oxygen-rich water each winter. An explosion of plankton under this drift ice sparks a marine lifecycle from tiny fairy shrimp to enormous sperm whales. Depending on the season, visitors to Rausu can watch whales, Steller’s sea lions, dolphins, porpoises, seals, and salmon from observation decks or boat tours.
Whales
Whales are nomadic creatures; food sources dictate their travel paths. The Nemuro Strait offers a reliable supply of food and deep waters, meaning whales are present in the strait for most of the year. Baird’s beaked whales (February–October), sperm whales (July–September), and minke whales and killer whales (April–July) feed in the waters every year during their respective seasons. Observe the whales from the lookout point at the Whale Observation Hill Park, or join a whale watching tour to view them at close range.
Seals and Steller’s sea lions
Spotted seals and ribbon seals regularly winter in Shiretoko, and Steller’s sea lions are active in the area periodically from December to April. The majority of the Steller’s sea lions are pregnant females who nourish themselves on the ample food sources in the Nemuro Strait. Observe the Steller’s sea lions on a boat tour.
Salmon
The presence of cherry salmon and dolly varden in Shiretoko rivers is a testament to the water’s purity, as both of these freshwater species require pristine aquatic conditions to live. Pink salmon and chum salmon, that live in the Pacific Ocean, head for Shiretoko’s river and streams to spawn. Visitors can observe these salmon making their journey upstream between September and November at multiple spots along the Nemuro Strait coastline.