The cold, nutrient-rich waters off the Shiretoko coast — fed by the Kuril Current from the north — support one of Hokkaido's best whale-watching opportunities. Tours operate from Rausu harbour between June and August, targeting sperm whales, minke whales, orca, and Baird's beaked whales. The sighting rates are consistently high compared to other Japanese whale-watching destinations, partly because the feeding grounds are close to shore.
Sperm whales are the star attraction — large bulls can be seen close in, and their deep dives and dramatic surface displays make for excellent viewing. Orca pods visit in June and July during salmon season. Most tours run two to three hours; morning departures typically have calmer seas and better light. The harbour-side fish market in Rausu is worth a look before or after: the variety and quality of seafood reflects the richness of these same waters.