In the waters around Ukui in Nachikatsuura, Wakayama Prefecture, visitors can take part in exciting whale-watching cruises and observe whales and dolphins in their natural habitat. From spring through summer, these magnificent marine animals travel through the waters of the Kumano-nada Sea, offering travelers a memorable experience unique to the Pacific coast of southern Wakayama.
Whale-watching boats generally operate from around late March through September. After boarding at Ukui Port, participants head out into the open sea on a cruise lasting approximately 3.5 to 4 hours.
Influenced by the warm Kuroshio Current, the Kumano-nada Sea is a rich marine environment supporting a remarkable variety of ocean life. This abundance makes the area one of Japan’s notable destinations for whale watching and marine wildlife encounters.
One of the greatest attractions of whale watching in this area is the possibility of encountering enormous sperm whales. These magnificent whales can reach approximately 18–20 meters in length and weigh around 50 tons.
The sperm whale is the largest of the toothed whales and is famous for its ability to dive to great depths. Watching one surface to breathe before raising its tail and disappearing into the deep blue water is an unforgettable sight.
The chances of encountering sperm whales are particularly favorable from approximately March through July. During this period, whales may be seen traveling through the waters of the Kumano-nada Sea, including individuals accompanied by young calves.
Seeing the enormous tail fluke rise high above the surface just before a whale begins a deep dive is one of the most spectacular moments of the cruise.
Sperm whales are not the only marine mammals that may appear. Depending on the season and conditions at sea, visitors may also encounter humpback whales, minke whales, right whales, orcas, and false killer whales.
The waters are also home to several species of dolphins, including bottlenose dolphins, striped dolphins, and Risso’s dolphins. Seeing a group of dolphins swimming alongside the boat or leaping energetically from the water can be just as exciting as encountering a whale.
Because these are wild animals, every cruise is different. The possibility of seeing a completely unexpected species is part of the adventure.
The attraction of a whale-watching cruise is not limited to whales and dolphins. The rich ecosystem of the Kumano-nada Sea means that visitors may also encounter a variety of large marine creatures.
Depending on the conditions, sightings can include ocean sunfish, manta rays, and sharks, as well as other marine life.
The animals encountered vary from day to day according to weather, sea conditions, season, and the movements of the animals themselves. No one can predict exactly what will appear next, creating a sense of anticipation throughout the cruise.
That element of uncertainty is part of what makes whale watching so exciting. Every sighting is a gift from the wild ocean.
Nanki Marine Leisure Service, based at Ukui Port, offers whale-watching tours operated by local fishermen.
The boats used for the tours, including the Shinsho-maru and Keiryo-maru, are working fishing boats that normally operate in the waters of the Kumano-nada Sea. Their experienced captains have an intimate knowledge of the local ocean and its marine environment.
The operators also make use of information shared through their network of local fishing boats, helping them locate areas where whales and dolphins may be present.
Of course, whale watching takes place in nature, so there is no guarantee that whales or dolphins will be seen. This uncertainty is an essential part of the experience. When a whale finally appears on the horizon or surfaces beside the boat, the excitement is all the greater precisely because the encounter cannot be guaranteed.
For travelers staying around Katsuura Onsen, early-morning transportation to the departure area may also be available depending on the tour arrangements, making it easier to combine whale watching with a stay in the hot spring resort area.
Whale watching in Ukui is more than simply a sightseeing activity. It offers an opportunity to experience the richness of the Kumano-nada marine ecosystem and develop a deeper appreciation for the wildlife that inhabits the open ocean.
Standing on a boat surrounded by the vast Pacific and suddenly seeing a gigantic whale surface nearby is an experience that can stay with travelers for a lifetime. Watching playful dolphins leap through the waves can be equally memorable, especially for families traveling with children.
The experience also provides a chance to appreciate the relationship between the local community and the sea. The fishermen who operate these tours have spent years working in the waters around Kumano, and their knowledge helps visitors understand the character of this remarkable marine environment.
The departure area at Ukui Port is approximately a 5-minute walk from JR Ukui Station on the Kisei Main Line, also known as the Kinokuni Line.
This convenient access makes it easy to include a whale-watching cruise in a sightseeing itinerary around Nachikatsuura or combine it with a stay at the nearby Katsuura Onsen resort area.
From spring through summer, the waters of the Kumano-nada Sea become a stage for unforgettable encounters with whales, dolphins, and other remarkable marine creatures.
For travelers looking for an adventure that combines the vastness of the Pacific Ocean with the excitement of encountering wildlife in its natural environment, whale watching from Ukui is an experience not to be missed.