World Natural Heritage Site, Shiretoko

(Written by Masaaki Tanaka)

1. Why was Shiretoko designated a World Natural Heritage site?
2. A treasure trove of living things
3. Must-sees in Shiretoko
4. Tasty sea food in Shiretoko
5.Enjoy & Consider

Why was Shiretoko designated a World Natural Heritage site?

　First of all, to briefly summarize the amazing things about Shiretoko, we can say that they are a rich environment where sea and land creatures live, a precious habitat for endangered species, and an activity that allows you to experience nature firsthand.

　Let’s see in more detail as below.

　World Heritage sites must have outstanding universal value, and with regard to natural heritage, one or more of the four registration criteria must be recognized in terms of landforms, landscapes, or ecosystems that illustrate the formation of the earth and the evolution of plants and animals.

　Specifically, they are: (1) sites of natural beauty, scenic beauty, and unique natural phenomena; (2) sites of major stages in the Earth’s history; (3) sites of the evolution and development of plants and animals, and unique ecosystems; and (4) sites of biodiversity, which are also habitats for endangered species.

　Shiretoko was registered as a World Natural Heritage site after being recognized as meeting registration criteria (3) and (4).

　Shiretoko is a narrow peninsula about 70 km long and 25 km wide at its base, located at the northeastern tip of Hokkaido, facing the southern end of the Sea of Okhotsk. The name comes from the Ainu language. In Ainu, it may mean “Sir-etok,” or “end of the earth”. It can also mean a “cape”.

　Shiretoko is the southernmost point in the northern hemisphere where drift ice comes in contact with the shore, and the rich connection between the sea and land ecosystems affected by this drift ice was highly valued, leading to its registration as a World Natural Heritage site in 2005.

　Here, changes in sea ice and a dynamic food chain have created an ecosystem from sea to land that is unparalleled in other regions.

　Convection currents develop in these nearshore waters as the surface of the seawater cools after autumn. In winter, nutrient salts accumulated near the seafloor are pushed up to the sea surface by the convection currents, which are stimulated by the fall of cold, concentrated salt water generated under sea ice.

　Therefore, in early spring, when the sea water ice begins to melt, ice algae and other phytoplankton proliferate greatly, and zooplankton such as krill that feed on them proliferate.

　In addition, small fish and shellfish that feed on them reproduce. As a result, they attract large migratory fish such as salmon, marine mammals such as seals, and birds such as Steller’s sea eagles and white-tailed sea eagles which prey on them.

　And salmon and other fish that migrate upstream to spawn provide food for the foxes, brown bears, and Blakiston’s fish owls that inhabit the forests.

　Thus, the food chain originating from the phytoplankton blooms caused by the nutrient cycle brought about by seasonal sea ice has created a continuous ecosystem of ocean, forest, and river, where the marine and terrestrial ecosystems interrelate with each other.

　You can already see that Shiretoko is a treasure trove of living things thanks to the drift ice.

　By the way, in winter, drift ice flows 1,000 km from the Amur River in faraway Siberia and fills the Sea of Okhotsk.

　Why does drift ice flow to Shiretoko?

　This is because large amounts of fresh water flow from the Amur River into northeastern Sakhalin, where drift ice is born, and the Sea of Okhotsk is a closed sea surrounded by a continent and peninsulas, and is intensely cooled by cold air masses from Siberia.

　However, drift ice used to appear in the Sea of Okhotsk in late January every year, but in recent years it has often been delayed to February. The drift ice is gradually becoming thinner and fragile enough to be swept away when the wind blows. The effects of global warming are being felt here as well. We worry that someday the drift ice will disappear from Shiretoko.

　Another point is that the Shiretoko Peninsula, with the Shiretoko Mountain Range rising in the center, shows significant differences in temperature and rainfall between the east and west. This diverse natural environment is important for the preservation of biodiversity.

　It is believed that people began to live on the Shiretoko Peninsula around 10,000 years ago. Some 1,200 years ago, maritime hunters migrated southward along the coast of the Sea of Okhotsk from the continental area and arrived in Shiretoko, this was followed by the assimilation of other peoples who had been living throughout Hokkaido for 800 years.

　It seems the Ainu people were formed among them.

　Today, the Ainu people are recognized as an indigenous people of Japan, although further efforts are needed to respect their dignity.

　The Ainu people developed a hunter-gatherer culture that lived in harmony with nature under their unique belief in the worship of Blakiston’s fish owls, killer whales, and brown bears as deities, and this culture preserved the region’s untouched nature until 130 years ago.

　Later, settlement by ethnic Japanese progressed throughout Hokkaido, but the Shiretoko Peninsula remained largely unaffected due to its harsh natural environment.

　The Shiretoko Peninsula has a high mountain range in the center of the peninsula, and the geology of the inner area is hard lava, making it completely unsuitable for cultivation.

　Several attempts were made to settle the inland area, but all failed, and the pioneers finally withdrew. As a result, Shiretoko was registered as a World Natural Heritage site, maintaining its rich ecosystem and biodiversity.

A treasure trove of living things

　The Tsugaru Straits, which separate Hokkaido and Honshu, the main island of Japan, divide not only the land but also the animals that inhabit it.

　This difference in animal ecology was discovered by Thomas Wright Blakiston, a British zoologist who stayed in Japan 150 years ago. It is called the Blakiston Line.

　For example, brown bears are found only in Hokkaido, whereas black bears are only found in Honshu.

　The area is home to 36 species of land mammals and 22 species of marine mammals. These include internationally rare species such as the Steller’s sea lion and sperm whale.

　A total of 285 bird species have been recorded, including the endangered Blakiston’s fish owl, white-tailed sea eagle, and black woodpecker. The surrounding area is a globally important wintering ground for Steller’s sea eagles, with more than 1,000 wintering individuals.

　Let us focus here on some of these precious creatures.

Blakiston’s fish owls

　Weighing around 4 kg, the Blakiston’s fish owl is about 70 cm long and over 180 cm when its wings are spread, making it the largest owl in the world.

　In the Ainu language, it is called “the god who watches over the village”. It has been cherished as a very precious being among the Ainu people. It is said that these owls guard the village at night, and when there is a threat of natural disasters or bears are approaching, they will warn humans with their cries and drive away demons to prevent danger from approaching the village.

　Blakiston’s fish owls are believed to have numbered more than 1,000 in the prewar period in Hokkaido, but the number declined due to postwar forest development and environmental deterioration, and in the 1980s the number was estimated to be only 70.

　The Ministry of the Environment confirmed 100 pairs of Blakiston’s fish owls in Hokkaido in its 2022 survey of the population of the endangered species, breaking the previous record. Nearly half of them live in Shiretoko. The Ministry believes that the population is recovering thanks to protection activities such as the installation of nesting boxes and forest conservation.

　In addition to the adult pairs, a survey conducted by attaching foot rings to chicks confirmed a record number of more than 40 chicks this year. The Ministry expects that the population may continue to increase in the future.

　The Blakiston’s fish owl is rarely seen under normal circumstances, but there are several places where it can be observed and photographed under the right conditions. Please let Hokkaido Treasure Island Travel know if you would like more information when you submit your tour application.

Killer whales

　Killer whales appear during the spring and summer months when the drift ice melts. They can grow up to 10 meters long and weigh up to 10 tons. Their lifespan is said to be as long as 80 years.

　The Ainu word for killer whale means “deity of the sea,” because they believe that killer whales chase whales around and bring them up on the beach to provide the Ainu with whale meat.

　Killer whales, also known as orcas, are at the top of the ecosystem in the sea. They live in groups of about 10 or so per family, and the Shiretoko Sea is a place for orcas to raise their young. During the three-month period from April to June, the population density of killer whales is said to be one of the highest in the world, and orcas have been seen in unparalleled numbers in Shiretoko.

　According to the latest information from researchers, one day, there were many killer whales gathering, with two groups of orcas merging and lining up side by side in a single line. Then, they swam in a mass very close together and their bodies almost collided. Some orcas were rubbing stomachs, which is said to confirm mutual intimacy. After a few minutes, they began to line up again.

　It is becoming clear that killer whales lead a unique lifestyle in which they rarely encounter their mates at the appropriate age. The oldest female is the leader of the family, and her children never leave the group. So they look for mates from other group members. When they are side by side, they look at each other, and when they break their lines repeatedly, they are said to be changing their seats.

　Researchers believe it would be like a matchmaking party.

Brown bears

　Brown bears are the largest land mammals in Japan, weighing 250 to 500 kg, and are omnivores, eating everything from leaves to insects, fish, and sometimes mammals.

　The Ainu people have long had a good relationship with brown bears as kamui (deities).

　They believe that bears are temporary representations of deities who come to visit them, bringing meat and fur as gifts.

　Especially when they get a newborn little bear in early spring after hibernation, they rejoice in their honorable role, thinking that the deities have entrusted it to them to be raised for a certain period of time.

　After one year, the soul of the little bear that has been carefully nurtured is separated from its body and its soul is sent back to its parent in the divine world in a ceremony called Iyomante.

　The spirit of the little bear, which the humans have politely sent to its parents together with souvenirs, invites the other deities to a feast, where it talks about how graciously the humans had treated the little bear, and so the other deities feel they would like to visit the human world. So when another deity actually comes to the land of humans, he transforms into a brown bear.

　This good cycle is repeated, and when the prey is given to humans, they thank the deities, which leads to more hunting the next time.

　The meat and fur of animals are gratefully used by humans, and are fully used without any waste. It is the spiritual culture of the Ainu to show their fullest feelings toward these precious souls.

　It is believed that there are now approximately 500 brown bears living on the Shiretoko Peninsula. This habitat density is the highest in the world. This is supported by the deep forests of deciduous broad-leaved trees and mixed forests that stretch across the Shiretoko Peninsula, and by the abundant food sources, such as salmon and trout that come up the rivers in the fall, Ezo sika deer, and the carcasses of whales that wash up on the coast.

Must-sees in Shiretoko

　The Shiretoko Peninsula is bisected into Shari Town and Rausu Town. Shari Town is located on the western side of the peninsula and Rausu Town on the eastern side.

Shari Town

　The base for Shiretoko sightseeing is Utoro, a 40-minute drive from the town’s central area. The eight scenic spots there are popularly known as the “Eight Views of Shiretoko,” and I will introduce a few of them below.

Shiretoko World Heritage Conservation Center

　Though this is not one of the Eight Views of Shiretoko, this facility, adjacent to the roadside station, introduces the natural attractions and highlights of the World Natural Heritage site Shiretoko, and also shows visitors the rules and manners they should observe when visiting.

　By the way, you should also try the Ezo Deer Venison Burger available at the roadside station. The venison burger is a popular, delicious and healthy local burger. It is low in fat, high in protein, and rich in iron and minerals.

Shiretoko Five Lakes

　The five lakes are located on cliffs rising from the Sea of Okhotsk. The elevated wooden pathway offers a panoramic view of the Shiretoko mountain range and the sea. It is barrier-free and visitors can walk here at any time during the open period without any procedures required.

　While the above-ground trail allows visitors to walk around and feel closer to nature, there are certain conditions in place depending on the time of year; during the season when brown bears are active, walking is only allowed when participating in a guided tour. When brown bears are confirmed to be there, the area is closed.

Frepe-no-Taki Falls

　Melting snow and rain that has seeped into the ground flows out of the cracks in the 100-meter cliffs and pours into the Sea of Okhotsk. The waterfall is also called “Maiden’s Tears” because it looks like tears as it cascades down.

Kamuiwakka Hot Spring Falls

　Kamuiwakka is a coined word from the Ainu words “kamui” (deity) and “wakka” (water). The river, which is so highly acidic that no living creature can survive in it, has been interpreted since ancient times as the work of the deities.

　Hot springs gushing from the Shiretoko Mountain Range’s Mt. Io-zan form a waterfall, and the waterfall basin is a natural open-air bath. You can climb up the river. The rocks are slippery, so wear non-slip shoes for this challenge.

Oshinkoshin Falls

　With a drop of 30 meters, it is the largest waterfall in Shiretoko. You can get close to the middle of the waterfall and feel its power. The waterfall splits into two in the middle, and its different seasonal appearances are another attraction. It has been selected as one of the 100 best waterfalls in Japan.

　It is said that the name is derived from the Ainu word meaning “a place where Ezo spruce grows in clusters”. You can see the view from the parking lot, which is about a 5-minute walk away.

Tasty sea food in Shiretoko

　Of all the fishing grounds in Shiretoko, Rausu is particularly well-known because fishing has been practiced there since long ago. Even today, Rausu products have become a representative brand of Hokkaido. In fact, when you visit the port of Rausu, you can see why. On a clear day, Kunashiri Island can be seen, and it is only about 20 kilometers away at the closest point. The waters between Kunashiri Island and the Shiretoko Peninsula are called the Nemuro Straits, and in this narrow strait 20 to 30 km wide, warm and cold currents flow in with great force, and the fish swim hard to keep up with the currents. This is why the Rausu fish are so delicious, with firm flesh and fat.

　From sea urchin and salmon roe to oversized atka mackerel cut open and dried, there is a wide variety of delicious flavors to choose from.

Enjoy & Consider

　Why don’t you consider planning a tour to enjoy Shiretoko’s great nature and animals to the fullest?

　At the same time, it is a good opportunity to think about the conservation of the earth’s natural environment.

　Join us in considering the following issues as well.

(1) In recent years, the number of Ezo sika deer has increased dramatically within the heritage area, resulting in vegetation changes and other ecological impacts. In areas where population adjustments have been implemented, vegetation has been observed to be gradually recovering.

(2) The management system has incorporated “self-regulation by fishermen” into the management of the heritage area, and has realized a system that balances the maintenance of Shiretoko’s marine biodiversity with fishing, which is the region’s livelihood.

(3) In some rivers in Shiretoko, artificially constructed river structures such as erosion control dams have prevented salmon from migrating upstream to spawn.

(4) Promote more open, community-driven initiatives, as anyone will be free to make proposals for new tourism uses and new rule-making.

　I believe that by enjoying nature to the fullest and at the same time thinking about how to connect this nature to the future, we can feel closer to nature.

　This is what each of us must keep in mind as we protect and enjoy Shiretoko’s nature for many years to come.

　And it is said “be close to the heart of nature. And from time to time, climb a mountain or spend time in the woods to purify your soul.”