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Unique natural heritage of Hokkaido

Japan In-depth

Marimo: Scientific name Aegagropila linnaei

Marimo is a species of freshwater green algae formed when many filamentous algae become tangled up to form a ball-shaped aggregate. Marimo is also observed in Aomori Prefecture and the Fuji Five Lakes, but it is mostly found in Lake Akan-ko in Kushiro, Hokkaido. Furthermore, the Marimo in Lake Akan-ko is known for its beautiful velvety texture and the large size of spheres formed, and it has been designated as a Special Natural Monument. Marimo is also found overseas in places such as Lake Myvatn in Iceland and Lake Oisu in Estonia.

Marimo is able to perform photosynthesis. In order for the Marimo to grow to a large size, the water must be clear enough for the sunlight to reach the bottom of the lake and Lake Akan-ko meets this condition. Marimo has excellent resistance to cold weather and also tolerates darkness, so even in Lake Akan-ko that is completely covered with ice in winter, Marimo can survive. However, due to changes in the water quality, a decreasing number of Marimo is found in the wild, so studies on its cultivation are currently underway.
(C) Hokkaido Tourism Organization
 
At Akan-ko-onsen Hot Spring by Lake Akan-ko, a solemn "Marimo Festival" is held from October 8-10 by the Ainu people who have lived in this area for centuries. The Ainu call Marimo "Torasanpe" meaning "soul of the lake". After a fireworks display, the Ainu go out in dugout canoes and fetch Marimo to present to an elder waiting by the lake. Then, a torch parade is held. The following day, a ceremony is held to send the Marimo back to the lake.

If you would like a closer view of Marimo, why not visit the "Marimo Exhibition & Observation Center" on Churui-jima Island in Lake Akan-ko. Several hundred Marimo spheres are displayed there, and the story of how they form is introduced in a diorama. The Center is open from the end of April till the end of November. It takes 20 minutes from Akan-ko-onsen Hot Spring by excursion boat.
(C) Akan Tourism Association
 

Drift ice

Ice floating on the sea is generally called drift ice. When winter comes, it appears in Okhotsk Sea near the coastline and then comes onshore.
When frozen sea water is exposed to the severely cold air at the farthest northeast coast of Okhotsk Sea, it changes into needle- or board-shaped ice near the surface. The amount of ice gradually increases and the ice crystals collide or combine with each other to keep growing. They move southward and we see them as drift ice from the shores of the Okhotsk Sea.
Normally, drift ice is seen along the coast from the middle to the end of January every year, but due to changes in climatic conditions it does not appear in some years.

If you listen carefully, you can hear "kew" or "goo" sounds, as though the ice had a life of its own. This sound is considered a symbolic sound of the North Sea, so it is included in "100 sounds to keep for posterity" selected by the Ministry of Environment.
(C) Abashiri City
 
Drift ice also provides some surprising encounters. For instance, you might encounter a Clione limacine, also known as a sea angel. They are attached to the drift ice and when the drift ice disappears they go with it. This is a family of small floating sea slugs. These creatures have a transparent body about 10mm in length, and they swim gracefully as if flapping their wings.
(C) Abashiri City
 
An ecosystem is considered to exist under the drift ice. Phytoplankton lives under the drift ice, and when spring comes and the ice melts, the number of organisms increases explosively and they become food for zooplankton, shrimp and crab. When drift ice comes onshore, it's time for the fishery industry to take a rest till the spring, in accordance with the natural way of things.

Steller's sea eagles, white-tailed sea eagles and seals also come and go with the drift ice. Seals give birth and raise their young in Okhotsk.
If you are lucky, you might see animals such as the Ezo red fox playing on the drift ice.
(C) Nemuro City Tourist Association
 
Unfortunately, due to the influence of global warming, the average temperature of the Okhotsk area has increased by 0.7c°over the past century and the amount of drift ice has decreased by 40%. Therefore, the Abashiri Subprefectural Office has declared the third Sunday of February as "Okhotsk Drift ice Day" to draw attention to environmental problems and take a fresh look at the local way of life based on drift ice. Every year, different events including the creation of snow and ice candles, concerts, panel exhibitions on global warming and lectures on drift ice are held led by the Abashiri City Eco Center. This kind of activity is spreading among neighboring cities, towns and villages.
(C) Nemuro City Tourist Association
 

Spots where drift ice comes onshore

Cape Notoro, Futatsu-iwa-kaigan Coast (Abashiri)
The cliffs of Cape Notoro overlook the Okhotsk Sea and this area provides a habitat for spotted seal. You can see them up close when drift ice comes onshore from the end of January to February.
(C) Hokkaido Tourism Organization
 
[Access]
Cape Notoro ... 20 minutes by car from JR Abashiri Station
 
Okhotsk Ryu-hyo Museum
This museum is situated at the top of Mt. Tento-zan, in a suburb of Abashiri. The museum provides a simulated drift ice experience in a room where the temperature is set at -15c°. You can see drift ice there even in the summer.
(C) Abashiri Tourism Association
 
[Access]
Abashiri Station >(10 minutes by Abashiri Bus to Mt. Tento) > There is also a bus service for touring sightseeing facilities in the city (Abashiri Bus).
 
Train "Ryuhyo Norokko" (JR Hokkaido Senmou-honsen line)
There is a tram service between Abashiri and Shiretoko-Shari that takes about an hour, from which you can observe drift ice along the shores of the Okhotsk Sea. You can also experience the severe cold. Two round-trip services a day are offered from the end of January to the beginning of March every year. ¥810 for an adult.
(C) Hokkaido Tourism Organization
 
Ice-breaker cruiser "Aurora" (Abashiri)
This cruiser plows through the drift ice at a speed of 3 knots/h. It is a tremendously powerful experience to feel the cruiser jar as the hull smashes its way through the blocks of ice. You can look out over the sea from the observation deck. From the end of January to the beginning of March. ¥3,000 for an adult. Tickets must be booked in advance.
(C) Hokkaido Tourism Organization
 
[Access]
Abashiri Station > (10 minutes by Abashiril Bus to Drifting Ice Boat Terminal) >Drifting Ice Boat Terminal
 
Ice-breaker cruiser "Garinko II" (Mombetsu)
This cruiser moves forward breaking ice with a large drill set in the bow. It is a 1-hour cruise from Mombetsu Port and tickets must be booked in advance (from the end of January to the beginning of March). ¥3,000 for an adult.
(C) Hokkaido Tourism Organization
 
[Access]
Memanbetsu Airport > (20 minutes by Airport Limousine Bus ) > Mombetsu Terminal > (15 minutes by Shuttle bus) >Okhotsk Tower
 
Okhotsk Tower, Icy Ocean Observation Tower (Mombetsu)
This is the first underwater observation tower in the world. It is situated at the end of a jetty extending out from Mombetsu Port. You can look out over the Okhotsk Sea from a height of about 40 m and you can also see scenes beneath the ice from 8 m under the sea surface.
 
Drift ice walk (Shari Town)
Walk on a drift ice field wearing a dry suit. You might even see animals in the near distance. The tour usually lasts 90 minutes and the cost is about ¥5,000 for adults. The walk starts from the hotel in Utpro (from February to the end of March).
(C) SHINRA (Shiretoko Naturalist's Association)
 

Daisetsu-zan Mountains

"Daisetsu-zan Mountains" is not just one mountain, but rather a group of mountains around 2,000 m high in an area extending 63 km north to south and 59 km east to west, to form a central highland called the roof of Hokkaido. The major peak is Mt. Asahi-dake (2,290 m). The mountains create a severe natural environment with permafrost and there is an extensive alpine belt. The Ainu called these epic mountains Kamui-mintara or the "garden where gods play".

Mountain climbing is limited to the season from the end of June to the beginning of October, and the rest of the year it is closed due to snow. The first snowcap is observed around September 15 every year, which is the earliest in Japan. Ropeways and climbing routes are provided on some mountains; however, you must be equipped for mountain climbing even in the summer to prepare for sudden changes in weather. You can enjoy skiing here in winter.
(C) DO PHOTO
 
The mountains lie within an alpine belt, so there is a wide range of alpine plants including Ezo Azalea, Rhododendron and Gentian, which are beyond comparison with other mountains. As for birds, 35% of the species observed in Hokkaido can be found in the Daisetsu-zan Mountains. Also, five species of alpine butterflies that dwell in high mountains can be observed here, such as the Yellow Apollo, Freija's Fritillary and Sakhalin Holly Blue.
(C) Nemuro City Tourist Association
 
Although development is promoted in surrounding areas, animals can live in peace in the Daisetsu-zan Mountains. There are brown bears and Ezo shika deer. One particularly rare animal is the Northern Pika that lives in rocky habitat. The Northern Pika lives in low-temperature environments, and it is believed to have come from Siberia to Hokkaido when it was still connected to Siberia in the glacial age about 30-40,000 years ago. Even after the glaciers receded, Northern Pika remained in the cool mountainous areas, so they are referred to as a living fossil.
(C) Hokkaido Tourism Organization
 
Mt. Asahi-dake (Higashikawa Town, Kamikawa)
There is an Asahi-dake ropeway service between the Asahi-dake-onsen Hot Spring at the foot of the mountain and Sugatami Pond at a point 1,600 m from the hot spring.
 
[Access]
Sapporo > (80 minutes by JR Limited Express) > Asahikawa Station > (70-105 minutes by "Ideyu" Bus) > Mt. Asahi-dake Ropeway Station
 
Sounkyo Gorge/Mt. Kuro-dake
The Sounkyo Visitor Center holds an exhibition with the theme of interaction between the nature of Daisetsuzan National Park and people. They carry out solar power generation and try to incorporate natural light in order to save energy. You can get to Mt. Kuro-dake (1,984 m) from Sounkyo Gorge using a ropeway and lift.
 
[Access]
Sapporo > (80 minutes by JR Limited Express) > Asahikawa (45 minutes by JR Limited Express) > Kamikawa > (30 minutes by Dohoku Bus to Taisetsuko) > Sounkyo
 
Mt. Tokachi-dake (2,077 m)
Mt. Tokachi-dake is an active volcano continually emitting plumes of white smoke. The route has been improved, so it is relatively easy to climb in summer. At the western foot of the mountain are several good examples of Japan's famous hot springs, including the Mt. Tokachi-dake-onsen Hot Spring.
(C) DO PHOTO
 
[Access]
Sapporo Station > (80 minutes by JR Limited Express) > Asahikawa Station > (1 hour by JR Furano line) > Kami-furano Station > (45 minutes by town bus to Tokachi-dake-onsen Hot Spring) >Tokachi-dake-onsen Hot Spring