is a caldera lake in

Akan National Park is a national park located on the island of Hokkaidō, Japan. Along with Daisetsuzan National Park, these are the two oldest national parks in Hokkaidō. The park was established December 4, 1934. Akan is an area of volcanic craters and forests ...

, eastern

Hokkaidō is Japan's second largest island and comprises the largest and northernmost prefecture, making up its own region. The Tsugaru Strait separates Hokkaidō from Honshu; the two islands are connected by the undersea railway Seikan Tunnel. The la ...

Japan Japan ( ja, 日本, or , and formally , ''Nihonkoku'') is an island country in East Asia. It is situated in the northwest Pacific Ocean, and is bordered on the west by the Sea of Japan, while extending from the Sea of Okhotsk in the north ...

. As with many geographic names in Hokkaidō, the name derives from the

Ainu language Ainu (, ), or more precisely Hokkaido Ainu, is a language spoken by a few elderly members of the Ainu people on the northern Japanese island of Hokkaido. It is a member of the Ainu language family, itself considered a language family isolate ...

. It is the largest caldera lake in Japan in terms of surface area, and sixth largest lake in Japan. It is also the largest lake in Japan to freeze over completely in winter. The name Lake Kutcharo is also sometimes used. Kussharo Caldera & Mashu Caldera Relief Map, SRTM-1

Kussharo Caldera & Mashu Caldera Relief Map, SRTM-1

The lake's central island, Nakajima (not to be confused with another island of the same name in

Lake Tōya is a volcanic caldera lake in Shikotsu-Toya National Park, Abuta District, Hokkaidō, Japan. It is part of "Toya Caldera and Usu Volcano Global Geopark" which joins in Global Geoparks Network. The stratovolcano of Mount Usu lies on the souther ...

), is a

stratovolcano A stratovolcano, also known as a composite volcano, is a conical volcano built up by many layers (strata) of hardened lava and tephra. Unlike shield volcanoes, stratovolcanoes are characterized by a steep profile with a summit crater and per ...

. It is also Japan's largest

recursive island A recursive island or lake is an island or a lake that lies within a lake or an island. For the purposes of defining recursion, small continental land masses such as Madagascar and New Zealand count as islands, while large continental land masses ...

Volcanic gases Volcanic gases are gases given off by active (or, at times, by dormant) volcanoes. These include gases trapped in cavities (vesicles) in volcanic rocks, dissolved or dissociated gases in magma and lava, or gases emanating from lava, from volcanic ...

render the lake water

acidic In computer science, ACID ( atomicity, consistency, isolation, durability) is a set of properties of database transactions intended to guarantee data validity despite errors, power failures, and other mishaps. In the context of databases, a sequ ...

, and it supports few fish except in areas where inflowing streams dilute the water.

Rainbow trout The rainbow trout (''Oncorhynchus mykiss'') is a species of trout native to cold-water tributaries of the Pacific Ocean in Asia and North America. The steelhead (sometimes called "steelhead trout") is an anadromous (sea-run) form of the coasta ...

, which are also resistant to fairly acidic water, have been artificially introduced. In 1951, a rare form of

cicada The cicadas () are a superfamily, the Cicadoidea, of insects in the order Hemiptera (true bugs). They are in the suborder Auchenorrhyncha, along with smaller jumping bugs such as leafhoppers and froghoppers. The superfamily is divided into two ...

('' Hyalessa maculaticollis'') was discovered, and is now protected by the government. The lake is also on the migratory path of the

whooper swan The whooper swan ( /ˈhuːpə(ɹ) swɒn/) (''Cygnus cygnus''), also known as the common swan, pronounced ''hooper swan'', is a large northern hemisphere swan. It is the Eurasian counterpart of the North American trumpeter swan, and the type specie ...

. Along the lake shore are several outdoor hot springs and a sand beach with naturally heated sand and hot ground water. Wakoto Peninsula extending into the lake has a number of active sulfurous vents. The lake is also known as Japan's

Loch Ness Loch Ness (; gd, Loch Nis ) is a large freshwater loch in the Scottish Highlands extending for approximately southwest of Inverness. It takes its name from the River Ness, which flows from the northern end. Loch Ness is best known for clai ...

, after numerous reported sightings on a

lake monster A lake monster is a lake-dwelling entity in folklore. The most famous example is the Loch Ness Monster. Depictions of lake monsters are often similar to those of sea monsters. In the ''Motif-Index of Folk-Literature'', entities classified as "lak ...

dubbed Kusshii by the press from 1973. File:Lake Kussharo from Tsubetsu pass deck 2009.jpg, Viewed from Tsubetsu Mountain pass File:Lake Kussharo02.JPG, Viewed from Mt. Mokoto Prospects Park File:Kussharoko-Nakajima.jpg, Nakajima island (

Lava dome In volcanology, a lava dome is a circular mound-shaped protrusion resulting from the slow extrusion of viscous lava from a volcano. Dome-building eruptions are common, particularly in convergent plate boundary settings. Around 6% of eruptions on ...

) File:Lake kussharo sunayu with swan.jpg, Whooper swans at Lake Kussharo

References

External links

* Geological Survey of Japan *

,
Kussharo Caldera

*

- Teshikaga Town {{DEFAULTSORT:Kussharo Calderas of Hokkaido Volcanic crater lakes Lakes of Hokkaido Pleistocene calderas VEI-6 volcanoes

See also

References

External links