What is Iwana イワナ [𩸶]?
Iwana represents the genus of chars in Japanese, some species are also referred to as “trouts“, which belong to the salmonid family. The term is predominantly used in Japanese cuisine for the whitespotted char. Both land-enclosed freshwater forms and marine iwana exist.
The tratidional character for iwana 𩸶 or 岩魚 is composed of the character for “rock“ 岩 (iwa, いわ) and “fish“ 魚 (sakana, さかな). This can be interpreted as a fish that lives in mountain streams or prefers a rocky environment.
Iwana as an ingredient for Sushi and Sashimi
The bright and shiny, white to reddish meat has a light and pleasing taste. The smell is very neutral and the aromas are subtle. The taste of the meat can be intensified by marinating in vinegar marinade (sujime). Iwana is therefore also suitable for preparation as „pressed sushi“ (oshi-zushi, 押し寿司).
Compared to salmon, which belongs to the same family, the taste of iwana is less full-bodied and more restrained. In particular, char that spend most of their lives in fresh water have a slightly “earthy” flavor.
The spawning season depends on the region and subspecies. It takes place in many tributaries of the main stream from September to January. Therefore, the period from May to September is considered the best season for iwana.
Iwana offered on the market often come from aquaculture and are available all year round.
Characteristics & Ecology
Iwana prefers fast flowing, oxygen-rich, cool and clear waters with gravel or sand bottom. They are fast swimming predators that feed on small organisms, water insects, other fish, insects falling from shore trees and frogs.
Some iwana groups live anadromously, that means they migrate from saltwater to freshwater for spawning, these are called amemasu (アメマス) in Japanese. The term ezoiwana (エゾイワナ) is used to describe groups of iwana living in landlocked freshwater areas. Ezoiwana prefers rivers and streams with a water temperature below 15°C.
The distribution in rivers extends over different regions of Honshu and Hokkaido. In addition, the natural habitat includes the northeastern Korean peninsula via Sakhalin, the Kuril Islands to Kamchatka in the Northwest Pacific.
Subspecies of Japanese Iwana
The characteristics of iwana vary greatly from one region to another, but it is common to classify the whitespotted char into four subspecies: Amemasu, nikkouiwana, yamatoiwana and gogi. Furthermore, a distinction can be made between the whitespotted char and the dolly varden trout.
|Group||Japanese name||Scientific name|
|Whitespotted char||Amemasu (ezo iwana)
|Salvelinus leucomaenis leucomaenis|
|Salvelinus leucomaenis pluvius|
|Yamato iwana (kirikuchi)
|Salvelinus leucomaenis japonicus|
|Salvelinus leucomaenis imbrius|
Related Species of Iwana
In Japan, related species of the same genus are only partially called iwana. For example, the brook trout, is counted among the trout (masu, torauto).
|Japanese name||Common name||Native to Japan|
|Oshorokoma (Karafuto-iwana), Miyabe-iwana
|Dolly varden trout
Salvelinus malma, Salvelinus malma mitabei