Trout Species in Japan

As for the target in Japanese fishing, you cannot miss trout species. 

In this article, I will list the major trout species found in Japan.

Japan is home to several trout species, both native and introduced. These fish are highly valued for fishing (fly, lure and traditional styles) and for commercial fishing. As Japan is located in the moderate latitude, trout are selectively living across cold, clear streams, rivers, and alpine lakes, often associated with mountainous regions from Hokkaido to Honshu and parts of Kyushu. Some species are landlocked, while others are anadromous (traveling between rivers and the sea).

1. Yamame (ヤマメ, Oncorhynchus masou masou)

Common Name: Cherry Salmon or cherry trout (landlocked form)

• Native: Yes
• Distribution: Widely distributed throughout Honshu, Shikoku, Kyushu, and southern Hokkaido, primarily in mountain streams and headwaters.
• Habitat: Cold, clear mountain streams with strong oxygenation.

Biological Characteristics; 

• Belongs to the Salmonidae family.

• Non-anadromous (landlocked) form of the cherry salmon (*Oncorhynchus masou*).
• Typical adult size: 20–35 cm, but can exceed 40 cm.
• Life span: 2–4 years.
• Par marks (dark elliptical spots) on both juveniles and adults.
• Breeds during autumn, laying eggs in gravel nests.
• Subspecies: Amago アマゴ Oncorhynchus masou ishikawae, is identified as a different target to catch

Fishing Notes:

For Japanese anglers, young and old, it is highly prized for its beauty and strength. Popular among tenkara and fly fishing enthusiasts, not only for lure anglers and traditional bait anglers..

There are stocking programs in many rivers, but wild populations still persist.

2. Sakuramasu (サクラマス, Oncorhynchus masou masou)

Common Name: Cherry Salmon (anadromous form)

• Native: Yes
• Distribution: Coastal rivers from Hokkaido to northern Honshu.
• Habitat: Spends juvenile stage in rivers, then migrates to the ocean.

Biological Characteristics:

    - Anadromous variant of the yamame.

    - Grows much larger than yamame due to marine feeding.

    - Typical size: 50–70 cm, some exceeding 80 cm.

    - Silvery body without parr marks when in the ocean.

    - Spawns in upper rivers in spring (April–May) after overwintering.

Fishing Notes

This is the species known as Sima, in Russia. It is considered one of Japan’s most sought-after game fish, partially because it is difficult to catch one. The rivers which have it are limited but and its scarcity is prizing recreational fishing. The popular way to catch it is lures, and some are targeting it with flies.

3. Iwana (イワナ, Salvelinus leucomaenis)

Common Name: White-spotted Char

• Native: Yes
• Distribution: Found in Hokkaido, Honshu, Shikoku, and parts of Kyushu.
• Habitat: Cold headwater streams, alpine lakes, and, in northern regions, brackish estuaries (anadromous form).

Biological Characteristics:

• Belongs to the genus Salvelinus (chars).
• Identifiable by white spots on a dark body and lack of parr marks.
• Anadromous and landlocked forms exist (*Salvelinus leucomaenis leucomaenis*).
• Typical river size: 25–35 cm; sea-run types can reach 50+ cm.
• Spawns in autumn in gravel beds of rivers.

Fishing Notes:

Targeting this fish often entails to go deep into the mountain stream or in remote headwaters. It is a very strong fighter in relation to size. It has very aggressive characteristics, and it can attack the bait immediately after it is touching the water surface. This species can be caught with lures, flies, and natural bait.

4. Gogi (ゴギ, Salvelinus leucomaenis imbrius)

Common Name: Western White-spotted Char

• Native: Yes (Endemic)
• Distribution: Limited to Chugoku and western Shikoku regions.
• Habitat: Small, isolated headwater streams.

Biological Characteristics:

• A subspecies of the white-spotted char.
• Smaller size compared to iwana (usually 20–30 cm).
• Adapted to confined, high-elevation streams.
• Reproduction and behavior similar to iwana.

Fishing Notes:

As it lives in the limited water systems, it is extremely rare. It is so rare that it is considered a treasure among mountain stream anglers. Conservation efforts are in place due to habitat loss.

5. Biwa Trout (ビワマス, Oncorhynchus masou rhodurus)

Common Name: Biwa Salmon

• Native: Yes (Endemic)
• Distribution: Native exclusively to Lake Biwa (Japan’s largest freshwater lake) and its tributaries.
• Habitat: Deep, cold waters of Lake Biwa and its feeder rivers.

Biological Characteristics:

• Subspecies of the cherry salmon.
• Typical size: 30–60 cm.
• Spawns in tributary streams of Lake Biwa.
• Diet: Small fish and aquatic invertebrates.

Fishing Notes:

It is a premium fish as a speciality of the Shiga Prefecture, not only for the fishing target but also for the good taste. Targeted with trolling, spinning, and traditional Japanese techniques. As the distribution is limited to Biwa Lake, the harvest is strictly controlled.

6. Rainbow Trout (ニジマス, Oncorhynchus mykiss)

Common Name: Rainbow Trout

• Native: No (Introduced)
• Distribution: Stocked widely throughout Japan, especially in fishing parks, lakes, and rivers.
• Habitat: Adapted to a variety of environments but prefers cool, oxygen-rich waters.

Biological Characteristics:

•  Originally from North America.
• Strong adaptability, capable of reproducing in the wild in some regions.
• Typical size: 25–50 cm; trophy size up to 70 cm.
• Recognizable by its iridescent lateral band and black spots.

Fishing Notes:

It is an important species to be a  backbone of Japan’s trout fishery business. With the stable supply of the stock, it has become the most common target in Area Trout fishing (管理釣り場). There are various types of these artificial fishing areas. Some waters provide an easy-to-catch style of fishery that is popular among beginners and tourists. Others are holding trophy sized fish to entertain the expert anglers.

7. Brown Trout (ブラウントラウト, Salmo trutta)

Common Name: Brown Trout

• Native: No (Introduced)
• Distribution: Established self-sustaining populations in Hokkaido and parts of northern Honshu.
• Habitat: Rivers and lakes, sometimes brackish estuaries.

Biological Characteristics:

•  Native to Europe.
• Varies greatly in appearance, often with golden-brown coloration and black/red spots.
• Can grow large in lake systems (up to 80 cm).
• Prefers slightly warmer waters than other trout species.

Fishing Notes:

As a carrier of game fish tradition, this is the species longed for by experienced Japanese anglers. It is a target of lure fishing and fly fishing.

8. Ito (イトウ, Parahucho perryi)

Common Name: Japanese Taimen, Sakhalin Taimen

• Native: Yes
• Distribution: Historically found in Hokkaido and parts of the Russian Far East (Amur basin, Sakhalin, Primorye). In Japan, now only present in limited areas of northern and eastern Hokkaido (e.g., Sarufutsu, Tokachi, Kushiro River systems).
• Habitat: Prefers lowland, slow-flowing, or lake-influenced river systems with deep pools and cooler temperatures.

Biological Characteristics:

•  The only species of *Parahucho*, closely related to the genus *Hucho* (Siberian and Danube taimen).
• Largest salmonid species in Japan.
• Maximum recorded length: >120 cm (unconfirmed reports up to 150 cm).
• Maximum recorded weight: Over 20 kg.
• Longevity: Can live for over 20 years.
• Coloration: Silvery body with faint dark spots and a reddish tint on fins.
• Spawning occurs in spring after ice melt, with juveniles growing slowly.
• Top predator, feeding on fish, amphibians, and even small mammals.

Fishing Notes:

In Japan it is hard to reach this fish and is even called as the "phantom fish" due to its rarity and elusive behavior. There is a strong conservation concern, since its populations have dramatically declined due to dam construction, habitat loss, and overfishing. To deal with the situation, some regions practice catch-and-release only, and allow only a limited number of fishermen to enter a designated area. Anglers seek them with fly, such as streamers, and lure, minnows and spoons. It requires specialized knowledge and patience to catch one.

Conservation Status:

• IUCN Status: Endangered (Globally)
• Japanese Red List: Critically Endangered
• Limited populations remain mostly in protected zones and remote rivers.
• Conservation programs are in place, including habitat restoration, hatchery projects, and fishing regulations.

9. Himemasu (ヒメマス, Oncorhynchus nerka)

Common Name: Kokanee Salmon (landlocked sockeye salmon)

• Native: No (Introduced, but naturalized in some lakes)
• Distribution: Primarily in Hokkaido (Lake Shikotsu, Lake Akan, Lake Toya, Lake Onneto, etc.), and some stocked populations in northern Honshu.
• Habitat: Deep, cold, oligotrophic (nutrient-poor) lakes with clean tributaries suitable for spawning.

Biological Characteristics:

• A landlocked form of the sockeye salmon (Oncorhynchus nerka).
• Remains in freshwater its entire life.
• Typical size: 20–35 cm, but can exceed 40 cm in fertile lakes.

• Life span: 3–5 years.
• Breeds in autumn by migrating into inflowing streams or lake shallows.
• During spawning, the body turns bright red with a greenish head (similar to sockeye).
• Juveniles feed on zooplankton, while adults may eat small fish or continue feeding on plankton.

Fishing Notes:

It is a very popular target for lake trolling, bait fishing, and casting. It is known for their schooling behavior, which allows anglers to catch multiple fish in a day, if you hit the correct depth range and spot. The taste is highly praised, considered one of the most delicate-flavored salmonids in Japan. Stocking and fisheries management are active, especially in Lake Shikotsu.

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Species	Native	Anadromous	Distribution
Yamame	Yes	No	Hokkaido, Honshu, Shikoku, Kyushu
Sakuramasu	Yes	Yes	Hokkaido, Northern Honshu
Iwana	Yes	Partial	Hokkaido, Honshu, Shikoku, Kyushu
Gogi	Yes (Endemic)	No	Western Honshu & Shikoku
Biwa Trout	Yes (Endemic)	No	Lake Biwa only
Rainbow Trout	No	No	Nationwide stocked
Brown Trout	No	Partial	Hokkaido, Northern Honshu
Ito (Taimen)	Yes	No	Hokkaido only
Himemasu	No (naturalized)	No	Hokkaido, limited Honshu

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In this small island country, we have a wide variety of trout species. The land is rich in freshwater systems and the mountainous landscape gave us a lot of chances to meet these trout. 

Though these trout waters are not easy to reach from normal touristic places, it is worth experiencing them, not only for fishing but also to see the rural side of Japan.