Kingdom Animalia Order Salmoniformes Genus Oncorhynchus Higher classification Oncorhynchus | Phylum Chordata Family Salmonidae Scientific name Oncorhynchus rhodurus Rank Species | |
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Similar Oncorhynchus, Gila trout, Mexican golden trout, Apache trout, Satsukimasu salmon | ||
The Biwa trout (Oncorhynchus rhodurus) is an anadromous salmonid fish of the genus Oncorhynchus, endemic to Lake Biwa in Shiga Prefecture, Japan, but also introduced to Lake Ashi and Lake Chūzenji. While called trout, the fish is most closely related to the masu salmon Oncorhynchus masou of the western Pacific, and is most often considered a subspecies of it, Oncorhynchus masou rhodurus.
Adult Biwa trout usually range from 40 to 50 cm in length and 1.5 to 2.5 kg in weight although large specimens can be up to 70 cm long and 5.0 kg in weight.
This fish feeds on plankton, aquatic insects, freshwater prawns, worms, ayu and other small fishes and, sometimes, small mammals. It is found only in the waters of northern Lake Biwa.
Use as food
Biwa trout represents a unique food fish for the Shiga prefecture. Biwa trout and its caviar are considered a delicacy. Usual ways to prepare the trout is as sashimi, by grilling with salt, in meuniere, or by smoking, deep-frying or simmering, etc. The fish has a reputation as being very difficult to catch by angling.