Biwa trout
Encyclopedia
The Biwa trout or Biwa salmon, Oncorhynchus masou rhodurus, is an anadromous salmonid fish of the Pacific salmon genus Oncorhynchus. It is one of several fish called trout
, but taxonomically it is a subspecies
of the more widespread cherry salmon of western Pacific
. It is enzootic
to Lake Biwa
in Shiga Prefecture
, Japan
, and is found only in the waters of northern Lake Biwa.
The Biwa trout feeds on plankton
, aquatic insects
, freshwater prawn
s, worms, ayu
and other small fishes and, sometimes, small mammals. Biwa trout represents a unique food fish for the Shiga prefecture. The fish has a reputation as being very difficult to catch by angling
.
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.
Trout
Trout is the name for a number of species of freshwater and saltwater fish belonging to the Salmoninae subfamily of the family Salmonidae. Salmon belong to the same family as trout. Most salmon species spend almost all their lives in salt water...
, but taxonomically it is a subspecies
Subspecies
Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...
of the more widespread cherry salmon of western Pacific
Pacific Ocean
The Pacific Ocean is the largest of the Earth's oceanic divisions. It extends from the Arctic in the north to the Southern Ocean in the south, bounded by Asia and Australia in the west, and the Americas in the east.At 165.2 million square kilometres in area, this largest division of the World...
. It is enzootic
Enzootic
Enzootic is the non-human equivalent of endemic and means, in a broad sense, "belonging to" or "native to", "characteristic of", or "prevalent in" a particular geography, race, field, area, or environment; native to an area or scope....
to Lake Biwa
Lake Biwa
is the largest freshwater lake in Japan, located in Shiga Prefecture , northeast of the former capital city of Kyoto. Because of its proximity to the ancient capital, references to Lake Biwa appear frequently in Japanese literature, particularly in poetry and in historical accounts of battles.-...
in Shiga Prefecture
Shiga Prefecture
is a prefecture of Japan, which forms part of the Kansai region on Honshu Island. The capital is the city of Ōtsu.- History :Shiga was known as Ōmi Province or Gōshū before the prefectural system was established...
, Japan
Japan
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...
, and is found only in the waters of northern Lake Biwa.
The Biwa trout feeds on plankton
Plankton
Plankton are any drifting organisms that inhabit the pelagic zone of oceans, seas, or bodies of fresh water. That is, plankton are defined by their ecological niche rather than phylogenetic or taxonomic classification...
, aquatic insects
Aquatic insects
Aquatic insects live some portion of their life cycle in the water. They feed in the same ways as other insects. Some diving insects, such as predatory diving beetles, can hunt for food underwater where land-living insects cannot compete.-Breathing:...
, freshwater prawn
Prawn
Prawns are decapod crustaceans of the sub-order Dendrobranchiata. There are 540 extant species, in seven families, and a fossil record extending back to the Devonian...
s, worms, ayu
Ayu
The or sweetfish, Plecoglossus altivelis, is an amphidromous fish, the only species in the genus Plecoglossus and in family Plecoglossidae. It is a relative of the smelts and is placed in the order Osmeriformes...
and other small fishes and, sometimes, small mammals. Biwa trout represents a unique food fish for the Shiga prefecture. The fish has a reputation as being very difficult to catch by angling
Angling
Angling is a method of fishing by means of an "angle" . The hook is usually attached to a fishing line and the line is often attached to a fishing rod. Fishing rods are usually fitted with a fishing reel that functions as a mechanism for storing, retrieving and paying out the line. The hook itself...
.
Appearance
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.Use as food
Biwa trout and its caviarCaviar
Caviar, sometimes called black caviar, is a luxury delicacy, consisting of processed, salted, non-fertilized sturgeon roe. The roe can be "fresh" or pasteurized, the latter having much less culinary and economic value....
are considered a delicacy. Usual ways to prepare the trout is as sashimi
Sashimi
Sashimi is a Japanese delicacy. It consists of very fresh raw meat, most commonly fish, sliced into thin pieces.-Origin:The word sashimi means "pierced body", i.e...
, by grilling
Grilling
Grilling is a form of cooking that involves dry heat applied to the surface of food, commonly from above or below.Grilling usually involves a significant amount of direct, radiant heat, and tends to be used for cooking meat quickly and meat that has already been cut into slices...
with salt, in meuniere, or by smoking, deep-frying or simmering
Simmering
Simmering is a food preparation technique in which foods are cooked in hot liquids kept at or just below the boiling point of water , but higher than poaching temperature...
, etc.