Mountain-stream bait fishing from a River / Mountain stream
Dark Sleeper: Match a fine rig to the current and avoid repeatedly harvesting one spot. Check permits and harvest rules.
Waters: Rivers & lakes
Fish
Odontobutis obscurus ・ Odontobutidae (Freshwater Sleepers)
Months for Dark Sleeper are a broad Japan-wide guide and shift with region, temperature and conditions; prefer local reports and rules.
A strictly freshwater fish of river beds that grows to about 25 cm. The head is broad and flattened, with a large mouth and a jutting lower jaw, and dark blotches mark the brown body. Though a goby relative, its pelvic fins stay separate instead of fusing into a sucker. It is nocturnal, ambushing small fish and shrimp from cover.
Dark Sleeper: Match a fine rig to the current and avoid repeatedly harvesting one spot. Check permits and harvest rules.
Waters: Rivers & lakes
Stream bait-fishing starter kit ・ Kit total ¥13,000–35,000
Before buying tackle, confirm the river permit, season and allowed bait and hooks.
Product links may be affiliate links. Prices move, so treat the ranges as a guide.
Food use varies locally. Check harvest rules and water quality, avoid raw consumption and cook thoroughly.
Inland rules are water-specific. Check the fishery cooperative and prefecture for day or annual permits, closed seasons, minimum sizes, tackle, harvest and release rules.
Closed seasons and size limits — how to find the numbers, which differ by prefecture
This article organises general information and is not legal advice. Rules differ by municipality and by fishery cooperative, and they change. Always check the current rules for where you are going.
Seasons, sizes and eating quality are general guides. Rules change, so check the latest prefectural, fishery-cooperative and site rules before fishing. This app provides general information, not legal advice.