In Lake Nojiri, the Japanese smelt, Hypomesus nipponensis McAllister, 1963, population has been thought to be maintained by artificial spawning, and stocking efforts as natural spawning in in-flowing streams is unlikely due to the lack of inflowing stream habitat. In this study, novel resident Japanese smelt spawning was observed along the lakeshore in shallow areas with clean gravel and flow. Spawning occurred at night during early March to mid-April and eggs, confirmed on gravel substrate, progressed to the eyed state in 5–6 weeks. Although natural spawning was observed, the ratio of eggs that progressed to the eyed stage was minimal, possibly due to thick algae cover in areas with low flow velocity. Therefore, resident Japanese smelt spawning along the lake shoreline is physically possible and potentially contributes to the overall population in Lake Nojiri, but in-lake spawning alone presumably is not a biologically viable method for population sustainability due to low survival rates and egg density at present. Environmental improvements such as construction of fish ladders to suitable in-flowing spawning habitat, introduction of clean gravel to shorelines, and water level management adjusted to the smelt spawning run would contribute to higher recruitment by natural smelt reproduction, and consequently enhance the smelt production in Lake Nojiri.

在日本野味Hypomesus nipponensis的野ji湖中麦卡利斯特（McAllister），1963年，据认为是通过人工产卵来维持种群，由于缺乏流入河流的栖息地，由于流入河流中的自然产卵而进行的放养努力是不可能的。在这项研究中，在湖岸浅层砾石和水流很干净的地方观察到了日本居民的新产卵现象。产卵发生在3月初至4月中旬的晚上，卵在砾石基质上被确认，在5-6周内发展到眼睛状态。尽管观察到自然产卵，但进展到有眼阶段的卵的比例很小，这可能是由于在流速低的区域藻类覆盖较厚。因此，从物理上讲，日本居民在湖岸沿岸产生的冶炼物是可能的，并且可能对野ji湖的总人口有所贡献，但由于目前存活率低和卵密度低，单靠湖面产卵可能就不是生物上可持续的种群可持续方法。改善环境条件，例如建造鱼梯以适应合适的流入产卵栖息地，在海岸线上引入干净的砾石，以及根据熔炼产卵运行调整水位管理，将有助于通过天然熔炼繁殖提高采食量，从而提高熔炼产量。野ji湖。