True, but by comparison where the separate life stages of eels were believed to be entirely different species up until the 1800', salmon were relatively well known both in North America and Japan.
It was understood what Fry and smolts were. The different species and their specific breeding cycles, including which rivers would contain which species in a given season were known and there was generally a large 'industry' and culture built around them on both sides of the Pacific.
Likewise, from what that article says, eels were a heavy part of many cultures, yet the beliefs around them were fairly ignorant, for lack of a better word, by comparison.
It was understood what Fry and smolts were. The different species and their specific breeding cycles, including which rivers would contain which species in a given season were known and there was generally a large 'industry' and culture built around them on both sides of the Pacific.
Likewise, from what that article says, eels were a heavy part of many cultures, yet the beliefs around them were fairly ignorant, for lack of a better word, by comparison.