>>33456022I'm using fish as a blanket for water-dwelling, I'm including squids, jellyfish, seals and what-have-you in there.
The problem with Unova isn't really that they didn't add many "fishes" to the common pool, there were already too many of those, but that BW relied exclusively on new pokémon to populate its region. That meant we had only four lines populating its rivers and seas (one of them, basculin, being rushed in at the end because they realized their mistake too late). Scarcity was even worse off than Kanto.
There's probably a causal relationship between this scarcity and the fishing rod being obtainable only in the post-game, where the Unova-only rule is discarded.
Whether 'the rod is obtained late because there are few fishes' or 'few fishes being designed because the rod was obtained late' I can't really guess.
Really I would have preferred Unova's take on horsea or psyduck over that pseudo-starter monkey trio. No wonder one of them was the least popular pokémon veer in that poll.
