In this situation, there are two possibilities: also numerous fish or not adequate food. Either inadequate bass were harvested, or otherwise sufficient forage fish were stocked with the bass or there are not enough forage fish to duplicate appropriately to supply food for the bass to eat. If even more bass are taken, as well as the population is thinned, and much more forage fish are included, then there will be enough food for the remaining fish.
In the post-war WW II era, there were the first attempts at bass administration in fisheries. Farmers began to construct farm pools containing bass. At the same time, as a result of industrialization as well as contamination, many of the rivers that had had trout started to be toxified. The trout began to be exterminated. Smallmouth bass started to be introduced to replace them. After that the tiny mouth populations began to decline because of contamination as well.