Maintained nature will provide a variety of foods that can be enjoyed and utilized according to needs. The large number of fish caught indicates how well nature is maintained in the river.
Fish will not be able to live if the environment in which they live is polluted by waste that makes nature unnatural because aquatic animals are usually very sensitive to the condition of the surrounding environment.
A healthy river will produce an abundance of fish because the fish will be able to grow and reproduce well here and the food is abundant in the form of small shrimps playing among the river rocks.