The whales and the destruction of the environment.

At this time of the year I usually get nostalgic.
One thing that I have seen and it fills me with sadness is when many 'big whales' appear (if nothing prevents them from 'feeding') they end up displacing all the 'fish' and 'smaller whales' either 'overwhelming' or 'eating them', because the environment allows the 'big whales' to grow and grow more (in the end the environment ends up depending only on these 'big whales'), but the environment is unbalanced and the 'big whales'  are unable to maintain that environment and thus the environment disappears. Then all the 'big whales' lose everything they have invested in the environment. It is sad that not only applies to nature.