It declines. Members above will die off due to starvation, and members immediately below will proliferate and kill off (through predation) the members below themselves.
The optimal density of a population is the number of individuals that can support an ecosystem without imbalances. When the number of individuals of some trophic level increases due to an increase in birth rates or migrations, there is a decrease in the amount of food (individuals of other trophic levels), This means that higher population density, the higher the mortality caused by predators
Also as a population grows, competition increases among the individuals that make it up because resources are limited.
