Population Size Influences
Immigration is the number of individuals coming into the population. Since there are deer coming into the population, the population's size would increase.
Emigration would cause the deer population to decrease because emigration is the number of individuals leaving the population.
When deer are being born, the population size would increase. When deer die, the population size would decrease.
If there are limited resources, the population could become larger than the number of resources available to them. Since there are not enough resources due to the increase of individuals, the population growth would reach its carrying capacity. Carrying capacity is when the maximum number of individuals of a particular species that the environment can normally and consistently support is reached. The species growth would increase again slowly after that.
If the number of deer continuously increases and the food supply they need does not increase, the population would reach its carrying capacity and would slowly increase in size from that point forward due to the limited resources in its environment.
These are factors that are affected by the number of individuals in an area. Limited food would cause the population size to change because there is only so much food available to the population. The size would decrease at first since there is not enough food for every individual. Another factor is disease. Disease would cause the population size to decrease as well because the animals are dying.
They are environmental factors that affect a population regardless of the population density. Storms and droughts are examples of this because they would both cause disruptions in the population.