Each piece of land has a specific carrying capacity. The carrying capacity for a piece of land is the number of animals that the land can sustain without damage to the habitat or the animals throughout the year. As in the illustration above, imagine the carrying capacity as a lake - the annual reproduction of wildlife (the rain) continuously replenishes the habitat. However the habitat can only hold so much wildlife. The runoff from the dam indicates the different factors that will affect the wildlife population in a habitat. These animals are known as the harvestable surplus. They are the animals that would expire due to other factors, and thus can be harvested by hunters without damaging the population. The quality and number of wildlife on any given piece of land is affected by the following factors (known as limiting factors):
Examples of this are chronic wasting disease, Hemorrhagic fever and parasites.
Drought conditions dry up watering holes, and snow and ice cover food sources. Too much rain can damage nesting sites.
Predators prey on the very young, old and sick animals for food.
This usually occurs when there are too many animals and not enough food.
Hunting removes the overpopulation of wildlife in a given area.
Loss of habitat to development increases the occurrences of wildlife being hit by vehicles.