Carrying capacity refers to the maximum population size of a biological species that can be sustained by a specific environment, given the food, habitat, water, and other resources available. It is the environments maximal load, which in population ecology corresponds to the population equilibrium, when the number of deaths in a population equals the number of births (as well as immigration and emigration) . The carrying capacity is different for each species in a habitat because of that species particular food, shelter, and social requirements. The effect of carrying capacity on population dynamics is modeled with a logistic function. Carrying capacity is applied to the maximum population an environment can support in ecology, agriculture, and fisheries. Our activities can decrease or increase carrying capacity, and we alter carrying capacity when we manipulate resources in a natural environment. If a population exceeds carrying capacity, the ecosystem may become unsuitable for the species to survive, and if the population exceeds the carrying capacity for a long period of time, resources may be completely depleted.