Overpopulation occurs when a species’ population exceeds the carrying capacity of its ecological niche. Moreover, it means that effects of overpopulation pdf there are too many people in the same habitat, people are limiting available resources to survive. In the wild, overpopulation often results in growth in the populations of predators.
In the absence of predators, species are bound by the resources they can find in their environment, but this does not necessarily control overpopulation, at least in the short term. An abundant supply of resources can produce a population boom followed by a population crash. Rodents such as lemmings and voles have such cycles of rapid population growth and subsequent decrease.
Snowshoe hares populations similarly cycled dramatically, as did those of one of their predators, the lynx. The introduction of a foreign species has often caused ecological disturbance, as when deer and trout were introduced into Argentina when rabbits were introduced to Australia, and indeed when predators such as cats were introduced in turn to attempt to control the rabbits. Some species such as locusts experience large natural cyclic variations, experienced by farmers as plagues. Human overpopulation occurs when the ecological footprint of a human population in a specific geographical location exceeds the carrying capacity of the place occupied by that group.
Overpopulation can further be viewed, in a long term perspective, as existing when a population cannot be maintained given the rapid depletion of non-renewable resources or given the degradation of the capacity of the environment to give support to the population. The term human overpopulation refers to the relationship between the entire human population and its environment: the Earth, or to smaller geographical areas such as countries. Overpopulation can result from an increase in births, a decline in mortality rates, an increase in immigration, or an unsustainable biome and depletion of resources.