Examples[edit]
Examples of overpopulation caused by introduction of a foreign species abound:
In the Argentine Patagonia, for example, European species such as the trout and the deer were introduced into the local streams and forests, respectively, and quickly became a plague, competing with and sometimes driving away the local species of fish and ruminants.
In Australia, when rabbits were introduced by European immigrants, they bred out of control and ate the farm crops and food that both native and farm animals needed. Farmers hunted the rabbits, and also brought cats in to guard against rabbits and rats. These introduced cats created another problem, becoming predators of local species.
Examples of overpopulation caused by natural cyclic variations include:
the 2004 Locust Outbreak in West and North Africa.
the Australian locust plagues.
Palestine's eight month long 1915 locust plague.