Natural disasters can be considered limiting factors.

A lion and a cheetah attempt to occupy the same niche. The more aggressive lion survives; the cheetah does not.

Coyotes cross the winter pack ice and enter Newfoundland. The moose population starts to decline.

A severe frost wipes out 50% of the coffee crop in Brazil.

Due to severe overcrowding in an Asian village, many children do not survive to reach adulthood.

Since lynx prey on hares, an increase in the hare population causes an increase in the lynx population.

A severe flood in the Red River Valley causes a decline in the deer population.

Due to stress, large numbers of female lemmings miscarry their young and fail to reproduce.

Travelers who visit a crowded African village become infected with a disease caused by parasites.

Many fish die due to a change in the winds and the appearance of the El Nino ocean current off the coast of Peru and Chile.

Fish on a coral reef stake out their territory and chase away any younger fish that try to live there.

An extensive drought in the Serengeti Plain threatens wildebeest, giraffe, zebra, and springbok populations.