Fig. 4. Example 3 of the variation in the amount of caribou habitat (h) over 1000 yr. For the first 800 yr, the stochastic mean reverting process that allows harvesting is used to determine the supply of habitat. After 800 yr, the critical stopping threshold h* is reached, havesting stops, and the variation in the amount of habitat then follows the stochastic mean reverting process, which bans timber harvesting. Despite the harvesting ban, the amount of caribou habitat falls below the critical minimum habitat threshold because of natural landscape dynamics. The amount of habitat is then maintained equal to he, reflecting the hypothetical extinction of the caribou, an irreversible event.