In 1944, the U.S. Coast Guard introduced 29 caribou to St. Matthew Island in the remote Bering Sea, off the coast of Alaska. The idea was to provide the sailors with some recreational hunting to counteract the doldrums of this godforsaken deployment. A short time later the Coast Guard did the sailors one better and closed the station, removing the caribou's only predator from the island. An ad hoc ecological experiment ensued.

The flora of this windswept outpost consists of lichens, grasses, and dwarf willow, classic tundra and a caribou banquet. With abundant vegetation, no predators, and no escape, conditions were ripe for a boom-bust cycle. And that's just what happened. In less than two decades the caribou population exploded, from 29 to 6,000, an unsustainable number on the tiny island. Tundra became trampled and overgrazed, the once plentiful food source a thing of the past. Tundra depends on the constant movement of caribou to reduce their impact in any one place, and suddenly there was no room to move on St. Matthew. The robust condition of the herd deteriorated in step with the tundra.

A year later, in 1964, after a particularly brutal winter, the population of caribou plummeted to just 42 individuals. In 1966, the caribou of St. Matthew were gone, population zero, a boom-bust cycle of just 22 years.

Lesson: Like Easter Island, St. Matthew Island was a limited space with finite resources from which there was no escape. The results were the same. Without a healthy environment there was collapse of the dominant species.