People emigrated from South America on boats made from reeds. They wrecked the ecology of the island and ended up starving themselves to death. It's as simple and far-reaching as that.

Well, I'm doing a project on this. My theory is that they came to Easter Island. Then, they built the statues as gods. It worked them so hard everyday that they had to eat alot everyday. So they ate alot everyday, and ran out of food. Then, they resorted to cannibalism. They all died or were eaten..just saying. OR They were starving after all of their work, and then..even though they were tired, they built ships. And left. But then, their ships sank..or got caught in big storms. The End

Easter Island is a trade route along a chain of volcanic islands which stretched from the west coast of South America throughout the Polynesian islands. San Felix, Pitcairn, Mangareva and many other islands are part of this chain. The size of Easter Island promoted settlement by Polynesians and over the years government by an elite small group. Population growth became a problem with limited land to cultivate and poor fishing, so the government instituted a number of public jobs programs supported by taxes to keep the populace busy. The government soon recognized the benefits of building stone structures and promoting sports activities. Sports like ocean swims, cliff diving and collecting the first bird egg of the season from the cliffs caused many deaths, thus reducing the overpopulation. Early stone carvers were commissioned to create large stone heads to commemorated the winner of the many sports competitions. Soon the carving of such heads became a sport in itself where teams of carvers raced to cut and move the largest stone head to commemorate another winner. The process of carving and transporting and erecting the heads killed many stone carvers and again reduced the overpopulation. The many sports and industrial accidents had only a small impact on overpopulation because the surviving male population kept the much larger female population pregnant. The ladies had no interest in sports or carving stone to reduce their population.

I think that some bunnies did. Just my theory.