Didn’t the whole culture starve to death after making the heads?
Their own oral tradition is, there were three major revolts against the ruling Long-ears; each time the Long-ears and families would take refuge on a neck of land they had fortified with stones, earth, and fire. The third time this happened they were betrayed (by a woman who had married in from the Short-ears) and were slaughtered but for one. Later on a couple Long-ears who had escaped to the quarry but had starved to death there became the models for a traditional common subject for wood carving:
http://en.wikipedia.org/wiki/File:Skeletal_easter_island_statue.JPG
http://www.google.com/images?q=wood+carving+easter+island
In the quarry itself there’s an unfinished statue, all but done, over 90 feet in length, which is speculated to have been the last straw. In that scenario, the Short-ears threw down their tools (which supposedly can still be found in the quarry) and rebelled.
What followed was the Birdman phase, which lasted perhaps 100-150 years, and a lot of that time the extended families spent hiding in their own caves, involved in an island-wide feud. There is of course a strictly political view that everything on the island was peachy until Europeans visited and destroyed the entire ecosystem. This outlook is exactly congruent with the Nation of Islam’s idiotic racist fantasy about the past.
Europeans first arrived in the form of Captain Cook’s expedition, I think. An earlier voyage to find this rumored island was a failure because the titular head of the expedition couldn’t get the pee-pants captain to sail in the correct direction. Had that succeeded, Europeans would have arrived when the statues were still being built! That would have settled a lot of questions I think, and perhaps have resulted in a continuity that is lacking now.
Interesting, a bearded statue:
http://en.wikipedia.org/wiki/Rano_Raraku#Tukuturi
http://en.wikipedia.org/wiki/File:Moai_Easter_Island_geod0095.jpg
the wiki-wacky pedia entry:
http://en.wikipedia.org/wiki/Easter_Island