Polynesian colonization and landscape changes on Mo’orea, French Polynesia: The Lake Temae pollen record

Abstract

An analysis of sediment cores from Lake Temae utilizing pollen, accelerator mass spectrometry (AMS) dating, magnetic susceptibility measurements, and charcoal particle counts was undertaken to assess landscape transformation following Polynesian colonization of Mo’orea in the Society Islands. A significant influx of terrigenous sediment accompanied by increases in charcoal and the presence of the Polynesian cultigen Colocasia (taro) are indicative of human presence on the island by at least 1060–980 cal. yr BP. Polynesian arrival resulted in the rapid alteration of lowland vegetation illustrated in the pollen record by the removal of the coastal tree Pandanus and the promotion of more economically important trees such as Cocos. The most significant period of burning in the charcoal data overlaps with archaeological evidence for expansion into the island interior and the establishment and growth of more intense agricultural practices from 700 to 500 cal. yr BP. The pollen record also documents the apparent abandonment of the coastal plain near Lake Temae during this phase of inland expansion with the terrestrial landscape returning to an environment similar to that found before colonization. A final phase of environmental transformation commenced with European contact at the end of the 18th century and is marked most clearly in the Lake Temae sequence with the conversion of the system to a freshwater body accompanied by the expansion of the freshwater reed Typha and a level of burning not seen at any time over the previous 1000 years. Importantly, the new data from Lake Temae support the colonization model for central Eastern Polynesia of ca. 1000 cal. yr BP and refute the late settlement scenario for the Society Islands.