Henderson, Pitcairn, and Mangareva
By Tyler Hill
The Pitcairn, Henderson, and Mangarevan islands fell because they relied to much on trade with one another. Secondary conditions include deforestation on Mangareva, a need for water on Henderson, a lack of arable land and wood on Pitcairn, and political instability on all of the islands.
The three islands, Henderson, Pitcairn, and Mangareva, are sometimes referred to as just the Pitcairn Islands. They are nearly in the middle of the Pacific Ocean, between South America and Australia. Pitcairn is roughly 2 and 1/2 square miles and 300 miles Southeast of Mangareva. Mangareva is about 15 miles in diameter, and 1000 miles from the nearest "high" islands. Henderson is the largest of the three at 14 square miles, and 100 miles East of Pitcairn, and 400 miles East of Mangareva. There were signs of trade on all three islands until about 1000AD, and life ceased to exist by 1450 AD. Mangareva served as the center of trade for the three islands because it was the easiest to access. It had multiple, accessible bays where Henderson had rocky landings and Pitcairn had only one, nearly inaccessible, bay. Mangareva exported water to Henderson because there was no natural spring or water source on the island. Pitcairn imported food and wood from Mangareva because there was a lack of arable land and trees. In return they gave them obsidian and fine-grained bassalt because Mangareva lack good tool materials.
The evidence of trade between all of the islands is in the types of tools and materials that they used. Mangareva originally used wood, oyster shells, and coarse grained basalt for tools. However the oyster shells and basalt quickly wore down or broke. Pitcairn Island had an abundance of obsidian and fine-grained basalt, but a lack of wood. Stone that originated in Pitcairn was found on Mangareva and Henderson, and Mangarevan wood was found in tools on Pitcairn. Henderson Island did not have a natural water source, but they did have an abundance of land and sea birds which they traded for what they needed. Bird bone coming form species native to Henderson were found in refuse piles on all three of the islands.
Although Mangareva needed trade to survive, it ended up being it's downfall. Mangareva was originally forested, but the trade caused Mangareva to cut down most of its trees for canoes and trading materials, which resulted in deforestation. The lack of a major resource caused internal warfare on the island. The warfare only destroyed the environment and wild life more, and in order for some of the survivors to survive they had to turn to cannibalism. However their survival was short lived and any of those who were left alive soon died out.
The loss of trade with Mangareva caused the collapse of Pitcairn because there were no more food or wood imports. The island of Pitcairn is mostly an extinct volcano, resulting in steep slopes, and limited space resulting in poor agricultural and environmental conditions. Lack of agriculture made it hard for the island to get food, and the absence of trees quickly created a wood shortage. Therefore the island had to rely heavily on Mangarevan imports. When Mangareva collapsed, the island of Pitcairn quickly ran out of supplies. There was no wood to build boats, and food had to be rationed. Internal warfare quickly started over the remaining materials, and just like Mangareva, the inhabitants quickly died out.
*Henderson could not bring food to Pitcairn because they did not have trees long enough to make into canoes.
The loss of trade when Mangarevan collapsed hit Henderson Island the hardest. Henderson island has no natural springs or reservoirs, so the inhabitants needed to rely on what rainfall they received, and imports. When Mangareva collapsed, Henderson was left without water. Henderson could only support about 15-20 people at most with its living conditions, and the lack of water caused warfare amongst them. However war cannot make water appear from nowhere, and anyone on the island died.