New research debunks myth of Easter Island’s population collapse

Recent research has challenged long-standing myths about Easter Island's population and environmental history.

The research overturns the longstanding belief that Easter Island suffered a significant population decline due to environmental overuse. Contrary to earlier theories suggesting that the island's ancient inhabitants depleted its resources by cutting down trees to construct massive stone statues, a new study published in Science Advances reveals that the population remained relatively stable at around 3,000 people. The study indicates that the islanders employed innovative farming techniques to sustain their population, debunking the myth of widespread ecological and demographic disaster by the time Europeans arrived in 1722, Caliber.Az reports, citing foreign media.

Revising Historical Narratives Through Technology Researchers from Binghamton University have employed advanced technology to reassess the extent of rock gardens and pre-contact agricultural practices on Easter Island (Rapa Nui).

The team, including Professor of Anthropology and Environmental Science Carl Lipo, Environmental Studies Research Development Specialist Robert J. DiNapoli, and anthropology alumnus Dylan S. Davis, now a post-doctoral fellow at Columbia University’s Climate School, have provided new insights into the island's agricultural history. Easter Island, formed from volcanic eruptions a million years ago, had soil depleted of essential nutrients like potassium, phosphorus, and nitrogen, compounded by salt from ocean spray, which hindered soil fertility, explained Lipo. 

To adapt to these constraints, the islanders initially employed slash-and-burn agriculture, which temporarily enriched the soil. As deforestation progressed, they shifted to composting plant waste and using rock mulch. Rock mulch, a labor-intensive technique, involved breaking up bedrock and mixing it into the soil to restore nutrients and protect against erosion. 

This method is comparable to practices used by the Maori in New Zealand, Indigenous peoples in the American Southwest, and in the Netherlands, Lipo noted. Despite the island’s challenging soil conditions, the gardens primarily produced sweet potatoes, with dry-land taro and yams as secondary crops.

The researchers found that while earlier European reports suggested that gardens covered 10 per cent of the land, updated estimates using shortwave infrared (SWIR) satellite imagery and machine learning revealed that only about 180 acres were covered with rock mulch. This new estimate aligns with historical accounts of a population of around 3,000 people at the time of European contact. The findings suggest that rather than a population collapse, the island’s inhabitants managed to thrive within their ecological limitations through sustainable agricultural practices. 

This perspective challenges the notion of an ecological disaster and highlights the islanders' resilience in adapting to their environment. The misunderstandings about Easter Island's population size are largely due to the impressive moai statues, which have led to the belief that a large workforce was needed to construct them. Additionally, ecologists often use Easter Island as a case study for how population growth can result in environmental collapse. Lipo argues that Easter Island shouldn't be used as a convenient example for broader narratives. “We need to view the island within its own unique context,” he said. “What it reveals is quite different from the commonly held beliefs.”