How First Nations Have Enhanced the Forest Over 13,000 Years of Habitation

While most human occupation harms the landscape, research shows that British Columbia's coastal First Nations have made the forest thrive.

There seems to be few places in the world where the persistent march of human development hasn’t resulted in habitat destruction to some extent. We come, we see, we conquer. Trees and ecosystems? Pshaw. According to the United Nations Environment Programme (UNEP), we are losing about 77 square miles (200 square kilometres) of forest each day thanks to decisions that the land should be used for something else.

But in the coastal areas of British Columbia where First Nations have lived for millennia, this is decidedly not the case. And in fact, 13,000 years of repeated occupation has had the opposite effect; temperate rainforest productivity has been enhanced, not hampered, according to research.

"It's incredible that in a time when so much research is showing us the negative legacies people leave behind, here is the opposite story," says study leader Andrew Trant, a professor in the Faculty of Environment at the University of Waterloo. "These forests are thriving from the relationship with coastal First Nations. For more than 13,000 years --500 generations -- people have been transforming this landscape. So this area that at first glance seems pristine and wild is actually highly modified and enhanced as a result of human behaviour."

© Will McInnes/Hakai Institute

The researchers looked at 15 former habitation sites in the Hakai Lúxvbálís Conservancy on Calvert and Hecate Islands employing ecological and archaeological methods to compare forest productivity. They found that trees growing at former habitation sites are taller, wider and healthier than those in the surrounding forest. They conclude that this is the result of, in large part, discarded shells and fire.

As it turns out, thousands of years of intertidal shellfish in the diet has resulted in the accumulation of deep shell middens, in some places more than 15 feet deep and covering massive expanses of forest area. The shells were there for terracing and drainage, or discarded as refuse. Depositing the shells inland has drenched the soil with marine-derived nutrients as the shells slowly break down over time; that and the careful use of fire have helped the forest through increased soil pH and vital nutrients, and also improved soil drainage.

The authors conclude: "Ecosystems with a history of extensive human use through commercial logging, development or other forms of contemporary resource extraction are often considered degraded and disturbed. Here we offer alternative consequences of extensive and long-term human management in coastal areas."

"It is clear that coastal First Nations people have developed practices that enhanced nutrient-limited ecosystems," they add, "making the environment that supported them even more productive."

It's so simple; treat the environment with respect and empathy, give it things that feed it rather than poison it, and it will be generous in return. We have a lot to learn.