Clam gardens point to ancient marine management
May 14, 2015 by Ancientfoods
Clam garden in the Broughton Archipelago. Image: Simon Fraser University
Casting a large interdisciplinary research net has helped Simon Fraser University archaeologist Dana Lepofsky and 10 collaborators dig deeper into their findings about ancient clam gardens in the Pacific Northwest to formulate new perspectives.
Lepofsky’s research team has discovered that Northwest Coast Indigenous people didn’t make their living just by gathering the natural ocean’s bounty. Rather, from Alaska to Washington, they were farmers who cultivated productive clam gardens to ensure abundant and sustainable clam harvests.
Dating the stone terraces
SFU archaeologist Dana Lepofsky participates in the ecological survey of clams in clam garden. Image: Simon Fraser University
In its new paper published by American Antiquity, Lepofsky’s team describes how it isolated novel ways to date the stone terraces that created clam beaches. These beaches are certainly more than 1,000 years old and likely many thousands of years older. The researchers identified many places where people built gardens on bedrock — creating ideal clam habitats where there were none before. This, the researchers concluded, clearly challenges the notion that First Nations were living in wild, untended environments.
“We think that many Indigenous peoples worldwide had some kind of sophisticated marine management, but the Pacific Northwest is likely one of the few places in the world where this can be documented,” says Lepofsky. “This is because our foreshores are more intact than elsewhere and we can work closely with Indigenous knowledge holders.”
Clam Garden Network
The researchers, who worked with First Nations linguistic data, oral traditions and memories, geomorphological surveys, archaeological techniques and ecological experiments, belong to the Clam Garden Network. It’s a coastal group interested in ancient clam management.
“Understanding ancient marine management is relevant to many current issues,” says Lepofsky.
Her team is comparing clam garden productivity to that of modern aquaculture and assessing whether the shell-rich beaches of clam gardens help buffer against increasing ocean acidification. The team will also build experimental clam gardens, applying many of the traditional cultivation techniques learned from First Nations collaborators as a means of increasing food production and food security today.
Three year study
This latest study is on the heels of one done a year ago by Lepofsky and her collaborators. The original three-year study published in PLOS ONE (Open Access) found that these ancient gardens produced quadruple the number of butter clams and twice the number of littleneck clams as unmodified clam beaches. It was the first study to provide empirical evidence of the productivity of ancient Pacific Northwest clam gardens and their capacity to increase food production.