Why Coastal Tribes Are Growing Clam Gardens That Look Like Asian Rice Fields

All along the Pacific Northwest, tribes have been forced to close productive shellfish farming areas due to pollution. But they’ve got a plan.
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Researchers survey an ancient clam garden at the Gulf Islands National Park Reserve.

Photo by Ian Reid for Parks Canada.

When the tide is out, the table is set. —Tlingit proverb

In the Haida people’s creation story, the powerful trickster Raven encounters the first humans inside a giant clamshell on the shores of Rose Spit in present-day British Columbia. Though they are apprehensive at first, Raven eventually coaxes the terrified people out to play in the world.

To some, the cold, rocky beaches where this story takes place may appear barren and uninviting. But to Coast Salish tribes, they are gardens that provide physical and cultural sustenance. And for 5,000 years, clams have been a central figure.

The Lummi Nation has been forced to close 800 acres of their most productive shellfishing due to bacterial contamination.

Coast Salish people did not only harvest shellfish from the wild, but they actively managed beaches into productive clam beds to ensure a dependable food source. Today, the Clam Garden Network, a partnership of tribal members, academics, and resource managers, is reviving this practice to support food security and preserve the region’s culture. Their efforts, however, are threatened by environmental pollution that has rendered vital shellfish beds on Native lands along the Pacific Coast unsafe for consumption.

The Lummi Nation, whose reservation consists of some 21,000 acres of tidelands and uplands on Washington’s northern coast, has been forced to close 800 acres of their most productive shellfishing due to bacterial contamination from upstream dairy farms.

Shellfish harvested on lands belonging to the Swinomish and Samish tribes have been heavily contaminated by petroleum refineries, causing the closure of a once-productive shellfish beach near Anacortes.

 

Skye Augustine, Clam Garden project coordinator for Parks Canada, teaches students about traditional clam-gardening methods during a science and culture camp at the Gulf Islands National Park Reserve. Photo by Hugo Wong for Parks Canada.

Tribes hope that by investing in traditional shellfish gardening and working with upstream farmers to limit contamination, they can restore coastal shellfish habitat and improve the health of their communities.

Clam gardens resemble the rice terraces of Asia. Rocks are piled into a series of walls that delineate sections along the shore; each level descends farther into the ocean. The receding tide reveals several flat, sandy beaches.

These offer ideal clam-growing conditions. The shallow, open beds control water temperature and reduce competition for space. Once a garden is established, it begins its own legacy. Chemical signals emitted from small bits of shell left behind from broken clams guide free-swimming juveniles to settle there.

Traditional clam gardens are a stark contrast to commercial aquaculture operations.

A recent study comparing a clam garden to an unmanaged shoreline showed a doubling of production in littleneck clams and quadrupling of production in butter clams in the garden. Many clams are available only at low tides, but with a terraced beach, “the shore is basically open for longer hours and more days,” said Marco Hatch, a professor at Western Washington University and member of the Samish Indian Nation who studies marine ecology and indigenous knowledge. This equates to improved access to food for coastal communities, especially in winter when low tides occur in the middle of the night.

Traditional clam gardens are a stark contrast to commercial aquaculture operations, which depend heavily on plastics. Commercial growers use nylon bags for mussels and PVC pipes for geoduck. For decades, shellfish growers in Willapa Bay sprayed a neurotoxic pesticide on oyster beds to control ghost shrimp populations.

The gardens don’t contribute toxins to the water and actually improve local biodiversity. Raised rock walls create habitat complexity and provide protection for crustaceans and sea cucumbers—additional food sources for marine animals and people.

For First Nations today, maintaining clam gardens close to communities lowers economic barriers to healthy traditional foods.

Royal Roads University and Parks Canada are studying how the walls capture and accumulate sediment, and potentially offer a buffer for coastal storms and sea level rise. Extended terracing could have allowed for changes in sea level without affecting a community’s food source.

For First Nations today, maintaining clam gardens close to communities lowers economic barriers to healthy traditional foods by eliminating the need to travel a safe distance from industrial pollution to harvest.

The Swinomish Indian Tribal Community has also developed indicators for indigenous health that include the array of personal and communal impacts of shellfish. It’s not just about shellfish as a low-fat protein—it’s also about traditions and strong relationships.

Every age group digs clams, and the work provides an opportunity for elders to pass on intergenerational language and ecosystem knowledge that may otherwise be lost. Interviews with Heiltsuk knowledge holders point to the value of shellfishing as a family and community activity that builds and maintains social ties while offering an opportunity for cross-community and inter-government collaboration.

Members of the Clam Garden Network share ideas, research, tools, and data to expand knowledge of clam management. Some projects include a citizen science app through which users could help locate and track clam gardens.

The project has changed engagement between First Nations, government agencies, and the scientific community.

“This speaks to a bias in science: Researchers thought about hunter-gatherers, about salmon fishing, and berry gathering but didn’t focus on First Nations management or activity in intertidal regions, and never thought about First Nations people undertaking large-scale management activities like this,” said Nathan Cardinal, a Gulf Islands National Park Reserve staff member, in an interview with Royal Roads.

Hatch said the project has changed engagement between First Nations, government agencies, and the scientific community. “The collaboration around clam gardens goes beyond the involvement of First Nations as decoration,” he said. “Parks Canada and Royal Roads University brought out hundreds of elementary students to the clam gardens to have them assist research and learn from an elder. So these projects are really engaging the community through a spectrum of opportunities.”

Eight years ago, at age 19, Skye Augustine of the Stz’uminus Nation was hired by Parks Canada to learn about clam gardens. Today she is the Clam Garden project coordinator and a doctoral student of environmental management at Simon Fraser University.

Augustine experienced the educational potential of a clam garden during her first visit, as she searched the shore and learned the words for rocks and butter clams. She has since noticed a change in the conversations about shellfish. As more people become interested in eating clams from beaches near areas with high population density, water quality has become a focus.

“Because clams are filter feeders, whatever is in our water is in the clams. Whatever is in our water ends up in us,” Augustine said. This has caused people to look upstream at farming, logging, and mining practices. In her role with Parks Canada, she hears communities’ desires to reclaim traditional practices and places, and to improve access to healthy traditional foods. To accomplish that, Augustine said, they’re going to need clean water flowing from every peak.

“To see these beaches alive again, full of clams and full of people digging, laughing, telling stories, of different ages learning together—I’m excited to see them full of life,” she said.