Little Clams Make a Big Difference: Rochefortia tumida Obscure Juvenile Bivalves Survey Results on Clam Gardens

Changing climate in recent years has lead to a decrease in resiliency for marine species, negatively impacting Indigenous food systems and Indigenous peoples' ability to practice traditional ways of life. One way to increase the resilience of marine ecosystems can be found in ancient technologies used for millennia by Indigenous people, such as clam gardens. Clam gardens are an Indigenous form of shellfish management that allow coastal communities to maintain an interaction with nature that is resilient. Clam gardens were created by First Nation people by rolling rocks down the beach at low tide creating a rock wall. This rock wall created a terrace which expands clam habitat. As part of a joint project between Parks Canada and ten Coast Salish Nations, two clam gardens are being restored in the Southern Gulf Islands, BC. The purpose of this project is to determine how clam gardens are providing a unique habitat for bivalves, specifically under five millimeters. Bivalves were separated from surface sediment core samples taken from clam garden beaches and control sites. Species composition was determined for bivalves above 1mm. Results show that 89% of bivalves assessed on clam gardens were Rochefortia tumida, a unique clam which reaches a maximum length of three millimeters. These results highlight the importance of species level identification to determine the impact of clam gardens on traditional food species.