A Story of Discovery: Revealing the Mysteries of Ancient Clam Gardens

Abstract

Stories of discovery are rarely told despite being the origin of scientific innovation. Perhaps this is because discovery typically begins with failure, is often unexpected, and is exceedingly rare. Yet this is where scientific excitement begins and burgeons. By weaving together scientific experiments, with archeological data, traditional knowledge and ethnographic records, we will share our story of surprise, camaraderie and unexpected results en route to learning about how clam gardens work. Our discovery, or in this case re-discovery, revealed that ancient clam gardens have four times the number of butter clams and twice the number of littleneck clams compared to typical unmodified clam beaches. Furthermore, baby clams transplanted in to the sediment of these ancient intertidal gardens grew almost twice as fast and were more likely to survive than those transplanted in typical calm beaches. Something about these ancient gardens was unique and an experiment we thought would never work led us to one of the answers. We discovered that by reducing the slope of a beach, clam garden terraces expand clam habitat right at the optimal intertidal height at which clams grow and survive best. Moreover, a diversity of mariculture techniques and governance practices were used to increase and maintain the production of clams. Recent research has revealed that clam gardens were embedded within a diverse portfolio of resource use and management strategies that may have conferred resilience to past coastal communities by maintaining reliable access to diverse and productive food resources. Sustaining local and global food production, while maintaining resilient ecosystems, is one of the greatest environmental and humanitarian challenges of our time. Here, we share our story of discovery into how human ingenuity from the past can provide practical insights into marine conservation strategies that can support food security and sovereignty today