SUSTAINABLE SEAFOOD: What can ancient oyster fisheries teach us about sustainable harvesting today?

Globally, oyster populations have been declining. Oyster management strategies often rely on knowledge and data from the past two centuries — a period during which many oyster fisheries collapsed due to overharvest, habitat loss, and other causes.

In contrast, archeological records indicate that Indigenous fisheries thrived for millennia. Understanding the historical practices of Indigenous oyster fisheries is crucial for sustainable management of modern oyster populations. Additionally, incorporating Indigenous knowledge not only promotes ecosystem health but helps to restore the rights of Indigenous communities.

Studying Indigenous Fishery Sites

Researchers collected archaeological data from their own work and a number of other sources, spanning 7,000 years of oyster data. They studied over 200 Indigenous oyster fishery sites in North America and Australia, including about 50 sites along the southern Atlantic coast from South Carolina to Florida. The team analyzed shell mounds and other archaeological debris to gain insights into the scale, longevity, and management of these fisheries.

The team also examined published and unpublished literature to learn more about the historical importance and practices around oysters in Indigenous communities.

The Results

Indigenous peoples sustained massive oyster fisheries for 5,000 to 10,000 years — or more. In the southern Atlantic region, oyster sites were especially numerous between 2500 and 1500 BCE.

Unlike modern-day commercial harvests, Indigenous management often maintained abundance, which was later exploited by settler colonial enterprises. However, some Indigenous fisheries shared commonalities with today’s commercial fisheries, like selling surplus oysters and accumulating wealth. The displacement of Indigenous societies often preceded the collapse of fisheries, with far-reaching impacts on ecosystems and the resilience of oyster populations.

Indigenous harvesting practices ranged from small seasonal camps to large villages, with some sites yielding tens of millions or even billions of oysters. The largest site in the study was in the peninsular Gulf Coast (Mound Key, Florida) with over 18 billion shells. The largest East Coast site was in South Carolina (Fig Island), with over 75 million shells.

These findings highlight the significant, controlled role Indigenous communities played in oyster harvesting — which other studies have underestimated, characterizing Indigenous fisheries as “lightly fished” or “wild.”

The Importance of Shells

Large mounds and other structures made mostly from shells show that oysters and other shellfish were important in the social, political, and religious activities of Indigenous peoples. For instance, massive shell mounds found in various regions served as platforms for rituals and ceremonies.

Despite colonization and displacement, Indigenous communities have preserved their traditional ecological knowledge related to oyster harvest and management, for example in practices like oyster farming and artificial reef construction.

Why It Matters

The state of oyster fisheries today reflects more than just environmental changes — it’s about the loss of complex socio ecological systems. While oysters are well-studied globally, archaeological data on Indigenous fisheries have been overlooked. Research suggests Indigenous oyster fisheries were sustainable because they were part of larger interconnected systems, not separate economic activities.

Working with Indigenous groups to restore their relationships with oysters and their traditional lands offers a path to healthier fisheries and environments. This collaboration could involve sharing knowledge, conducting research together, or restoring control over land management to Indigenous communities.

Finally, the authors — several whom are members of Indigenous communities from the studied territories — note the data for their study come from the colonized lands of dozens of Indigenous nations and that archaeological research and heritage management should involve consultation and collaboration with Indigenous communities.

Reading

Reeder-Myers, L., Braje, T. J., Hofman, C. A., Elliott Smith, E. A., Garland, C. J., Grone, M., …
& Rick, T. C. (2022). Indigenous oyster fisheries persisted for millennia and should inform
future management. Nature Communications, 13, 1-13. https://www.nature.com/articles/s41467-
022-29818-z

Open Access funding enabled and organized by Projekt DEAL.

<Maya Afilalo bio>

This story originally appeared in North Carolina Sea Grant’s award-winning Hook, Line & Science series.

The text from Hook, Line & Science is available to reprint and republish at no cost, but only in its entirety and with this attribution: Hook, Line & Science, courtesy of Scott Baker and Sara Mirabilio, North Carolina Sea Grant.