3500 years of shellfish mariculture on the Northwest Coast of North America

Using the Fossil Record to Understand Extinction Risk and Inform Marine Conservation in a Changing World

Understanding the long-term effects of ongoing global environmental change on marine ecosystems requires a cross-disciplinary approach. Deep-time and recent fossil records can contribute by identifying traits and environmental conditions associated with elevated extinction risk during analogous events in the geologic past and by providing baseline data that can be used to assess historical change and set management and restoration targets and benchmarks. Here, we review the ecological and environmental information available in the marine fossil record and discuss how these archives can be used to inform current extinction risk assessments as well as marine conservation strategies and decision-making at global to local scales. As we consider future research directions in deep-time and conservationpaleobiology, we emphasize the need for coproduced research that unites researchers, conservation practitioners, and policymakers with the communities for whom the impacts of climate and global change are most imminent.

Reciprocal Contributions between People and Nature: A Conceptual Intervention

Throughout human history, Indigenous and local communities have stewarded nature. In the present article, we revisit the ancestral principle of reciprocity between people and nature and consider it as a conceptual intervention to the current notion of ecosystem services commonly used to inform sustainability transformation. We propose the concept of reciprocal contributions to encompass actions, interactions, and experiences between people and other components of nature that result in positive contributions and feedback loops that accrue to both, directly or indirectly, across different dimensions and levels. We identify reciprocal contributions and showcase examples that denote the importance of reciprocity for our ecological legacy and its relevance for biocultural continuity. We suggest that the concept of reciprocal contribution can support transformation pathways by resituating people as active components of nature and restructuring institutions so that ethical principles and practices from Indigenous and local communities can redirect policy approaches and interventions worldwide.

The Anthropology of Aquaculture

Aquaculture is nothing new. It has a long, fascinating history that stretches from antiquity at least 8,000 years ago. What is new is the evolution of aquaculture in modern times into highly intensive monocultures which arose in the 1970–1980's. Modern aquaculture production has grown worldwide but remains concentrated in Asia due to the: (1) increased demands for aquatic foods as explosive population growth occurred in coastal cities with increasing affluence, (2) expansion of scientific and engineering breakthroughs, (3) high export values of aquatic foods, and (4) sharp decline of costs of global to local transport/shipping. The pioneering anthropologist Claude Levi-Strauss brought the idea of “structuralism” to anthropology: the concept that societies throughout history followed universal patterns of behavior. A qualitative document analysis of the key anthropological literature to assess aquaculture developments from antiquity to the beginning of the modern era was conducted to evaluate if there was adequate evidence to support a theory of anthropological “structuralism” for aquaculture in human history. Seven case studies of the cultural/environmental history of aquaculture were reviewed in diverse parts of the world (China, Australia, Egypt, Europe, South America, Canada/USA, Hawai'i). Analysis supports the structural theory that whenever the demands of aquatic/seafood-eating peoples exceeded the abilities of their indigenous fishery ecosystems to provide for them, they developed aquaculture. Modern aquaculture concepts and new communities of practice in “restoration aquaculture” have beginnings in Indigenous anthropology and archeology in aquaculture and point the way for Indigenous nations to engage as leaders of the United Nations Food and Agriculture Organization (FAO) ecosystem approach to aquaculture worldwide. Bringing ancient knowledge of Indigenous aquaculture into the modern context is an essential part of an alternative, “radical transformation” of modern aquaculture. There is an urgent need to develop and promote locally designed and culturally appropriate aquaculture systems that fit into the livelihoods of communities as part of a larger, diverse portfolio of food security.

Habitation Sites Influence Tree Community Assemblages in the Great Bear Rainforest, British Columbia, Canada

Identifying how past human actions have influenced their environment is essential for understanding the ecological factors that structure contemporary ecosystems. Intertidal resource use by Indigenous Peoples for thousands of years has led to habitation sites containing vast shell midden deposits and facilitating long-term impacts on soil chemistry and drainage. Here we examine how these shell middens have impacted various forest metrics, such as species diversity, community composition, canopy height, and regeneration recruitment to determine if forests on habitation sites differ from the surrounding matrix. We surveyed known habitation sites with archeological evidence indicating past year-round human occupation, within the Hakai Lúxvbálís Conservancy on Calvert and Hecate Islands within the Great Bear Rainforest along British Columbia’s Central Coast. Our results demonstrate that habitation sites exhibit lower tree species richness, less relative species abundances, as such, displayed lower Shannon diversity and inverse Simpson values. The composition of tree communities on habitation sites was statistically different, with western hemlock and western redcedar densities increasing on non-habitation sites. Conversely, regeneration diversity at habitation sites was more even and exhibited elevated Shannon diversity and inverse Simpson values. The community composition of regeneration was more consistent among habitation and non-habitation sites; however, western redcedar, western hemlock and Sitka spruce were more abundant at habitation sites. For all tree species, maximum height was higher within the habitation sites; however, this trend was the most notable in western redcedar and Sitka spruce, which increased by an average of 4.8 m relative to non-habitation sites. Collectively, our findings suggest that long-term habitation alters forest community compositions. The landscape alterations within habitation sites promote conditions needed to support diverse, even, and abundant regeneration communities and consequently increase the height of the dominant coastal tree species. Thus, our results offer evidence that long-term influence by Indigenous communities have a persistent influence on coastal forests.

11,500 y of human-clam relationships provide long-term context for intertidal management in the Salish Sea, British Columbia

Climate change, habitat loss, and overharvesting are threatening coastal ecosystems worldwide. A less widely recognized threat is the decline in Indigenous mariculture practices. These practices, such as building of clam gardens, structured coastal ecosystems for millennia. Teasing out the dynamic and intertwined relationships between humans and culturally valued species, such as clams, requires long-term paleoecological and archaeological records. These records are requisite for creating meaningful management targets and for applying traditional mariculture practices, such as the tending of clam gardens, to increase the productivity and sustainability of our foods today. Documenting these interactions between humans and coastal ecosystems, such as we have done here, also counteracts the erasure of the long-term connections of Indigenous peoples to their lands and seas.

Historical ecology can provide insights into the long-term and complex relationships between humans and culturally important species and ecosystems, thereby extending baselines for modern management. We bring together paleoecological, archaeological, and modern clam records to explore the relationship between humans and butter clams (Saxidomus gigantea) throughout the Holocene in the northern Salish Sea of British Columbia, Canada. We compare butter clam size and growth patterns from different temporal, environmental, and cultural contexts spanning 11,500 y to present. Butter clam size and growth were restricted in early postglacial times but increased over the next few millennia. During the early-Late Holocene, humans took increasing advantage of robust clam populations and after 3.5 ka, began constructing clam gardens (intertidal rock-walled terraces). Environmental and cultural variables, including coarse substrate, stabilized sea surface temperature, and the presence of a clam garden wall, increased clam growth throughout the Holocene. Measurements of clams collected in active clam gardens and deposited in middens suggest that clam gardens as well as other mariculture activities enhanced clam production despite increased harvesting pressure. Since European contact, decline of traditional management practices and increases in industrial activities are associated with reduced clam size and growth similar to those of the early postglacial clams. Deeper-time baselines that more accurately represent clam population variability and allow us to assess magnitudes of change throughout time as well as the complex interactions among humans and clams are useful for modern marine resource management.