The roles and impacts of human hunter-gatherers in North Pacific marine food webs

Abstract

There is a nearly 10,000-year history of human presence in the western Gulf of Alaska, but little understanding of how human foragers integrated into and impacted ecosystems through their roles as hunter-gatherers. We present two highly resolved intertidal and nearshore food webs for the Sanak Archipelago in the eastern Aleutian Islands and use them to compare trophic roles of prehistoric humans to other species. We find that the native Aleut people played distinctive roles as super-generalist and highly-omnivorous consumers closely connected to other species. Although the human population was positioned to have strong effects, arrival and presence of Aleut people in the Sanak Archipelago does not appear associated with long-term extinctions. We simulated food web dynamics to explore to what degree introducing a species with trophic roles like those of an Aleut forager, and allowing for variable strong feeding to reflect use of hunting technology, is likely to trigger extinctions. Potential extinctions decreased when an invading omnivorous super-generalist consumer focused strong feeding on decreasing fractions of its possible resources. This study presents the first assessment of the structural roles of humans as consumers within complex ecological networks, and potential impacts of those roles and feeding behavior on associated extinctions.

Linking humans to food webs: a framework for the classification of global fisheries

“…; Dunne et al . ; Worm and Paine ), given that different fishing practices are expected to (1) have different consequences for biodiversity maintenance and ecosystem stability (Smith et al . ; Garcia et al .…”

“…To identify the ecosystem impacts across this broad array of practices, fisheries scientists have developed a powerful set of quantitative management tools, including food-web and ecosystem-based approaches (eg Ecopath/Ecosim [Pauly et al 2000]; Atlantis [Fulton et al 2011]), but these approaches tend to be highly system-specific and place little emphasis on how human behavior influences the structure and stability of fisheries food webs (see Panel 1 for definitions of terms used throughout this paper). This deficit has recently led to calls for fisheries management to explicitly link human behavior to food webs (Darimont et al 2015;Dunne et al 2016;Worm and Paine 2016), given that different fishing practices are expected to (1) have different consequences for biodiversity maintenance and ecosystem stability (Smith et al 2011;Garcia et al 2012), and (2) vary with the socioeconomic status of the fishing region (Dey et al 2005). These factors represent a feedback loop that is important to consider in management decisions aimed at protecting both biodiversity and food security (Allison et al 2009).…”

Integrating Economic dynamics into Ecological Networks: The case of fishery sustainability

“…We argue that developing both sustainable management practices and a fuller understanding of anthropocene ecological dynamics require recognition that much of the ecological impact of anthropogenic activity is determined by an integrated feedback process between ecological dynamics and socio-economic conditions as a coupled natural-human system (8, 9). In short, the scope of ecological networks should contain humans as dynamic elements when necessary (10, 11). Here, we expand ecological network theory by incorporating economic dynamics into food-web models to evaluate the coupled natural-human dynamics affecting sustainability in the case of fisheries.…”

Twenty-first century approaches to ancient problems: Climate and society

“…These approaches also allow for detection of keystone species via centrality measures (93). Finally, by displaying the patterns in large datasets, they provide a source for inferences about the processes creating the food web and allow for synthesis of large amounts of information (90).…”

“…Model-based archaeology provides an arena for integrating new data and for generating understandings on how humans may both cause-and respond to-climate change both in the past and the future. Niche modelling show that changing climates lead to a major transition in subistence regimes on the Tibetan Plateau (72) Niche modelling shows that major episodes of construction and social codification each ended with reduction in the maize farming niche (80) Trophic Network analysis shows that climate change coupled with human deforestation leads to niche instability (88) Network analysis demonstrates that marine food webs were resilient to human predation despite variation in climate (90) Agent-based modelling demonstrates that group interconnedctedness rather than wealth is important in surviving climatic downturns in Mongolia ).…”