Paleo-archives of past cultures, seabirds, and their changing connectivity to ecosystems

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Natural, long-term environmental fluctuations and anthropogenic impacts to coastal regions can markedly alter wildlife populations, and in turn affect the people that rely on them. Over the past ~8000 years, Newfoundland and Labrador had at least three pre-European settlement episodes by distinct cultural groups: Maritime Archaic, Paleoeskimo, and Indigenous (Beothuk). However, discontinuities across archaeological records allude to climatic changes that likely resulted in lifestyle shifts leading to settlement abandonment or the complete extirpation of cultural groups. Past climatic changes would have influenced the availability of marine and terrestrial food resources, which in turn contributed to the success and permanency of settlements. For example, seabirds were an important component of Paleoeskimo and Beothuk culture and diet. However, modern data suggests that seabird populations decline with large changes in sea surface temperatures, and thus, seabirds would have been less likely to support past culture diet during warm periods over the Holocene. Over the next five years, my objectives are to reconstruct lake and peatland ecosystem responses to human settlements across Newfoundland and Labrador over millennia, investigating how changes in climate and European arrival influenced land use by past cultures (Theme 1), and to understand how climate variability and human pressures are linked to the long-term population dynamics of nesting seabirds (Theme 2). My research will use paleo-archives to reconstruct histories of environmental relationships between past cultures, dense animal populations (e.g., caribou, seabirds), and land use, in the context of climatic forcing. Theme 1 will examine biological and geochemical proxies in paleo-archives collected adjacent to Paleoeskimo and Indigenous basecamps to understand timing of occupation, impacts, and resulting environmental changes. Working in close collaboration with some of Canada's leading ornithologists, Theme 2 uses both modern and paleoecological studies from sub-Arctic ecosystems neighbouring seabird colonies to study past population fluctuations, placing these changes within broader environmental and climatic contexts. Notably, my research has developed fecal lipid biomarkers to track past human and seabird activity in lake catchments and peatlands, as well as to pinpoint whether animal feces were a source of organic nutrients to lakes, contributing to cultural eutrophication of aquatic ecosystems. Combining these fecal lipid biomarkers with biological subfossils that track climatic change, our dated paleo-archives will provide robust reconstructions of past environmental conditions at sites of cultural and ecological importance to early peoples in Newfoundland and Labrador and Canadians. This research has significant implications on our understanding of factors driving past ecological changes, as well as ecosystem and cultural resilience to environmental and climatic stressors.