Data for: Unprecedented shift in Canadian High Arctic polar bear food web unsettles four millennia of stability ...

• Main Authors: Routledge, Jennifer, Sonne, Christian, Letcher, Robert, Dietz, Runne, Szpak, Paul
• Format: Dataset
• Language: English
• Published: Dryad 2022
• Subjects: FOS History and archaeology; Polar Bear; Stable isotope data; Lancaster Sound; Arctic; Arctic Bay; Canadian Arctic Archipelago; Grise Fiord; Arctic Archipelago; Arctic bay; Phytoplankton; Qausuittuq; Sea ice
• Online Access: https://dx.doi.org/10.5061/dryad.g1jwstqv4; https://datadryad.org/stash/dataset/doi:10.5061/dryad.g1jwstqv4

Stable carbon (δ13C) and nitrogen (δ15N) isotope analysis was conducted on modern and archaeological polar bear bone collagen from the Canadian Arctic Archipelago to investigate potential changes in polar bear foraging ecology over four millennia. Polar bear δ13C values showed a significant decline in the modern samples relative to all archaeological time-bins, indicating a disruption in the sources of production that support the food web, occurring after the Industrial Revolution. The trophic structure, indicated through δ15N, remained unaltered throughout all time periods. The lower δ13C observed in the modern samples indicates a change in the relative importance of pelagic (supported by open-water phytoplankton) over sympagic (supported by sea ice-associated algae) primary production. The consistency in polar bear δ13C through the late Holocene includes climatic shifts such as the Medieval Warm Period (MWP, A.D. 950–1250) and the early stages of the Little Ice Age (LIA, A.D. 1300–1850). These findings ... : Ancient bone samples were collected from 35 polar bears from 10 archaeological sites in the region inhabited by the Lancaster Sound polar bear subpopulation. The archaeological samples came from pre-Dorset (N= 10; 4000–2800 BP), Dorset (N= 15; 1500–700 BP), and Thule (N= 10; 700–500 BP) sites, and consisted of several different anatomical elements but each element represented a distinct individual. The archaeological samples could not be sexed or aged. Modern bone samples (N= 11; 1998–2007 CE) were obtained from 11 individuals harvested within a 150 km radius of the communities of Ikpiarjuk (Arctic Bay), Aujuittuq (Grise Fiord), and Qausuittuq (Resolute) between 1998 and 2007. The modern samples consisted of polar bear bacula, collected as a mandatory sample by subsistence hunters. The modern samples were, therefore, male and ranged in age from three to 8-years-old. For the archaeological specimens, chunks of bone weighing ~200 mg were sampled using an NSK dental drill equipped with a diamond-tipped cutting ...