TY - JOUR T1 - The Canadian Beaufort Shelf trophic structure: evaluating an ecosystem modelling approach by comparison with observed stable isotopic structure A1 - Hoover,Carie A1 - Giraldo,Carolina A1 - Ehrman,Ashley A1 - Suchy,Karyn D. A1 - Macphee,Shannon A. A1 - Brewster,Jasmine D A1 - Reist,Jim D. A1 - Power,Michael A1 - Swanson,Heidi A1 - Loseto,Lisa L. AD - Univ Manitoba, Ctr Earth Observat Sci, Winnipeg, MB R3T 2N2, Canada AD - Fisheries & Oceans Canada, Cent & Arctic Reg, 501 Univ Crescent, Winnipeg, MB R3T 2N6, Canada AD - IFREMER, HMMN, Ctr Manche Mer Nord, BP 669, F-62321 Boulogne Sur Mer, France AD - Univ Victoria, Dept Geog, Victoria, BC V8W 2Y2, Canada AD - Univ Waterloo, Biol Dept, 200 Univ Ave W, Waterloo, ON N2L 3G1, Canada UR - https://archimer.ifremer.fr/doc/00709/82155/ DO - 10.1139/AS-2020-0035 KW - Ecopath with Ecosim KW - stable isotopes of nitrogen KW - trophic level KW - marine ecosystem N2 - Climate-driven impacts on marine trophic pathways worldwide are compounded by sea-ice loss at northern latitudes. For the Arctic, current information describing food web linkages is fragmented, and there is a need for tools that can describe overarching trophic structure despite limited species-specific data. Here, we tested the ability of a mass-balanced ecosystem model (Ecopath with Ecosim, EwE) to reconstruct the trophic hierarchy of 31 groups, from primary producers to polar bears, in the Canadian Beaufort Sea continental shelf. Trophic level (TL) estimates from EwE were compared with those derived from two nitrogen stable isotope (SI) modelling approaches (SI linear and scaled) to assess EwE accuracy, using a dataset of 642 δ15N observations across 282 taxa. TLs from EwE were strongly, positively related to those from both SI models (R2 > 0.80). EwE performed well (within 0.2 TL) for groups with relatively well-known diets or for taxa characterized by fewer trophic connections (e.g., primary consumers). Performance was worse (> 0.5 TL) for species groups aggregated at coarse taxonomic levels, those with poorly documented diets, and for anadromous fishes. Comparisons with SI models suggested that the scaled approach can overestimate the TL of top predators if ecosystem-specific information is not considered. Y1 - 2022/03 PB - Canadian Science Publishing JF - Arctic Science SN - 2368-7460 VL - 8 IS - 1 SP - 292 EP - 312 ID - 82155 ER -