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The food-web structure of the Arctic deep Canada Basin was investigated in summer 2002 using carbon and nitrogen stable isotope tracers. Overall food-web length of the range of organisms sampled occupied four trophic levels, based on 3.8‰ trophic level enrichment (d15N range: 5.3-17.7‰). It was, thus, 0.5-1 trophic levels longer than food webs in both Arctic shelf and temperate deep-sea systems. The food sources, pelagic particulate organic matter (POM) (d13C=-25.8‰, d15N=5.3‰) and ice POM (d13C=-26.9‰, d15N=4.1‰), were not significantly different. Organisms of all habitats, ice-associated, pelagic and benthic, covered a large range of d15N values. In general, ice-associated crustaceans (d15N range 4.6-12.4‰, mean 6.9‰) and pelagic species (d15N range 5.9-16.5, mean 11.5‰) were depleted relative to benthic invertebrates (d15N range 4.6-17.7‰, mean 13.2‰). The predominantly herbivorous and predatory sympagic and pelagic species constitute a shorter food chain that is based on fresh material produced in the water column. Many benthic invertebrates were deposit feeders, relying on largely refractory material. However, sufficient fresh phytodetritus appeared to arrive at the seafloor to support some benthic suspension and surface deposit feeders on a low trophic level (e.g., crinoids, cumaceans). The enriched signatures of benthic deposit feeders and predators may be a consequence of low primary production in the high Arctic and the subsequent high degree of reworking of organic material. [ABSTRACT FROM AUTHOR]