Fatty acids in blubber of beluga whales (Delphinapterus leucas) and ringed seals (Phoca hispida) from the Mackenzie River Delta, Northwest Territories, Canada.

Abstract

In northern Canada, consumption of marine mammal blubber and other products provides important components of native diets. This report describes a study which assessed the fatty acid constituents of beluga whale and ringed seal blubber. Working with hunters in communities near the Mackenzie River delta, Northwest Territories, Canada, scientists acquired and preserved (frozen) samples of seal and whale blubber for chemical analysis at Mote Marine Laboratory, Sarasota, Florida. Those analyses involved gas chromatography-mass spectrometry of fatty acid picolinyl esters to confirm the fatty acid composition of samples. In each species, mono-unsaturated fatty acids predominate. Blubber of both species contains a variety and relatively high levels of omega-3 fatty acids; in fact, in some ringed seal specimens, the percent composition of all omega-3 fatty acids exceeds 35%. The most abundant omega-3 fatty acids in each species were eicosapentaenoic acid, docasahexaenoic acid, and docosapentaenoic acid, in that order. Omega-6 fatty acids were rather diverse, but were present in very low amounts in all samples. Omega-3 fatty acids have been suggested or shown to be important in treatment and/or prevention of many diseases including elevated blood pressure and cholesterol, heart disease, stroke, diabetes, arthritis, depression, and some cancers; thus, consumption by subsistence-based communities of beluga whales and ringed seals could provide important nutritional/health benefits for subsistence-based communities.