Are living belugas as contaminated as dead belugas?
Everything we know so far about the contamination and health of St.Laurent belugas was obtained from the examination of stranded animals. One might ask whether these carcasses are representative of the population as a whole. Are the bodies of dead belugas more contaminated than those of belugas still swimming in the river?
To go through the looking glass
Since 1994, a biopsy program has been underway. Blubber samples obtained from a representative number of living, photo-identified individuals will enable scientists to study the level of contaminants in live belugas and compare it to that of stranded animals.
The first results show that, indeed, living belugas are also heavily contaminated. However, there are differences between dead and live animals, particularly in which chemicals are more abundant. The levels of these chemicals in live animals appear to be highly variable. These differences may originate from distinct metabolic processes in the target tissues (superficial as opposed to deep blubber). A biopsy allows us to obtain a sample from the superficial layer of blubber. It is therefore difficult to interpret biopsy results.
Department of Fisheries and Oceans Canada, Environment Canada, World Wildlife Fund Canada, Parks Canada, Ministère de l’Environnement et de la Faune du Québec, Fondation de la Faune du Québec and Croisières AML Cruises.
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