Saint Lawrence belugas program
Lesions and contaminants
Beluga whales were held up in the St Lawrence Estuary when the glaciers retreated from North America, more than ten thousands years ago. The waterway they now inhabit drains the most industrialized part of North America. Bacteria, virus, parasites, and cancer are the most frequent causes of death and diseases of beluga whales living in the St Lawrence Estuary. The tissues of these cetaceans are contaminated with high levels of industrial contaminants known to be carcinogenic and/or immunosuppressive in every animal species where they have been tested. These contaminants are probably related with the causes of death of these animals: cancer, infections with bacteria, virus and parasites, most of which are weak pathogens.
 |
Decomposed carcass of an immature (3-years old) male beluga. (At that age, beluga are gray). The white areas are the exposed dermis (the skin layer that normally underlies the epidermal layer). The grey epidermis has desquamated owing to postmortem changes. The lungs of this animal were badly damaged by parasites (nematodes and inflammation). This is an example where the direct cause of death can be determined by examining even a fairly decomposed carcass. |
@information
