National Geographic : 1994 Jun
Bloated by death-and a full-term fetus-a beluga towed to Tadoussac, Canada, awaits autopsy by toxicol ogist Pierre Beland. Cause of death: unclear. One possi ble culprit: pollution. Of an endangered population of some 500 belugas in the St. Lawrence River-isolated as glaciers retreated in the last ice age- 15 wash ashore in an average year. Nearly all are heavily contaminated with a toxic stew of chemicals, which have come in part from farms, aluminum smelters (below left), and other indus tries along the river and its tributaries. "These animals could qualify as hazardous waste," says Bland. Among dozens of toxics in beluga flesh isthe pesticide mirex, banned since the 1970s but still found in eels from the Great Lakes, a common beluga meal. Of 68 whales autopsied since 1982, 40 percent had tumors; many suffered organ and reproductive problems. "We're building a catalog of oddities," says biologist Robert Michaud (below), who, with Nathalie Boudreau, checks photographs for scars that help identify belugas in the St. Lawrence population. Michaud is not hopeful that herd numbers will rise; other experts remain optimistic.