Deaths of six right whales in Gulf of St. Lawrence still a mystery: officials

Marine mammal experts say full necropsies will be needed to figure out what caused the deaths of at least six North Atlantic right whales found floating in the Gulf of St. Lawrence.

Isabelle Elliott of the Fisheries Department says three of the whales have been tagged with satellite trackers, which should make it easier to find the drifting carcasses.

She says the number of dead whales could be higher than six, but they hope to have a firm number in the next few days.

Elliott says they are talking with a number of provinces as they look for somewhere to haul one or more of the massive mammals to shore for a post-mortem examination.

Aircraft and Canadian Coast Guard vessels are trying to track down the carcasses in the waters near the Magdalen Islands.

Experts say the string of deaths is ``catastrophic'' for the species and amounts to more than one per cent of the 500 North Atlantic right whales left.

Tonya Wimmer of the Marine Animal Response Society says collecting biological samples will be critical to determining what caused the deaths and hopefully prevent further losses.

So far, officials say they don't know if the whales died as the result of being hit by ships, or because of some kind of toxic algal bloom.