Tests show no sign
of red tide in area where whales died
BY ALISON AULD
Scientists are reworking a theory that 17 whales died from eating toxic algae
off southwestern Nova Scotia, after early tests showed no signs of the lethal
red tide in the immediate area.
Preliminary findings show
the water and a certain fish species that the whales ate in the region near
George's Bank had no traces of the algae.
and Canadian scientists had suspected the fin, pilot and humpback whales became
exposed to the toxin through the water or the tonnes of krill they eat every
Still, the negative findings have raised the
possibility that the whales could have become contaminated in another region
and then died in the shallow area that straddles Canadian and U.S. waters.
"So the question is still there and we're continuing our
investigation to determine the cause," Jerry Conway, marine mammal adviser with
the Department of Fisheries and Oceans, said Friday.
"There is a probability that it is a toxic issue, but not
in the area where we found the whales."
are still awaiting results from a battery of other tests that could yield some
insight into the one of the largest whale die-offs in recent years.
The last time so many whales died this close together was
in 1987, when red tide killed 14 off the New England coast.
A key piece of information is where the whales were
before they died.
Officials with the U.S. federal
fisheries service were conducting tests on four of the animals' digestive
tracts to find out what they ate and if it was toxic.
Canadian marine mammal experts were also awaiting results
on the whales' blubber, which could show signs of toxins.
"We might be able to get from that whether there was a
contaminant, which could help figure out where they were," Teri Frady,
spokeswoman for the U.S. National Oceanic and Atmospheric Administration
Fisheries in the Northeast, said from Woods Hole, Mass.
Other agencies are tracking the locations of algae blooms
along the northeastern U.S. coast to see if they could be linked to the deaths.
A U.S. fishery patrol boat discovered four dead whales -
three humpbacks and one fin - at the end of July on the northeastern tip of
George's Bank, an underwater plateau that extends from Nova Scotia to Cape Cod.
They found several more humpbacks and a pilot whale over
the next few days before adding about a dozen more to the toll.
Mr. Conway said a patrol vessel is now searching for a
dead humpback that can be used for a necropsy, or animal autopsy.
They haven't yet recovered an intact animal and are
hoping a fuller examination will help pinpoint the cause.
The whale carcasses showed no sign of trauma, Ms. Frady
said, indicating they likely weren't hit by passing ships or entangled in
Both are common causes of death for most
Red tide is a naturally occurring part of
the food chain. Small quantities will not typically affect humans, but large
amounts can cause nausea, fever, paralysis and even death.
The toxin is more dangerous to whales because they
eat whole fish by the tonne.