Scientists rule out
red tide in mystery kill of 17 whales
BY ALISON AULD
Scientists were scratching their heads Thursday after discovering that several
whales found in an area that straddles American and Canadian waters did not die
from exposure to a toxic algae as was previously thought.
Results showed that four of 17 dead whales had no traces
of red tide in their livers, urine, feces or stomachs, confounding researchers
who assumed the lethal toxin was behind the large die-off.
"These findings have made this an even bigger puzzle than
it was a week ago - we're back to Square l," Jerry Conway, marine mammal
adviser with the Department of Fisheries and Oceans, said in Halifax.
"There is no indication of any red tide in any of the
"The mystery continues".
Scientists in both countries have been conducting various
tests on samples taken from some of the 17 whales found in a shallow area off
southwestern Nova Scotia.
They had suspected the fin,
pilot and humpback whales became exposed to the toxin through the water or the
tonnes of krill they eat every day.
last week showed the water and a certain fish species the whales ate in the
region near Georges Bank contained no traces of the algae.
Marine biologists were still awaiting results from other
tests that could yield some insight into one of the largest whale kills in
The last time so many whales died this
close together was in 1987 when red tide killed 14 off the New England coast.
The difficulty in solving the mystery is trying to
determine where the whales were before they died.
possible that they were exposed to a different contaminant in another area and
then succumbed to the toxin in the region where they were found.
Officials with the U.S. federal fisheries service were
also awaiting test results on the whales' blubber, which could show signs of
Teri Frady, spokeswoman for the U.S. National
Oceanic and Atmospheric Administration Fisheries in the Northeast, said those
findings were not yet available.
Other agencies were
tracking the locations of algae blooms along the northeastern U.S. coast to see
if they could be linked to the deaths.
Both Canadian and
American fisheries officials were using planes and boats to search the area for
another fresh carcass, which they would examine for more clues as to the cause
But they've been unable to find any of the
other whales, due partially to thick fog in the area.
U.S. fishery patrol boat discovered four dead whales - three humpbacks and one
fin - at the end of July on the northeastern tip of Georges Bank, an underwater
plateau that extends from Nova Scotia to Cape Cod.
found several more humpbacks and a pilot whale over the next few days before
adding about a dozen more to the toll.
carcasses showed no sign of trauma, indicating they likely weren't hit by
passing ships or entangled in fishing gear.
common causes of death for most whale species.
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.