File/Telegraph-Journal    Right whales found off Grand Manan Island are regularly exposed to toxins from their food source, scientists report.

Right whales eating contaminated zooplankton
ENVIRONMENT: Toxins present, say scientists studying off Grand Manan

BY BRUCE BARTLETT
Telegraph-Journal
January 17/03

    The toxin that causes paralytic shellfish poisoning may also be contributing to the declining North Atlantic right whale population.
    Scientists from the University of Rhode Island doing research off Grand Manan Island have found that right whales are regularly exposed to the toxins causing paralytic poisoning by eating contaminated zooplankton.
   "We have found that the zooplankton that the right whales are feeding on have significant levels of PSP toxin in them," Dr. Edward Durban said Monday.
   It is estimated that only 300 of the whales are left in the world. They travel to the Bay of Fundy late every summer and spend a few months feeding in the area.
    The team led by "Mr. Durban recently published its findings in the journal Harmful Algae showing that the whales could be ingesting enough of the toxin to affect their breathing and how deep they can dive.
   Limits on diving ability could reduce how much food they can consume and ultimately have an impact on reproduction abilities, he said.
   The toxin in the red tide algae stops nerves from functioning.
    The zooplankton, which are a preferred source of food for the right whales, are picking up the toxin from the algae that contaminates clam flats around the Bay of Fundy.
   Humans who eat contaminated shellfish experience muscle weakness. Higher doses can result in death when breathing shuts down because of the nerve toxin.
   The study was a collaborative effort using information from other studies that showed how deep the whales were diving to feed.
   "They were feeding at a very specific depth, about 140 metres, and there was a very dense layer of zooplankton at that level," he said.
   The Rhode Island team was able to collect samples of zooplankton from that part of the ocean and measure the toxins in the organisms.
   An estimate of how much toxin the whales were ingesting was made based on the concentration of it in the zooplankton combined with how long the whales spent feeding in the area.

We don't have specific
funding to go out and
investigate this further
at this point.

DR. EDWARD DURBAN
Scientist

   "It's a significant level," he said.
   The toxin is water soluble so it would not be stored in tissues but would have an affect on the whales during the time they feed on the contaminated plankton.
   The Rhode Island team would like to go to the next level to try to discover if there is a link between the health of the right whale population and the toxin from the red tide algae that gets into their food supply.
   "We don't have specific funding to go out and investigate this further at this point," he said.

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