Whales
Are Dying Off North America’s West Coast — And it Could Signal
Trouble Deep in the Ocean
Vice,
15
August, 2015
In
only one week, the corpses of four humpback whales have been found
along Canada's west coast, fueling questions of whether their deaths
are connected to a recent uptick of whale and other marine animal
deaths in Alaskan waters. So far scientists don't know what's causing
the deaths, but some believe they could be connected to warmer than
average ocean temperatures that have caused unusual and
potentially poisonous algae blooms.
The
carcasses of 23 large whales, including endangered humpback and
fin whales, were found in the western Gulf of Alaska last month,
according to researchers at the University of Alaska Fairbanks. Of
those, 18 are believed to be linked to a single event, although there
is no direct cause known at this time. The deaths are believed to
have occurred in late May or early June, based on the decomposition
of the mammals. An unusual number of walrus and seabird
carcasses have also been found near the dead fin whales, the
Washington Post reported,
though it's unclear whether the deaths are connected.
One
of the humpbacks found along the northern British Columbia
coast reportedly
haddeep
gashes on its tail, leading the people who found it to question
whether it died from being entangled, although it has also
been suggested that
the injuries may have been older and unrelated. A First Nations group
found it floating offshore, and towed it to land so it could be
examined.
It
will be a couple weeks before the necropsies of that humpback and
another also found in BC waters are done. No cause of death has been
determined for either at this time. The other two dead whales have
been spotted floating off the west coast of Vancouver Island.
Dead humpback
found this week, off northern BC coast, near Klemtu. Photo by Philip
Charles.
Researchers
are analyzing the bodies of whales found in Alaskan waters, too, and
some don't
think they'll ever know for sure what
happened. It's normal for scientists to see one dead fin whale every
two years, the Washington Post states, meaning this year's fin whale
die off is a big deal.
"The
cause is still a mystery," Briana Witteveen, research
assistant professor at the University of Alaska Fairbanks, told VICE
News in an email.
As
one marine ecosystem researcher tells VICE News, the whales found
bobbing in the water or washed up on the shores could potentially
have been killed by an algae bloom connected to warmer than normal
ocean temperatures.
"We
have very unusual things happening," explained Tom Okey, a
University of Victoria expert who researches the effects of climate
change on marine ecosystems in the Pacific. "We have this big
algae bloom, and some of those algae are toxic, and especially when
the whole system is out of whack like that, you can have the toxic
ones become very abundant. And so it is feasible, it is reasonable
that there could be a link."
Kate
Wynne, a marine mammal specialist for the University of Alaska Sea
Grant Program, told The Weather Channel that environmental toxins
were her "leading hypothesis", too.
Ocean
surface temperatures in the North Pacific are well above average,
with sea surface temperatures as high as 5.4 degrees Fahrenheit, or 3
degrees Celsius, warmer than normal. And the Gulf of Alaska is
currently home to a warmer-than-usual water zone known
as the "warm blob." Higher
than normal sea surface temperatures can lead to toxic algae blooms.
The
larger than usual algae bloom that has been identified in the Pacific
could be poisoning other animals, including sea lions.
Baleen
whales, meanwhile, feed low on the food chain, Okey said. They
eat phytoplankton,
also known as microalgae, which can become toxic to the organisms
that eat them.
And
the whale deaths could signal something even worse beneath the
ocean's surface.
"Carcasses
of whales are easy to see and easy to find," Okey said, "but
other species that may have succumbed to toxins or some other
disturbance either sink or are more difficult to see, so there might
be massive, potentially massive, ecological changes that are
happening in the Northeast Pacific."
Okey
did not hesitate to draw a possible connection between the variable
ocean temperature changes and long-term climate change.
"This
could be a glimpse into the kinds of changes and the things that
could happen with climate change," he told VICE News. "We
know that there is a longer term trend of climate change, and these
events here are very short term variability. It's climate variability
and oceanographic variability. We also know that there are longer
term trends with climate change, which will emerge out of the noise
as we move forward in time. But some of these massive changes that
are happening give us insight into what the future might look like
for the Gulf of Alaska and the whole Northeast Pacific."
Gashes
on dead humpback's tail. Photo by Philip Charles.
Once
severely endangered, the humpback whale population has recovered
somewhat since their hunting was banned in the 1960s, leading some
groups to question whether they should be removed from the endangered
species list, where they first appeared in 1970.
In
April, the NOAA suggested
classifying humpbacks differently and
breaking them into 14 groups based on where they reside. Following
petitions arguing the humpback populations in Alaska and Hawaii have
recovered, the NOAA proposed removing 10 of the 14 groups from the
endangered species list, Scientific
American reported.
The
Canadian government removed
the humpback from the threatened species list last
year because of its significant population increase. In the mid-1960s
there were about 1,500 humpbacks in the North Pacific, but
the latest estimates put the current population between 18,000 and
20,000.
Fin
whales are the second largest mammal on earth, smaller only than the
blue whale.According
to the NOAA,
there are no reliable population estimates of fin whales. Commercial
hunting of fin whales ended by 1987, except off the coast of
Greenland, the NOAA said.
A
fin whale lies dead on Kodiak Island, in Alaska, in a June photo by
Bree Witteveen, University of Alaska Fairbanks.
This makes me so sad.
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