I
suspect there are as many lies and omissions in this as there is
truth. One cause – radiation from Fukushima – is taboo.
Orcas
of the Pacific Northwest Are Starving and Disappearing
9
July, 2018
SEATTLE
— For the last three years, not one calf has been born to the
dwindling pods of black-and-white killer whales spouting geysers of
mist off the coast in the Pacific Northwest.
Normally
four or five calves would be born each year among this fairly unique
urban population of whales — pods named J, K and L. But most
recently, the number of orcas here has dwindled to just 75, a
30-year-low in what seems to be an inexorable, perplexing decline.
Listed
as endangered since 2005, the orcas are essentially starving, as
their primary prey, the Chinook, or king salmon, are dying off. Just
last month, another one of the Southern Resident killer whales —
one nicknamed “Crewser” that hadn’t been seen since last
November — was presumed dead by the Center for Whale Research.
In
March, Gov. Jay Inslee issued an executive order directing state
agencies to do more to protect the whales, and in May he convened the
Southern Resident Orca Task Force, a group of state, tribal,
provincial and federal officials, to devise ways to stem the loss of
the beloved regional creature. “I believe we have orcas in our soul
in this state,” he said. At another point, he wrote of the whales
and Chinook salmon that “the impacts of letting these two species
disappear would be felt for generations.”
SEATTLE
— For the last three years, not one calf has been born to the
dwindling pods of black-and-white killer whales spouting geysers of
mist off the coast in the Pacific Northwest.
Normally
four or five calves would be born each year among this fairly unique
urban population of whales — pods named J, K and L. But most
recently, the number of orcas here has dwindled to just 75, a
30-year-low in what seems to be an inexorable, perplexing decline.
Listed
as endangered since 2005, the orcas are essentially starving, as
their primary prey, the Chinook, or king salmon, are dying off. Just
last month, another one of the Southern Resident killer whales —
one nicknamed “Crewser” that hadn’t been seen since last
November — was presumed dead by the Center for Whale Research.
In
March, Gov. Jay Inslee issued an executive order directing state
agencies to do more to protect the whales, and in May he convened the
Southern Resident Orca Task Force, a group of state, tribal,
provincial and federal officials, to devise ways to stem the loss of
the beloved regional creature. “I believe we have orcas in our soul
in this state,” he said. At another point, he wrote of the whales
and Chinook salmon that “the impacts of letting these two species
disappear would be felt for generations.”
Much
is still unknown about the plight of these orcas, but biologists and
conservation managers have zeroed in on several main factors — and
they are all connected.
The
biggest contributing factor may be the disappearance of big king
salmon — fish more than 40 inches long. “They are Chinook salmon
specialists,” said Brad Hanson, team leader for recovery efforts
for the Northwest Fisheries Science Center here, part of NOAA. “If
they could, they would eat Chinook salmon 24/7.” Orcas gobble 30 a
day. Hunting enough smaller prey requires a lot more energy.
The
underwater world in the region is also getting noisier, especially an
area between the San Juan Islands and Vancouver Island called Haro
Strait. It is one of the orcas’ favorite foraging grounds in the
summer.
“It’s
also essentially a big rock ditch where sound bounces off. When you
add in commercial vessel traffic going to Vancouver, recreational
boaters and whale watching operations, it’s a pretty noisy place,”
Mr. Hanson said.
Researchers
are studying noise there now. They believe the cacophony of ship
traffic interferes with echolocation and makes it harder for the
whales to locate their prey and to communicate prey location among
themselves. It can also cause hearing loss.
In
recent years, officials have expanded the distance which vessels,
including whale watching boats and kayaks, must keep from the whales.
And there is a voluntary no-go zone near the San Juan Islands.
“Just
the presence of boats can cause the whales to spend less time
feeding,” said Lynne Barre, of NOAA Fisheries, recovery coordinator
for the orcas. “And it’s harder to communicate. They have to call
longer and louder when boats are nearby.”
Another
factor is the pollution in Puget Sound. Whales that live off the
coast of Seattle, Tacoma and other cities are effectively urban
whales buffeted by municipal and industrial waste, and the occasional
spillage from wastewater treatment plants into the ocean. Killer
whales carry some of the highest levels of pollution of any marine
animal.
Of
most concern are the lingering effects of chemicals and pesticides,
including the now banned DDT, as well as PCBs and PPDE, widely used
in flame retardants and found through the world. The pollutants
accumulate in salmon as they feed, and when the whales eat salmon
they also ingest PCBs at even higher levels.
“It’s
very lipophilic, which means it stays in the fat, and the females
transfer a huge proportion of the contaminant burden to their
offspring,” Dr. Hanson said. “About 85 percent gets transferred
to calves through lactation.”
And
while much of the pollution is from the region’s industrial past,
Boeing disclosed this spring that over the past five years it had
discharged highly toxic PCBs into the Duwamish River, which flows
into Puget Sound, thousands of times over the legal limit.
These
toxins suppress the whales’ immune systems, making them more
susceptible to disease. They can also impede reproduction. That may
be why tests show a high number of females who have become pregnant
have failed to calve.
However,
the decline of the whales can’t be pegged, experts say, to
contaminants alone. A separate population of transient whales near
here eat mammals that eat fish, and so consume concentrate
contaminants at even higher levels — many times as high as the
resident pods. Yet they are thriving, which has left scientists
scratching their heads. Global populations are robust as well.
One
possible scenario is that the dearth of salmon coupled with the
interference of engine noise, which can affect their immune system,
too, deprives the orcas of a sufficient diet. Their bodies then draw
on fat reserves, which are laced with chemicals that suppress their
immune system and reduce fecundity.
But
experts aren’t sure what is raising their mortality rate. Often,
when whales die, their carcasses sink or wash up onto remote beaches
and are hard to find and test.
In
recent years, researchers have been focusing on anthroponeses,
diseases that humans may be passing to wildlife. Scientists have
sailed out among the pods with a petri dish at the end of a 25-foot
long pole to pass through the mist that whales exhale and see what
they carry in their lungs. They found a range of pathogens that could
be from humans, including antibiotic resistant bacteria and
staphylococcus, which can cause pneumonia.
“It
doesn’t mean they are sick, we don’t have evidence for that,”
said Linda D. Rhodes, a research biologist expert in marine microbes
and toxins and part of the study. “It means they are being exposed.
Whether or not the whales get sick is a product of how much of it is
present in the environment and how well is the whale able to defend
itself.”
There
is deep concern that a fatal human or animal disease has, or will,
cross the species barrier and find its way into these
immuno-compromised killer whales. “I’ve had dreams about it at
night,” said Joseph K. Gaydos, a veterinarian with the SeaDoc
Society in Eastsound, Washington in the San Juan Islands, who studies
the southern residents. “Disease smolders in the environment but
can break out. If there were a highly virulent virus to come through
here it would take out a large part of the population and totally
stop recovery efforts.”
Disease
threats are myriad. A young killer whale died from a fungal infection
last year. Toxoplasmosis is a disease spread by parasites in the
feces of cats. It is one of the top threats to the Hawaiian monk
seal, killing eight of the remaining 1,400 since 2001. It’s not
known, though, to affect whales.
Canine
distemper from dogs is also a concern. It’s a morbillivirus, which
is an RNA rather than a DNA virus. Some 1,500 dolphins were killed by
a single outbreak of morbilliviruses on the East Coast several years
ago.
“RNA
viruses can mutate rapidly and cross species lines,” Dr. Gaydos
said.
Steps
are being planned to help the whales persevere. More Chinook salmon
are being reared in hatcheries as whale food, but that is far from a
certain fix.
In
the end trying to maintain a population of whales in the shadow of
one of the fastest growing cities in the country may not be possible.
“It’s
an ecosystem-wide problem,” Dr. Hanson said. “Things are out of
whack and we have to get them back to where we can sustain killer
whales. And the clock is ticking.”
Losing
the charismatic, intelligent animals with the distinctive
black-and-white “paint job” and permanent smile would be a blow
to the area.
“There
would be a great sense of loss,” Dr. Rhodes said. “They are such
a part of our identity here. It would be a real sense of failure.”
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