A Disturbing Whale Watch in Northwest
Marla Cone / LA Times 16feb01
Washington-area orcas, riddled with toxic PCBs, may be headed for the endangered-species list.
VICTORIA,
Canada -- The orca is a master predator. He glides like a torpedo, his
6-foot dorsal fin slicing through the surface of the sea. He hunts down a seal,
rams it repeatedly with his tail and drowns it.
These wolves of the sea stand unrivaled at the top
of the food web. But their rank in the ocean's hierarchy has given them another
extraordinary--and perilous--distinction:
They appear to be the most contaminated animals on
Earth.
The concentrations of industrial chemicals in
orcas, or killer whales, off Washington state and Vancouver Island are the
highest found in any living mammal, according to marine scientists. The poisons,
subtle but insidious, have built up in their bodies to dangerously high levels.
Stars of Hollywood films and marine amusement
parks, these black-and-white creatures are icons of the Pacific Northwest and
British Columbia. On a typical summer day, hundreds of tourists and boaters set
sail in hopes of spotting them.
Lately, though, there have been more
whale-watching vessels than whales plying the picturesque waters between Seattle
and Victoria.
The region's famed orca pods are shrinking.
Government officials now say there is a strong chance that these descendants of
Shamu, revered in native mythology as supernatural in their survival skills,
could be named an endangered species.
The region's killer whales have been dying at a
higher rate in the last five years, most disappearing without a trace. Nearly
half of their calves die within months of their births.
Scientists wonder if the industrial poisons
accumulating in their bodies are beginning to take a toll on their survival,
impairing their ability to fight disease and to reproduce successfully.
Or perhaps the Pacific Northwest's whales,
surrounded by nature lovers in yachts, kayaks and motorboats, are falling victim
to the stresses of their own popularity. The decline in salmon--a diet staple
for many orca pods--also may be harming them. Most likely, scientists say, the
orcas are being harmed by a combination of the urban threats they face.
Because a generation of orcas spans 10 to 15
years, researchers warn that it is too early to tell whether the recent
population decline is a temporary dip or a worrisome trend. In fact, this winter
showed a promising development: three new calves, bringing the total population
of the resident pods that frequent the San Juan Islands to 84.
But environmentalists worry that, if they wait for
scientists to decipher the trends, it could be too late to save the whales.
Long-lived, elusive and intelligent, these animals
have no predators. Nothing at sea is capable of killing a killer whale.
Except a human being.
Alarmingly High Contamination Levels
In the seaside town of Sidney, at the Canadian
government's Institute of Ocean Sciences, Peter Ross opened a long-forgotten
file one day in 1996.
He scanned the columns of data inside, and a
number caught his eye.
250 parts per million.
At first, he didn't believe it. These were the
worst concentrations of PCBs, or polychlorinated biphenyls, he had ever seen.
And they came from live killer whales swimming in the scenic waters off
Vancouver Island.
"My jaw dropped," Ross said. "I
said, these animals are really hot."
Ross decided to investigate. He pulled the blubber
biopsies of 30 more whales from a laboratory freezer and tested them for PCBs.
Ross, one of the world's foremost experts in
marine mammal contamination, had reason to worry about the whales. While working
in Europe a few years earlier, he had proved that PCBs weaken the immune systems
of harbor seals. Animals with compromised immunity are more likely to become ill
and die when exposed to disease or infections. European harbor seals experienced
a massive die-off in 1988.
Ross realized, though, that the killer whales off
British Columbia and Washington state made Europe's seals look pristine.
His research has shown that male killer whales
contain as much as 15 times more contamination than the seals that suffered
suppressed immunity.
At those concentrations, the whales "greatly
exceeded many toxic thresholds for mammals," Ross said. Disruption of the
whales' immune systems and reproduction is likely, since, he said, there is no
reason to believe that PCBs' effects on whales are different from effects on
seals.
Environmental agencies have known for years that
the Seattle area's Puget Sound is tainted with PCBs. But no one had suspected
that the poison was harming the killer whales because the San Juan Islands,
where they mostly live, are miles away from any industrial dumps.
"The concentrations in the orcas are
surprising, in part because they visit the Seattle area and other urban bays
infrequently," said Scott Redman, science coordinator of the Puget Sound
Water Quality Action Team, an arm of Washington state government. "Most of
their fish come from less contaminated areas."
Indeed, the local PCB contamination is by no means
extraordinary.
"Puget Sound is about average for a polluted
urban area," said Alan Mearns, a senior scientist at the National Oceanic
and Atmospheric Administration, which monitors pollutants in mussels. Santa
Monica Bay is just as contaminated, and San Francisco Bay's levels are twice as
high, Mearns said.
It turns out, however, that where the orcas live
does not determine how contaminated they are.
"It has nothing to do with how close you are
to the pollution source, but how high you are on the food chain," Ross
said.
Worldwide, the ocean floor has become the final
resting point for PCBs--long-lasting chemicals that were widely used as
electrical transformer oils and hydraulic fluids until banned in the United
States in 1977. PCBs enter the food web from the bottom up, accumulating in the
fatty tissues of animals. Animals low on the food chain may accumulate small
amounts. As predators consume those animals, they end up with much higher
concentrations in their tissues.
Killer whales carry such extraordinary loads of
chemicals because the animals they prey on are high on the food web and because
the whales consume so much--200 pounds a day.
Also, the longer an animal lives, the more
contamination it stores. Some of the region's killer whales were born before
World War I.
"They are like sponges that essentially soak
these chemicals up," Ross said.
Two types of pods frequent the waters around the
San Juan Islands. The "transients," which prey mostly on seals and sea
lions, are the most highly contaminated whales. The "residents" eat
only fish--mostly chinook salmon. The two types are genetically distinct, rarely
mingling and never switching diets.
For each level up the food web, the concentration
of pollutants in animals' tissues can rise tenfold, even twentyfold.
A herring may carry only 1 part per million of
PCBs, but the seals that eat that herring may contain 20 ppm and transient
killer whales that eat those seals have levels as high as 250 ppm. Fish-eating
resident killer whales also are highly contaminated because salmon are high on
the food web.
Male orcas carry the chemicals their entire lives,
which could explain why they live only half as long as females. Through their
milk, the mothers pass a lifetime dose of the compounds into their firstborn
calves.
"Cetaceans are vulnerable to accumulating
large quantities of these chemicals. They aren't able to get rid of them very
easily," said Walter Jarman, a University of Utah expert in pollutant
concentrations.
The killer whales apparently are getting the
chemicals from salmon and seals. But where, officials wonder, are the salmon and
seals picking them up?
Some of the PCBs clearly come from local waters,
where industrial and port operations deposited the chemicals in the years before
they were banned. But Asia also is probably contributing to the Pacific
Northwest's problem. Airborne contaminants blow from China to North America in
about a week. Salmon also probably pick PCBs up from Asia when they migrate into
the North Pacific.
Alaska's killer whales also are highly
contaminated, even though there are no local dumps or sources, said Craig Matkin,
a scientist with the North Gulf Oceanic Society.
In the waters off Seattle and Victoria, killer
whales aren't the only top-level feeders.
Human beings are, too.
People who regularly consume salmon or sole from
Puget Sound face several health problems from the PCBs, including an elevated
cancer risk. That has prompted Washington state officials to begin studying
whether health warnings are needed regarding eating Puget Sound salmon and other
fish.
Eating two ounces per day, which is average for
recreational anglers, increases cancer risk by one cancer for every 1,000 to
100,000 people exposed, according to a 1998 Puget Sound update by state
officials. Government regulatory officials usually worry about cancer risks
higher than one in 1 million.
Because salmon is such a precious commodity in the
region, the PCBs could become an explosive issue.
"The orca is an indicator of what could be
affecting human health as well," said Caitlin Cormier of the Washington
Department of Ecology. "It becomes very personal because we're high up on
the food chain, too."
Death Rate Has Risen Among Resident Orcas
Individually, the orcas off Washington and
Vancouver Island seem robust and healthy.
But experts have noticed some disturbing trends.
The death rate has climbed in the last five years
among the heavily studied three resident pods that frequent the San Juan
Islands. The population peaked at 99 animals in 1995, but now 84 are left--a 15%
decline in five years, according to the Center for Whale Research on San Juan
Island.
Transient whales are more highly contaminated but
also more mobile, making precise population counts difficult. The current
population estimate is around 220.
What is killing the resident whales remains
unproved. "Usually the animals just disappear. We rarely recover
carcasses," said Graeme Ellis, a researcher at Canada's Department of
Fisheries and Oceans who has been studying the region's killer whales since the
1970s.
About 42% of calves in the resident pods die
during their initial months, said John Ford, director of marine mammal research
at the Vancouver Aquarium. Some females give birth successfully every few years
while others produce no calves at all.
The southern population, around the San Juan
Islands, is much smaller than that of northern residents, which live in remote
Canadian waters and are less contaminated. The southern population also produces
fewer calves.
PCBs block formation of vitamin A, a hormone.
Calves are hit with a large dose in their mothers' milk just at the time they
need vitamin A to develop normally. So calf survival and calving rates "are
the kinds of things that might be affected" by PCB contamination, Ellis
said.
Whale populations also may not have fully
recovered from the effects of marine parks and aquariums, which removed 48 of
the region's young animals in the 1960s and '70s, leaving a 15-year gap in
calving.
Based on the recent population trends, U.S.
environmental groups will soon petition the National Marine Fisheries Service to
declare the resident whales endangered.
Doug DeMaster, a marine mammal expert at the
fisheries service, says there is a 50-50 chance that the agency will list the
orcas as endangered, which would then require the service to decide on steps to
protect the animals.
"There's certainly concern. They [the pods]
are small and declining," DeMaster said. "Contaminants are high--high
enough at least in lab animals to compromise immunity. There's also a lack of
salmon and there are threats from whale watching. These things are all
potentially problematic for them."
What worries researchers is the experience of
other marine mammal populations that have been heavily contaminated with PCBs.
Until the orca discovery, scientists had thought
that beluga whales off Quebec, which are stricken with tumors and reproductive
problems, were the world's most chemical-laden marine mammals.
The only animals known to contain more PCBs than
the Pacific Northwest's orcas are dead--Mediterranean dolphins that died en
masse from a virus epidemic.
The fates of the dolphins, belugas and the
European harbor seals that Peter Ross studied could be a warning for orcas. With
PCBs known to weaken animals' immune systems, could a mass die-off be a mere
virus away?
Whale Watchers May Be Adding Stress
Life can be stressful for the region's orcas, and
not just because of industrial chemicals.
On a sunny Saturday afternoon, Kari Koski is
navigating a boat around the San Juan Islands, the Pacific Northwest's most
popular whale watching destination.
But Koski is not here to watch the whales. She is
here to watch the people who are watching the whales.
Spotting a boater headed toward a pod of killer
whales, she picks up her megaphone.
"Please shut off your engines and let the
whales pass you," she says.
Within minutes, she sees another private boat
maneuvering too close.
"Vessel Cygnet," she says into the
megaphone. "Make sure you stay at least 100 yards away and go slowly while
traveling with the whales. Thank you."
Koski is a coordinator for the Whale Museum, which
patrols the crowded waters around the San Juan Islands to ensure commercial and
private boaters don't harass the whales.
Biologists are concerned that the traffic, which
exploded in the 1990s, may be stressing the whales, contributing to the
reduction in their survival rates. Boats could be obstacles to their hunting and
the engine noise could disrupt their communication.
Most whale-watching companies have agreed to
follow guidelines set in recent years by the Whale Museum. Boat operators say
they are, for the most part, sensitive to the animals and able to police
themselves. They fear that their industry is a scapegoat for the problems facing
the orcas when there is no evidence they are harming the animals.
Still, the museum's Soundwatch crew each year
detects more than 600 violations by the companies of voluntary guidelines that
most whale-watching outfits have agreed to. The flotilla of private sailors and
kayakers who sometimes surround whales in the narrow straits commit many more.
Few other sea creatures in recent history have
come into such close contact with so many people.
By all accounts, the region's killer whales, once
the epitome of wild, have become urban dwellers.
Orca Facts
Common name: Killer whale
Scientific name: Orcinus orca
Adult weight: 3,000 to 12,000 pounds
Adult length: 16 to 32 feet
Lifespan: About 50 years for females, 30 years for
males
Speed: Up to 30 mph
Habitat: All oceans
Calving: Every 3 to 5 years, but sometimes at
intervals of as long as 10 years.
Social structure: Killer whales live in pods. In
the Pacific Northwest, they are divided into transients and residents that do
not interact and have different lifestyles.
Diet: About 200 pounds of meat a day. Residents
eat fish. Transients eat marine mammals, mostly seals.
Population off Washington/British Columbia: 84
residents and about 220 transients
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