By
Claire Doole 12/12/2005 - The
flaming orange and pink hues of the arctic sun spill across
the glassy waters of the fjord, granting the perfect conditions
for spotting killer whales, the ocean’s top predator.
Each year, hundreds of these whales, with their distinctive
black back and white underbelly, flock into Tysfjord and
Vestfjord off the north coast of Norway in the Barents
Sea between November and January to feed off migrating
herring.
Killer whales, or orcas, hunt everything
from fish and up — walruses, seals, sea lions, penguins,
squid, sea turtles, sharks, and even other kinds of whales.
Hunting in packs, they are often referred to as the “wolves
of the sea”.
But here in the Norwegian arctic,
these whales feed mainly on schools of fish that come
in close to shore. So close, that they have attracted
many tourist boats who can watch the whales from only
metres away. Whale watching is big business in an area
where incomes are comparatively low for oil-rich Norway.
But the season is short, with the sun setting in early
December and not rising again until a month later. Despite
the unpredictable weather, many still make the journey
to see these “killer” marine species.
However, Hans Wolkers, a straight
talking and resolute Dutchman has not come to whale watch
but to whale dart. A toxicologist with the Norwegian Polar
Institute, he is in Tysfjord to take biopsy samples of
orca blubber to test for toxic contamination. It is his
second visit and he is under no illusion about what he
is going to find.
“Several years ago I took away ten
samples for testing and the results were shocking,” Wolkers
explained. “All ten showed consistently high levels of
toxins. You name it, the whales had it – PCBs, pesticides
and at least one type of brominated flame retardant. They
are the most toxic mammal in the Arctic.”
Arctic sink
To date, it has been the polar bear that had the dubious
honour of being the most toxic mammal of the Arctic. But
Wolkers’ research shows that orcas outstrip the bear in
terms of pesticides and one type of brominated flame retardant,
in addition to the high levels of the toxic, persistent
chemicals PCBs (polychlorinated biphenyls).
According to Wolkers, the appearance
of a brominated flame retardant, a type of chemical found
in every day articles such as computers, is particularly
worrying because unlike PCBs and the most harmful pesticides,
most are not currently banned.
Although many PCBs and pesticides
have been phased out over the past twenty years and officially
banned since the Stockholm Convention on Persistent Organic
Pollutants (POPs) came into force in 2004, these persistent
pollutants, as their names suggest, are particularly difficult
to get rid of. In the Arctic, where temperatures are routinely
below freezing and the winters are steadfastly dark, they
take even longer to break down. To make matters worse,
due to the northerly direction of air and water currents,
most of Europe’s pollution ends up in the Arctic.
“The Arctic serves as a global environmental
indicator, an early warning system with which we can gauge
the health of the planet,” explained Rasmus Hansson, CEO
of WWF-Norway. “This remote region, far from the centres
of industrialization, has become the world’s toxic sink.”
Gazing at the fjords bathed in winter
sunlight, where snow-capped peaks rise sheer and straight
from the southern Barents Sea, it is difficult to believe
that the Arctic is so contaminated. However, the chemicals
transported by air and sea have for decades been contaminating
the top predators of the food chain.
“Killer whales are particularly vulnerable
to contaminants because they feed at the top of the food
chain and accumulate contaminates from the species they
prey on,” said Brettania Walker, a toxics officer with
WWF’s Arctic Programme. “These contaminants accumulate
in their blubber over time. As killer whales can live
up to 40 years, this means they can have very high contaminant
levels in their tissues.”
In pursuit of the toxic whale
When not testing herring — which is known to have some
levels of toxins but is still safe to eat — Wolkers spends
days at sea going after the killer whales. This is certainly
not as easy as catching herring as the whale spends most
of its time underwater, surfacing for less than a couple
of seconds at a time. In choppy Arctic waters, coupled
with bad lighting, the plume of spray from the whale’s
breathing hole is practically invisible to the untrained
eye. They are also extremely fast.
“A pod of whales travel on average
25 kilometres a day, but some can do 70 kilometres,” marvelled
Tiu Simila, a marine biologist who has been studying the
behaviour of the Tysfjord whales for the past 18 years.
“Streamlined like torpedoes, they can easily outrun a
motorboat.”
But, these factors don’t deter them
from their WWF-supported mission. Wolkers and his driver-cum-darter,
Odd Petter Hovde, a softly spoken Norwegian who also pilots
whale watching boats, have too much respect for the whales
to chase or confront them head on. They are biding their
time, scanning the horizon for a glimpse of the distinctive
upright dorsal fin.
“It is impossible to dart them when
they are travelling,” explained Hovde. “We look for the
birds circling overhead and then we know that the whales
are about to feed. That is the time when they are distracted.
That is the time to take aim.”
After several hours of false alarms
and mounting frustration with the whale watching boats
tracking them, Wolkers and Hovde finally came upon some
whales about to feed. Killer whales employ a range of
tactics to capture their herring prey, such as feeding
off the discarded catch of fishing boats. But one of the
most spectacular techniques they employ is “carousel feeding”
when they herd the herring into tight shoals close to
the surface and then stun them with their tails. The herring
are often so frightened they jump out of the water in
sheer panic. It is then that the feeding frenzy begins.
Picking up the biopsy gun, with the
assurance of a man who has spent time in the Norwegian
army, Hovde takes aim.
“The trick is to get within 20m and
dart it on the side under the dorsal fin as this is the
biggest surface area to hit,” Hovde explains.
Despite hours of maneuvering and coming
within range, the conditions were not right this trip
out. The dart, which is hollow, got entangled in the barrel
of the gun and despite frantic attempts to re-assemble,
it was too late. The whales had moved on.
However, patience and tenacity paid
off. At the end of two hard weeks, braving the cold and
fast fading light, Wolkers in the end collected blubber
samples from nine females and five males. This means he
can test for the toxins passed on from lactating mothers
to calves. Marine mammals produce milk that has 30 to
70 per cent fat so their young are exposed to high amounts
of contaminants at a vulnerable time in their development.
Whale detox
In addition to testing for all sorts of toxics cocktails
found in orcas, the tests will look for a particular brominated
flame retardant called Deca-BDE, used in plastics, electronic
goods and coatings for household products such as carpets
and other upholstered fabrics. They will also analyze
the blubber samples for vitamin A levels, which can indicate
whether the toxins are impacting on vital systems such
as hormones.
“Although Deca-BDE is a suspected
neurotoxin that could affect foetal development, it is
not banned anywhere in the world,” stressed WWF’s Brettania
Walker. “This new killer whale research underlines the
need for all hazardous chemicals to be replaced with safer
alternatives when they are available.”
WWF is currently campaigning for EU
legislation known as REACH (Registration, Evaluation and
Authorization of Chemicals) which would lead to the identification
and phasing out of the most harmful chemicals. The current
EU chemical regulatory system, similar to others around
the world, considers chemicals “safe until proven otherwise”.
According to Walker, REACH should
have an impact not just in Europe but also worldwide as
chemical imports would have to meet high safety standards.
While it is known that PCB’s, pesticides and brominated
flame retardants can affect the nervous, hormone and immune
systems of people, little is known about the impact of
these chemicals on the health of the killer whale and
other marine species.
Recent studies have shown that concentrations
of brominated flame retardants are already doubling their
concentrations in the environment every five years. Time
is of the essence to find out more about these bio-accumulating
toxins before it’s too late.
“As the migratory pattern of the herring
changes, the whales have begun to move offshore into deeper
waters,” noted Tiu Simila. “This means we will soon lose
an opportunity to find out more about their behaviour
and the impact that contamination is having on their health.”
Since the killer whales first came
to Tysfjord, they have given us an unprecedented glimpse
into their natural world. Unfortunately, our parting gift
to them, as they move back to the ocean, is more of a
poisoned chalice, a toxic burden whose lethal consequences
are not yet known.
* Claire Doole is Head of Press at
WWF International
END NOTES:
• The Orca (Orcinus orca) is the largest
member of the dolphin family. It is found throughout the
world’s oceans, but tends to prefer the cooler, more productive
polar and temperate waters. Like all dolphins, orcas use
sophisticated biological sonar, called echolocation and
can swim up to 50kph and travel 120-160 kilometres per
day. Males can be up to 9.5m long and weigh in excess
of 6 tons. Females are smaller, reaching up to 8.5m and
weighing about 5 tons.
• The Stockholm Convention is a global
treaty to protect human health and the environment from
persistent organic pollutants (POPs); chemicals that remain
intact in the environment for long periods, become widely
distributed geographically, accumulate in the fatty tissue
of living organisms and are toxic to humans and wildlife.
POPs circulate globally and can cause damage wherever
they travel. In implementing the Convention, governments
will take measures to eliminate or restrict the production
and use of the selected POPs. |