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By:Vince Stricherz
Like the proverbial canary in the coal mine, penguins
are sounding the alarm for potentially catastrophic changes
in the world's oceans, and the culprit isn't only climate
change, says a University of Washington conservation biologist.
Oil pollution, depletion of fisheries and rampant coastline
development that threatens breeding habitat for many penguin
species, along with Earth's warming climate, are leading
to rapid population declines among penguins, said Dee
Boersma, a University of Washington biology professor
and an authority on the flightless birds.
"Penguins are among those species that show us that
we are making fundamental changes to our world,"
she said. "The fate of all species is to go extinct,
but there are some species that go extinct before their
time and we are facing that possibility with some penguins."
In a new paper published in the July-August edition of
the journal BioScience, Boersma notes that there are 16
to 19 penguin species, and most penguins are at 43 geographical
sites, virtually all in the Southern Hemisphere. But for
most of these colonies, so little is known that even their
population trends are a mystery. The result is that few
people realized that many of them were experiencing sharp
population declines.
Boersma contends the birds actually serve as sentinels
for radically changing environment. She advocates a broad
international effort to check on the largest colonies
of each penguin species regularly– at least every
five years – to see how their populations are faring,
what the greatest threats seem to be and what the changes
mean for the health of the oceans.
"We have to be able to understand the world that
we live in and depend on," she said. "It is
the responsibility of governments to gather the information
that helps us understand and make it available, but if
they can't do it then we need non-governmental organizations
to step up."
For 25 years, working with the Wildlife Conservation
Society and UW colleagues, Boersma has studied the world's
largest breeding colony of Magellanic penguins at Punta
Tombo on the Atlantic coast of Argentina. That population
probably peaked at about 400,000 pairs between the late
1960s and early 1980s, and today is just half that total.
There are similar stories from other regions. African
penguins decreased from 1.5 million pairs a century ago
to just 63,000 pairs by 2005. The number of Galapagos
Islands penguins, the only species with a range that extends
into the Northern Hemisphere, has fallen to around 2,500
birds, about one-quarter what it was when Boersma first
studied the population in the 1970s.
The number of Adélie and Chinstrap penguins living
on the Antarctic Peninsula, the northernmost part of the
continent, has declined by 50 percent since the mid-1970s.
Other species in Africa, South America, Australia, New
Zealand, the Falklands Islands and Antarctica also have
suffered significant population declines, Boersma said.
She recounts watching in 2006 as climate anomalies wreaked
havoc on breeding of the same population of Emperor penguins
that was featured in the popular 2005 film "March
of the Penguins." The colony bred in the same location
as in other years, where the ice is protected from the
open sea and wind keeps snow from piling up and freezing
the eggs. But in September, with the chicks just more
than half-grown, the adults apparently sensed danger and
uncharacteristically marched the colony more than 3 miles
to different ice. The ice they chose remained intact the
longest, but in late September a strong storm broke up
the remaining ice and the penguin chicks were forced into
the water. While the adults could survive, the chicks
needed two more months of feather growth and buildup of
insulating fat to be independent. The likely result of
the climate anomaly, Boersma said, was a total colonywide
breeding failure that year.
Changing climate also appears to be key in the decline
of Galapagos penguins, she said. As the atmosphere and
ocean get warmer, El Niño Southern Oscillation
events, which affect weather patterns worldwide, seem
to occur with greater frequency. During those times, ocean
currents that carry the small fish that the penguins feed
on are pushed farther away from the islands and the birds
often starve or are left too weak to breed.
These problems raise the question of whether humans are
making it too difficult for other species to coexist,
Boersma said. Penguins in places like Argentina, the Falklands
and Africa run increasing risks of being fouled by oil,
either from ocean drilling or because of petroleum discharge
from passing ships. The birds' chances of getting oiled
are also increasing because in many cases they have to
forage much farther than before to find the prey on which
they feed.
"As the fish humans have traditionally eaten get
more and more scarce, we are fishing down the food chain
and now we are beginning to compete more directly with
smaller organisms for the food they depend on," she
said.
As the world's population continues to explode and more
and more people live in coastal areas, the negative effects
are growing for both marine and shore-based habitats used
by a variety of species. There is an urgent need to begin
monitoring those negative impacts, Boersma said.
"I don't think we can wait. In 1960 we had 3 billion
people in the world. Now it's 6.7 billion and it's expected
to be 8 billion by 2025," she said. "We've waited
a very long time. It's clear that humans have changed
the face of the Earth and we have changed the face of
the oceans, but we just can't see it. We've already waited
too long.
"The Discovery Channel and public television are
very popular for their nature programs, and those featuring
penguins are especially popular. But we don't want to
just have them in our television sets. We want to have
them out in the world."
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EurekAlert
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