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Seabirds
The Decline and Fall of the Emperor Penguin?
CLIMATE CHANGE AND SHRINKING ICE THREATEN POLAR BIRD
by David Levin
Few things go together as naturally as ice and penguins. But sea ice in Antarctica is threatened, and therefore so are emperor penguins.
A
Antarctica where French scientists from French Polar Institute
t nearly four feet tall, the Emperor penguin is AntarcPaul Émile Victor have conducted penguin observations for
tica’s largest seabird—and thanks to films like “March
more than 50 years.
of the Penguins” and “Happy Feet,” it’s also one of the
“Long-term data are required, if you really want to study
continent’s most iconic. If global temperatures continue
the impact of climate variability on populations,” she said.
to rise, however, the large colony of emperor penguins in
“Antarctica is, on average, the windiest, driest, and coldest
Terre Adélie in East Antarctica may eventually disappear,
place on Earth. For this reason, it’s very hard to study emperor
according to a study led by researchers from the Woods Hole
penguin colonies. The only place we can study an entire colony
Oceanographic Institution (WHOI).
over their entire year’s cycle is in Terre Adélie, because there, the
The decline of those penguins is likely connected to a siscientific base is not far from the penguin colony.”
multaneous decline in Antarctic sea ice resulting from warming
“If you want to study the effects of climate on a partemperatures in the region, said Stephanie Jenouvrier, WHOI
ticular species, there are three pieces that you have to put
biologist and lead author of the study.
together,” said Hal Caswell, a mathematical biologist at
Unlike other seabirds, emperor penguins breed and raise
WHOI and collaborator on the paper.
their young almost exclusively on sea ice.
“The first is a description of the entire
If that ice breaks up and disappears early
life cycle of the organism, and how inin the breeding season, massive breeding
dividuals move through that life cycle.
failure may occur, she said. “As it is,
The second piece is how the cycle is
there’s a huge mortality rate just at the
affected by climate variables. And the
breeding stages of penguins’ life cycle,
crucial third piece is a prediction of
because only 50 percent of chicks survive
what those variables may look like in
to the end of the breeding season, and
the future, which involves collaborathen only half of those fledglings survive
tion with climate scientists.”
until the next year.”
Jenouvrier used results from various
Disappearing sea ice may also affect
climate models to determine how changthe penguins’ food source. The birds
es in sea ice might affect the emperor
feed primarily on fish, squid, and krill, a
—Stephanie Jenouvrier
penguin population at Terre Adélie. She
shrimplike animal, which in turn feeds
found that if greenhouse gas emissions continue to rise at levels
on tiny zooplankton, phytoplankton, and algae that grows on
similar to today—causing temperatures to rise and Antarctic
the underside of the ice. If the ice goes, Jenouvrier said, so too
sea ice to shrink—penguin population numbers will diminish
will the plankton, causing a ripple effect through the food web
slowly until about 2040, after which they would decline at
that may starve the various species that penguins rely on as prey.
a much steeper rate as sea ice coverage drops below a usable
To project how penguin populations may fare in the future,
threshold.
Jenouvrier’s team used data from climate models, sea ice fore“Our best projections show roughly 500 to 600 breeding
casts, and a demographic model that Jenouvrier created of the
pairs remaining by the year 2100. Today, the population size is
emperor penguin population at Terre Adélie, a coastal region of
Our best
projections
show only 500
to 600 breading
pairs by 2100.
16 Oceanus Magazine Vol. 50, No. 2, Summer 2013 | www.whoi.edu/oceanus
nce
made no claims to Antarctic territory (although Russia
and the United States have reserved the right to do so)
and they do not recognize the claims of the other
nations.
Bouvet Island
(NORWAY)
South Georgia and the
South Sandwich Islands
(administered by U.K.,
claimed by ARGENTINA)
Falkland Islands
(Islas Malvinas)
(administered by U.K.,
claimed by ARGENTINA)
BRITISH
CLAIM
Southern
Ocean
ARGENTINE
CLAIM
Orcadas
Scotia Sea
(ARGENTINA)
SOUTH ORKNEY
ISLANDS
NORWEGIAN CLAIM
SANAE IV
Neumayer
(SOUTH
AFRICA)
(GERMANY)
Novolazarevskaya
(RUSSIA)
Maitri
ARGENTINA
Ushuaia
area of
enlargement
Drake
Passage
Weddell Sea
Syowa (JAPAN)
Molodezhnaya
(RUSSIA)
Enderby
Land
Halley (U.K.)
Belgrano II
Mawson
(ARGENTINA)
Palmer
Land
90 W
70
Queen Maud Land
CHILE
CHILEAN
CLAIM
60
undefined limit
(INDIA)
SOUTH
SHETLAND
ISLANDS
P
50
Bellingshausen
Sea
Peter I Island
Ellsworth
Mac. Robertson
(AUSTRALIA)
Land
80
Ronne
Ice Shelf
Zhong Shan(CHINA)
Progress (RUSSIA)
Amery Ice Sh
Davis(AUST
Stephanie Jenouvrier/WHOI
South Pole
2800 m.
Peter Kimball/WHOI
Shac
Ice S
Terre Adélie
70
66
64
around 3,000 breeding pairs,” Jenouvrier said. The study was
South
published in June 2012 in the journal Global Change Biology.
Ross
P a cthei research
f i c on penguins. At Terre
Ice Shelf
Amundsen
Jenouvrier is continuing
80
Adélie, scientists are instituting
O c e aanneasier method of monitoringSea
the penguin population. “We putting what’s called a PIT (Passive Inductive Transponder) tag under the skin of the birds,”
Ross Sea
she said. “It’s like what we put in cats and dogs. We’ll be able
average minimum
extent of sea ice
to record the identity of each bird, so we will be able to know if
they are surviving
and
returning
to
the
colony.”
Argentina, Brazil, Chile, China, Poland,
Russia,
South
Korea, Uruguay
have
At the same
time,
Jenouvrier
has each
expanded
her research to
a station on King George Island.
Ant
arcti
explore climate change impacts on penguin colonies throughc C
Esperanza
ircle
out Antarctica.
(ARGENTINA)
60 century, we have already observed
“Over the last
the disapMarambio
Southern
(ARGENTINA)
Prat penguin
pearance of the Arturo
Dion Islets
colony,
close
to
the West
U.S. Library of Congress
Bernardo
Ocean
(CHILE)
O'Higgins
Antarctic Peninsula,”
Jenouvrier said.
“In 1948 and the 1970s,55
Z
E AL
Peter Kimball/WHOI
scientists recorded more than 150(CHILE)
breeding pairs there. By
A ND
CL A IM
1999, the population was down to just 20 pairs, and in 2009, it
had vanished entirely.” p
ta
An
An
tar
ct
(NEW ZEALAND)
(NEW ZEALAND)
Tasmania
Ho
SNARES ISLANDS
(NEW ZEALAND)
NEW
ZEALAND
(NEW ZEALAND)
Wellington
South Island
Christchurch
40
180
Sydney
North Island
68
64
AUCKLAND ISLANDS
50
CHATHAM ISLANDS
n
(AUSTRALIA)
Campbell
Island
30
Graham
Also collaborating
on the study were Christophe
Barbraud and Henri
Land
65
Palmer
Weimerskirch of the Centre d’Etudes
Biologiques de Chizé in France and 6
(U.S.)
0
Vernadsky
Julienne Stroeve and Mark Serreze of the National Snow and Ice Data
(UKRAINE)
Center; and Marika Holland Antarctic
from the National Center of Atmospheric
Larsen
Iceby
Shelf
Research in the United States.
Funding for the study was provided
the
Peninsula
WHOI Ocean Life Institute, the WHOI Arctic Research Initiative, and the
WHOI Access to the Sea program; the National Science Foundation, Agence
Southern
Martin
National de la Recherche
Biodiversité, the Institut Paul ÉmileSan
Victor,
the
70
(ARGENTINA)
Ocean Marie-Curie
15 Rothera
Alexander von Humboldt Foundation,
European
fellowship,
0
(U.K.)
and the Cooperative Institute for Research in Environmental
Sciences visiting fellowship.
Co
Macquarie Island
ic
62
Ci
rcl
e
60
ic
rct
At top, WHOI biologist Stephanie Jenouvrier readies a five-month-old
emperor penguin chick for tagging in Terre Adélie (center). Tags help
identify birds and track whether they return to the colony to breed.
Woods Hole Oceanographic Institution
17