Off the coast of Cape Town, Robben Island is home to African penguins, whose future is by no means assured.
(Ariadne Van Zandbergen / Africa Imagery)
Few places let you get as close to the raffish birds—many of which are endangered—as South Africa’s Robben Island
By
Charles Bergman
Smithsonian Magazine
The lives of penguins on South Africa’s Robben Island are defined
by the rhythms of their daily commute. Every morning, they parade down
penguin highways to the sea, and every evening they return to their
nests along the same paths, full of half-digested fish that they
regurgitate to their whining chicks.
Robben Island is best known as the site where Nelson Mandela was imprisoned.
(Christoph Fischer / Photoshelter)
I was crouched behind a camouflage net to avoid scaring skittish
birds on their way home after a long day of fishing. My job was to read
the numbers on flipper bands. Scientists have banded about 4,000 chicks
and 40,000 adult penguins in this area over the past 33 years to find
out how long they live and where they feed, swim and nest.
Eight penguins, not yet tagged, teetered on the crest of a
sloping rock face and stopped just a few feet away to soak up the last
of the sun. These are not the world’s most beautiful penguins. They
don’t have the aristocratic bearing and the polar mystique of the
emperor penguin. They’re not as brightly colored as the king penguin,
with its glowing gold neck and nape, probably the most beautiful of all
penguins. Nor do they have the shining yellow head feathers of the
crested species, the macaroni and rockhopper penguins.
The African penguin, though, is handsome in its own simple way. A
single band of black loops around its white belly and chest, from foot
to foot, like a horseshoe. White stripes curve around its black cheeks,
giving the bird the appearance of wearing a white hood. A few black
spots mark the chest, different for each bird. The only decorative flair
is a patch of pink skin from eye to beak.
The birds continued their hike home, heading inland to their
waiting chicks, which were already begging for food. I heard a cacophony
of braying as penguins still at the nest called out to guide their
mates home. A harsh and hoarse donkey sound, the call earned the birds
their former name: jackass penguins. Every night the island echoes with
tone-deaf serenades, sung to establish and affirm mating bonds. They
honk out a loud chorus, chests pumping like bellows and beaks pointed to
the sky. The penguins might seem operatic if their songs weren’t so
ridiculously unmusical.
Something about the daily migration captures the animals’ dignity
and comedy. They are so purposeful, so earnest, so serious in their
stiff-legged waddle, wings rigidly forward. Often as I watched, they
would hear a noise or see something startling, like a gull, and the
entire group would dissolve in a general panic, fleeing in all
directions, using their flippers like front legs, even running over each
other.
African penguins have not been celebrated in movies, but they
find themselves on center stage now as one of the world’s most
endangered penguins. Researchers have been studying penguins here since
the early 1980s, and their work has shed a harsh light on a species in
free fall, with a population down more than 95 percent in 100 years. “I
hate to say it,” says Richard Sherley, a biologist at the University of
Cape Town who now runs the Robben Island study, “but unless something
serious changes, the African penguin may be on its way out.”
Robben Island is best known as the site of the former
maximum-security prison that once held Nelson Mandela and other
anti-apartheid activists, and one morning I accompanied Sherley to the
dense acacia trees in front of the hulking structure, now a museum (see “A Monument to Courage,”).
Sherley fought through heavy brush to reach a young chick in its nest, a
hollow in the sand about the size of a kitchen sink. Flippers out and
oversize feet cocked upward, the penguin chick squirmed in Sherley’s
grip. He lifted it and handed it to me.
For sheer cuteness, the baby penguin was tough to top. It looked
more like a bottom-heavy stuffed toy than a living creature; it was
covered in a thick velour of down and was mostly gray except for its
white belly and bulging white cheeks. “Watch out for the beak,” Sherley said, bringing me back to the task at hand. “Oh, and the poop, too—a stream of hot fish soup.”
In my nearly two weeks with Sherley, he surveyed nests, conducted
penguin counts and rescued birds—not just penguins but also gannets,
cormorants and petrels—that looked sick or in trouble.
We put the penguin chick in a green bag, careful to avoid both
ends of the bird, and weighed it on a fish scale—about five pounds. Its
flippers were just over seven inches long. Through the morning, we
weighed and measured 21 chicks, part of a study on the condition and
growth rates of the babies. “To see if they’re properly nourished,”
Sherley explained.
He handed me the chick to put back in the nest. It was tough and
well-muscled, like a stocky Jack Russell terrier. I set it down near its
nest and it scurried to its nest-mate. They merged into a single,
indistinguishable pile of gray down.
One of the biggest misconceptions about penguins is that they
live on ice. Their name conjures up images of the South Pole and long
marches through the Antarctic winter. In fact, only 2 of the 17 penguin
species are exclusively Antarctic birds, and only 5 species can be found
there. The rest live throughout the Southern Hemisphere. One species,
the Galápagos penguin, ventures just north of the Equator.
The African penguin occurs from Namibia down the coast to the
cape of South Africa, mainly on offshore islands. Only four colonies are
on the mainland. In 1985, a bunch of penguins established a breeding
colony on a breathtaking beach near Simon’s Town, on False Bay, a short
drive from Cape Town. A boardwalk now allows hundreds of thousands of
tourists every year to enjoy the birds’ antics. They may be the most
urban penguins in the world.
The African penguin was the first kind of penguin documented in
European history. On November 22, 1497, an anonymous member of Vasco da
Gama’s crew recorded seeing “birds as big as ducks, but they cannot
fly.” He continued: “These birds, of whom we killed as many as we chose .
. . bray like asses.”
The encounter prefigured the exploitation of the penguins
throughout their range over the next several centuries by explorers,
whalers and settlers; they slaughtered the birds for food or collected
their eggs to eat. Others gathered the guano for fertilizer, a practice
that also removed soil and prevented penguins from digging burrows for
nests.
On Robben Island, there was so much hunting and harvesting that
the penguins disappeared by the late 1800s. They began to return only in
the 1980s, well after the island had been turned into a notorious
political prison and been made off-limits to hunters.
Overall, though, the African penguin made it into the 20th
century in good shape. “Early photographs show that penguins covered
their islands in unspeakable numbers,” Sherley told me. The decline is
so dramatic that it’s worth giving in some detail.
In 1910, the penguin population in all of Africa was between 1.5 million and 3 million.
Off the coast of Cape Town, Robben Island is home to African penguins, whose future is by no means assured.
(Ariadne Van Zandbergen / Africa Imagery)
In 1956, the population was estimated at 300,000 birds.
In 1993, that number was down to perhaps 140,000.
By 2009, the time of the most recent in-depth survey, there were about 81,000.
The scientific name of the African penguin is Spheniscus demersus,
or “plunging wedge,” referring to the bird’s superb swimming and diving
abilities. But it might just as well refer to the species’ plunging
population.
Eleven penguin species are classified as vulnerable or
endangered. The Humboldt penguin, which is found from Chile to Peru,
numbered more than a million birds in the 19th century. The population
now may be just 25,000. Northern rockhopper penguins, which live on a
few islands in the southern seas, have declined 90 percent in recent
decades.
Historically, the problems facing penguins seemed clear: hunting,
egg collecting, alien predators like cats and rats, and oil spills.
These problems still beset penguins, and each species faces its own
particular threats. The wreck of the ship MV Treasure in 2000,
for example, spilled 1,300 tons of petroleum near Robben Island, oiling
19,000 birds. The latest dangers are more elusive, more global and more
difficult to solve: overfishing, climate change and marine degradation.
African penguins are susceptible to nearly all these threats, and
Sherley warns they could be caught in an “extinction vortex.”
Dee Boersma, a penguin expert from the University of Washington,
has studied the Magellanic penguin in Argentina for about 30 years. She
says penguins are “marine sentinels,” indicators of the general state of
the world’s oceans. “Penguins are reflecting rapid changes in the
marine environment,” she writes, and their falling numbers suggest that,
so far, “people are doing a poor job of managing the oceans.”
Still, research on the African penguin has benefited the species.
The penguins had been forced to nest in the open, vulnerable to storms
and floods and predators like gulls, largely because the island’s soil
had been stripped by guano collectors. Researchers began building little
huts for the birds to nest in—penguin “igloos.” Sherley says “birds in
the artificial nest boxes breed more successfully than those in the
bushes or natural burrows on Robben Island.”
Of the world’s 17 penguin species, perhaps the most accessible are African penguins nesting on False Bay near Simon’s Town.
(Charles Bergman)
Another crucial advance came after the 2000 oil spill. Getting
oiled by a spill reduces a bird’s ability to rear chicks successfully
for the rest of its life, even when it has been professionally washed
and rehabilitated. But chicks hand-reared after a spill have fared as
well as normal chicks, perhaps even better—a finding that has catalyzed
increased efforts to take care of abandoned or imperiled chicks.
Flipper-banding studies have shown that protecting these penguins
is urgent. The survival rate in adults, which commonly live 10 to 14
years, has decreased by 22 percent since the early 2000s. “In long-lived
species like seabirds,” Sherley says, “decreased adult survivability is
pretty much a sure sign that something is seriously wrong.”
The adult male penguin on Sherley’s lap looked like a
black-and-white torpedo, fat and round and tapering to the pointed beak.
It also looked as if it could explode at any minute and bolt from his
grip. Sherley controlled it with both hands, one behind the bird’s head
and the other hugging it close to his body.
Biologist Kate Robinson from the University of Cape Town moved
quickly to attach a small recording device on its back. She used black
tape to secure the electronic backpack to the penguin’s feathers. It was
a GPS device that records location, depth of dives, temperature of the
water and other information. “We’ll retrieve the logger when he comes
back,” Robinson said.
Maps generated by such loggers have shown that these penguins
travel about 20 miles on their foraging trips and can swim as far as 100
miles round-trip. But much of the time they’re fishing close to the
colony. “They work their socks off to fish,” Sherley said.
Lately they’ve had to work much harder. The preferred prey of
African penguins—anchovies and sardines—has been disappearing in much of
the penguin’s range. The fish have moved some 250 miles to the
southeast. Bound to their nesting colonies, the penguins cannot follow
them. Studies by Robert Crawford of South Africa’s Department of
Environmental Affairs and Tourism show that the breeding success and the
survivability of these penguins are directly connected to the
availability of anchovies and sardines.
What has caused the fish to move has proved elusive. “I suspect a
suite of factors,” Crawford said. “That includes environmental change.
There’s plenty of evidence of change in the Benguela Current.” The
current carries frigid, nutrient-rich waters from Antarctica, and it has
warmed at the southern and northern edges and shifted to the east.
Another problem may be overfishing. Over the past six decades,
South African fishermen have harvested about 400,000 tons of sardines
annually in the purse seine fishery. One study puts the local fish
“carrying capacity” (a measure of potential population) at only 10 to 20
percent of what it was a century ago.
The South African government recently started restricting fishing
temporarily in areas near breeding colonies. It’s an experiment to see
whether protecting marine areas can improve seabird populations. “A few
years ago, there was no consideration of the impact of the fishery on
seabirds,” says Sherley. “Today, the possibility that the fishery may be
contributing to the declines is being taken seriously.”
When I came to Robben Island, I expected to be won over by the
penguins. They did not disappoint. I could watch them endlessly. Perhaps
their charm derives from their similarity to us. More than any other
bird, they seem such comical little versions of ourselves. “We laughed
at the colony of penguins,” Mandela recalled in his autobiography, Long Walk to Freedom, “which resembled a brigade of clumsy flat-footed soldiers” marching across the beach.
Although I knew African penguins were in decline, I did not
expect to hear such open talk among biologists about extinction.
Penguins are improbable birds. None of us would have imagined such a
creature if we had not seen one. But it’s even more unthinkable that we
might lose them.Zandbergen / Africa Imagery)
Richard Sherley and friend.
(Charles Bergman)
One morning on the island, we found three chicks that were
clearly emaciated, their breastbones protruding from their white chests.
Two were nest-mates, and little; the third was older, partially
fledged. Sherley decided they had to be rescued. He caught them, put
them all in a box with air holes and took them back to the research
station. There he gave each an emergency tube feeding. In the afternoon,
the chicks took the ferry to Cape Town, where they were met by people
from the Southern African Foundation for the Conservation of Coastal
Birds. They specialize in rehabilitating and releasing seabirds.
Showing me a graph of normal chick development, Sherley said
these chicks were way below normal. “They’d die for sure if we had not
rescued them.” We rescued five penguins over 11 days, including one
anemic adult.
When I left Robben Island, I visited the conservation center in
Cape Town to learn more about what it does and to see what became of our
rescued chicks. Nola Parsons, a veterinarian, was holding an endangered
northern rockhopper penguin that had washed up on a nearby beach, way
out of its normal range.
“Two of your chicks made it,” she told me, and took me to see
them. After nearly two weeks, they’d put on weight and had fledged into
their “baby blue” plumage. The adult penguin was still alive, too. But
two of our chicks had died. “Just too far gone,” Parsons said.
As we talked, a group of schoolchildren arrived, eager to learn about penguins. “So many seabirds are in trouble, more than most birds,” Parsons
said. “Penguins may be our best ambassadors for them, and for the
oceans.”
Charles Bergman wrote about wildlife trafficking in South America for the December 2009 Smithsonian.
The Penguin Camera is located on Torgersen Island (64°46’S, 64°04’W), off the coast of Anvers Island and less than a mile from Palmer Station. Torgersen Island is home to a colony of Adélie penguins numbering approximately 2,500. This camera is seasonal and operates primarily from October to February, the Adélie breeding season. The camera is solar-powered and may sometimes experience brief outages due to inclement weather. School classrooms and other educational demonstrations will often take control of the camera, moving it to gain better views of the colony.
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