AFP
A Magellanic penguin sleeps in Magdalena Island,
50 km from Punta Arenas, Chile.
Punta Arenasm Chile - Magdalena Island, located
near Chile's southern tip, is a natural paradise for tens of thousands
of penguins who come every year to breed.
But global warming could threaten the long-term
survival of the species, say experts at the island nature reserve in
the Strait of Magellan, about 50 kilometres from the city of Punta
Arenas. The island is home to 22 bird species - 11 which nest year-round and 11 seasonal visitors - including the Magellanic penguin. About 23 000 tourists a year make the
pilgrimage to Los Pinguinos Natural Monument, a protected area
comprising tiny Marta Island and windswept Magdalena Island.
The penguins' main predators are aggressive
seabirds called skuas and Dominican gulls, which feed off penguin eggs
and young, says Roberto Fernandez, a ranger at the site for the past
seven years.
And those predator populations are growing. “Right now, what we are seeing is summer
starting late, then lasting through into March. Climate change is
bringing about a rise in gull numbers, that is for sure,” monument
administrator Neftali Aroca told AFP. “You would have to undertake a long-term study
in order to link this increase with a reduction in the penguin
population but the forecast is that in the future, the penguins could be
at risk.”
The worrying prognosis seems to confirm alarm
bells sounded in January in a study published in the scientific journal
PLOS ONE, which indicated that extreme weather, such as unseasonal
warmth and heavy rainfall, may have killed off a considerable number of
young Magellanic penguins.
The study - conducted over a period of 27 years
in Argentina's Punta Tombo peninsula, the largest breeding ground for
the species - showed that 65 percent of the colony's young died annually
on average, 40 percent of them from hunger and seven percent owing to
the effects of climate change.
Each year, the penguins flee the cold to spend winter in the warmer waters off Brazil.
As soon as they are big enough to swim, they head off on a 4 000-kilometre odyssey from Magdalena Island to Brazil. They spend the Southern Hemisphere winter on
the coast of Brazil's southern Santa Catarina state - though they
sometimes make it as far up as Rio de Janeiro's beaches.
Come mid-August, they begin to head back, via
Uruguay and Argentina to the Strait of Magellan, the natural passage
between the Atlantic and Pacific oceans, and Magdalena Island. “Magellanic penguins come to the island to
complete their reproductive cycle,” explains Valeria Sanchez, who has
spent five years as a tour guide here. “They start arriving in September, as summer
approaches, to enjoy the longer days necessary to incubate their eggs
and look after their young.” The Magellanic penguins, who can live to 25, are monogamous, sharing their lives with just one partner.
First to arrive on Magdalena Island are the
males, who must seek out the burrowed nests dug the previous season and
make any necessary changes with whatever material they can find,
including stones and feathers, before attracting their mate. Around a fortnight later, the females arrive, and their keen partners sound a trumpet-like call to guide them to the nest.
The species tends to use the same burrow year after year to reproduce over a six-to-seven-month period. Following fertilisation, the females lay one or
two eggs. For the first 12 days, she will incubate them and not leave
them - even to eat.
Following their long fast, the mothers give way
to the males in order to feed. The couples then switch at roughly
fortnightly intervals until the end of the 40 to 45 day incubation
period ahead of hatching in around November.
During the first months of their lives, the
penguins' offspring are wholly dependent on their parents for food,
learning to swim and how to fend off predators.“Between February and March, they start to
leave the island - but this year they began leaving two or three weeks
earlier,” Sanchez said. “It seems they wanted to give themselves a head
start to go and see the World Cup in Brazil,” she joked, before
explaining that the young had simply hatched early this year. - AFP
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