Newsletter / Blog
2013-01-03 Keeping track of penguins
Where do African
Penguins go when they’re not breeding? This may sound like the opening line to
a lame joke, but currently it’s a fascinating scientific question, the answers
to which could help stop the precipitous population decrease of this endangered
species.
Researchers from
BirdLife South Africa and the University
of Cape Town have a
better idea of how to answer that question. The Charl van der Merwe Trust and
the Mohammed bin Zayed Conservation Fund have provided funds for 20 satellite
trackers. The study, which is the first of its kind, tracked penguins using the
small, waterproof satellite transmitters. “This is the first time that anyone
has tracked adult African Penguins that have just completed a breeding cycle,”
says Dr Ross Wanless, Manager of the Seabird Division at BirdLife South Africa. Previous tracking studies have focused
almost exclusively on breeding penguins, because researchers can be sure that
they will return to their nests, which allows the retrieval of small but quite
pricey units. “With the advent of improved technology, satellite devices, which
can send data directly to our computers, are now small enough to attach to
penguins but still provide enough battery life to be useful” explains Dr
Wanless. Satellite trackers were famously used to track how quickly Peter,
Pamela and Percy, released at Port Elizabeth,
returned to the Western Cape
following the Treasure oil spill in 2000.
“The aim of the
project is to find out where the penguins go once they have finished breeding.
This is a crucial period because they need to fatten up to survive two weeks of
moult,” says Christina Moseley, BirdLife South Africa’s
Coastal Seabird Conservation Manager. During the moult, penguins stay on land,
don’t eat, and replace all their feathers. The lucky ones lose only half of
their body weight. “By knowing if they stay close to their breeding islands or
travel away from them, we can see if they are likely to come into competition
for food with the sardine and anchovy fishery and if implementing special
management areas will help” adds Ms Moseley.
In mid-September,
10 satellite trackers were deployed on penguins from the west coast, at Dassen Island,
with the help of CapeNature, who manage the island. In the east, SANParks, UCT
and BirdLife staff went to Bird Island in Nelson
Mandela Bay
and deployed the other 10 devices. “The birds went out to sea for about a month
and we can now report that most of them have made it safely back home” says Mr
Craig Harding, the UCT student who is leading the study. “There are a couple
that are a bit slower in getting back to their island but overall the project
has been a success,” he adds. The penguins on Dassen Island
travelled far from the island. One bird travelled north at 50 km/day for 10
days, almost to the border with Namibia.
Most went south and then east, as far as 540 km to Mossel Bay,
before returning to Dassen. The penguins from Bird
Island tended to stay closer to the
island, with the furthest travelling penguin going almost as far as East London, a distance of about 170 km. The team now
have the tricky task of trying to recover the satellite transmitters so they
can use them for further work, possibly to track penguins after they have
finished moulting.
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