Cliff and Doris Kolber
Nature - Travel - Photography
Antarctica newsletter #3: Cruising for Chicks
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Antarctica Newsletter #3
Cruising for Chicks
This newsletter is about is the
food chain at work in Antarctica. Predator birds, skuas and giant petrels, work hard to catch
their prey, the penguin chicks! Let's follow the struggle and
survival of one chick who avoided being an afternoon snack on Hannah Point.
Hannah Point in Antarctica
The
action at the rookery on Hannah
Point was so incredible
that the story needed its own book. We had
seen Skuas and Giant Petrels working at other rookeries to grab chicks but the
action at Hannah Point was a highlight of the entire
trip. We watched Skuas swoop down time
and again to pull chicks from under a parent in the nest. Some were successful and others were not. The birds at Hannah Point
were much more aggressive than we'd seen before. Life
as a penguin is not all peaches and cream.
As cute as penguin chicks are, they are also tasty treats to their
predators.
First
let's review the dynamics of Hannah
Point. It lies on the southern coast of Livingston Island,
which is part of the South
Shetland Island
chain. These islands are just north of
the Antarctica Peninsula,
and include King George Island,
where ten different countries have permanent research stations. To keep it in perspective, this archipelago
lies about 800 miles south of Argentina.
Hannah Point is a half moon bay that
slopes up to about 500 ft high. There
are all kinds of penguins and birds nesting here along with elepha nt
seals. There is no snow on Hannah Point
during the summer and in fact it is covered with green grass, called Antarctic
Hairgrass. This is the only grass that
grows in Antarctica. There are also mosses and lichen growing on
the ground and the rocks, which gives Hannah Point
a sub-tropical feeling. There is a beach on the far end of the bay with
fossils, and although a lot of people walked over there, we didn't make
it. We ended up at the penguin rookery
in the middle of the point where there were thousands of adult and chick Gentoo
and Chinstrap penguins, along with predator birds, Skuas and Giant Petrels, who
were cruising for chicks.
Cruising for Chicks
Penguin
chicks were gathered together in groups ("crèches") of 10 to 15 all over the
rookery. These are like day care
centers, with one adult penguin watching over the chicks while the other parents
go to sea for food. When the parents
return they find their chicks by calling to them . Even with tens of thousands of penguins in
the area, the chicks and parents recognize their own unique calls.
Among all this were nests with adults
watching overtheir newly hatched chicks.
And cruising overhead were the predator birds, the Skuas and Giant
Petrels, looking for nests to grab a "Chick-filet" lunch. Skuas will kill penguin chicks to get food for
their own chicks. That's because penguin
chicks are fed regurgitated seafood by their parents, and the Skuas will kill
the chick in order to harvest the chick's stomach for that food. This is the food chain at work, and it is
amazing to watch!
We
watched Skua after Skua dive bomb nests and try to grab chicks. They would work in teams of two. One Skua would land next to a nest and attack like he's after the chick. The parent
penguin would start screeching and chase the Skua away. While this is going on a second Skua would
swoop d own to grab the chick from the other side. Penguins pretty much know this will happen so
they stay alert to both sides. Most of
the time the penguin is successful. So
it took a while before we finally witnessed a Skua swoop down, attack and fly
off with the chick.
The Predators Attack
As
soon as the Skua flew off with the chick though, a Giant Petrel started chasing. The Skua eventually dropped the chick in the
middle of an open field. The chick hit
the ground, bounced and rolled a few times and finally came to a stop. Another penguin, a stranger, came out to help
the chick, but two Skuas and a Giant Petrel showed up. In the hierarchy of these predators, the
Giant Petrel is larger and more dominant, so the Skuas backed off, as did the adult
penguin. The Petrel walked over and picked at the chick but didn't attack it,
and eventually, after a confrontation and help from the penguin, the chick
limped off to safe harbor under the protective eye of the penguin. This was the game of predator and prey at
its best!
The
amazing thing was that neither the Petrel nor the Skuas made any attempt at the
end to grab the injured, limping chick.
They just watched him hea d off to the safety of the other penguins. Apparently this was just a game to these
birds! There was no more challenge, and then
they flew off to cruise for more chicks.
Antarctica
Words and
images cannot describe the incredible beauty, immense vastness and remote
desolation of this continent. It is the
coldest, windiest and driest continent in the world. It is the largest desert in the world,
averaging just 4 inches of precipitation a year. Since there is no evaporation,
ice and snow stacks up over years and millenniums, turning Antarctica
into the tallest continent in the world with ice up to 10,000 feet in some
places. It is incredible and magical. As much as we try, it is not possible to
record through images or words what this continent is all about.
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Thanks for visiting. Be sure to explore the outdoors  and enjoy our natural lands. Leave everything as it was when you arrived and it will be a rewarding experience for everyone.
Cliff and Doris Kolber
Kolberphotography.com
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