Friday, 22 April 2016

South American update

Dear PenguinPromises

The penguins are now back home in the nest after a lovely long rest out at
sea.
After two months of feeding the chicks around the clock, the adults were
exhausted and under-weight. So for the last few weeks Promises and the other
adults have been out at sea eating as much food as they can catch to recover
the weight they lost.

Now that they are fully rested and fattened up, the penguins have returned
back home to the nest where Promises will remain for the next month or so.
Really Promises would prefer to be heading off to Brazil for the winter
migration, but first the penguins have to change their feathers, and they
have to remain out of the water for three to four weeks in order to do that.

All penguins change their feathers once a year. The feathers are very
important.
They keep the cold seawater away from their skin so that the penguins do not
freeze to death in the cold seawater. But to work properly the feathers have
to be in good condition, and during the year the feathers gradually get
damaged and eventually need to be replaced.

Juveniles and adults that have not reared chicks change their feathers in
January, and leave the colony for their winter migration during February or
March. Adults that have successfully reared chicks, such as Promises, are
considerably delayed in changing their feathers because they first have to
finish rearing the chicks.
They then have to spend time recovering their weight in preparation for a
long period without food.

Recovering weight first is very important, because the weight that they gain
and loose is body fat, which is the penguins' energy store. People and
domestic animals, such as dogs and cats, are virtually unique in gaining
weight unnecessarily.
In the wild gaining weight is an important aid to survival. Animals gain
weight when there is a surplus of food, so as to provide a reserve of energy
for times when food is difficult to find. This is especially important for
penguins that go through periods without food each year as part of their
natural cycle.

The change of feathers takes about three weeks in all. During that time
Promises cannot go into the water at all, so the penguins have to go without
food for at least three weeks.

It is not just a case of three weeks without food. The penguins also have to
use up valuable reserves of protein, energy and minerals in order to
synthesise the new set of feathers. If the penguins were not well fed prior
to beginning the process, they would be at risk of starvation before the new
feathers had finished growing.

Thankfully that rarely happens. Penguins instinctively know to build up
their body weight prior to changing the feathers, and penguins are used to
going through natural cycles of increasing and loosing weight. It is all
part of the life of a penguin.

The new feathers begin growing underneath the old feathers, and push the old
feathers out, rather like our teeth do. The old feathers fall out, leaving
the penguins looking like worn out soft toys (see the attached photo).

In the photo you can see how the old feathers fall out, and the new feathers
grow underneath where the old feathers have been lost. The new feathers are
not yet fully formed, so they are still short and fluffy, but when they are
fully grown the new coat is sleek and shiny.

The old feathers usually fall out around the chest and tummy to begin with
because that is where the penguins can reach easily with their beaks to
preen. Preening means grooming the feathers, and it helps the old feathers
to fall out and helps to reduce the itching. It also helps to align the new
feathers so that they lock together to form a tight waterproof layer.

The penguins have a gland near to the tail that produces a waterproof wax,
and during the preening the penguins spread this wax through the feathers to
make the feathers waterproof. That is why the fully grown penguin feathers
look shiny, and why water runs off the penguin instead of soaking into the
feathers.

The penguin behind the bush in the photo has lost virtually all the old
feathers, except for the top of his head and around the neck. These are the
areas where the penguins cannot reach with their beaks to preen, and so they
are the last areas to loose the old feathers.

When the new feathers have finished growing, Promises will set off on the
winter migration up the coast of Patagonia towards Brazil. I will write to
you again when the penguins leave.

Our work to protect penguins in the Falkland Islands is featured in a new
film that premieres on 14th April. Until the release I only have a link to
the Spanish trailer
https://www.youtube.com/watch?v=_lV3UjYWV78

Later this year the film will be shown to a wider audience on public and
cable television, and it should then be possible to view the complete film
on YouTube.
I will let you know when I have news about that. Other documentaries about
our work by Paramount Pictures "Wild Things" (2000), BBC TV "Explore" (2009)
and Mare TV "Feuerland" (2005 in German) are shown at the bottom of our web
page www.seabirds.org

Thanks to all our supporters for making this work possible

Best wishes from Mike

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