Gentoo Penguin
Having started
to hatch just before I left, it was pleasing to return to see good
numbers of large Gentoo chicks covered in dense down. This has been
shed as their adult feathers poked through and by mid-February most
of them had explored the edge of the sea. This tended to take the
form of wading into the sea to about waist depth, falling forward and
flapping wildly on the surface. They'd try a few dives but at first
most are carrying too much body fat so just flail on the surface.
That doesn't last long before they turn and run back onto the beach
where their less adventurous pals stare at them like they're
expecting tales of the wide ocean. With time the fat is replaced with
muscle, helped by vigorous flapping on the beaches, and they start to
venture a further and further into the water, diving and chasing each
other around.
Throughout all
of this they are still being fed by their poor parents. The adult
exits the water and walks up the beach calling. It doesn't take long
before one or two chicks, frequently the same size as the parent and
often fatter, come charging toward it. The adult turns and runs,
often heading right down to the waters edge before allowing its young
some food, hopefully a belly-full of regurgitated krill. The running
away from the chicks draws them closer to the water, maybe an
encouragement that they should be out feeding themselves. It also
ensures the fitter, healthier chick, the one that can keep up, gets
fed first; an important strategy to maximise the chances of success
in a lean season.
Young penguins enjoying the wave pool - one of the more sheltered bays - before they head for the open sea, |
My work with the
Gentoos has mainly been to count the number of chicks in all the
colonies. With approximately 4,000 on the island they have had a
reasonable year. Chick health is roughly worked out by weighing them
(not all 4,000). By comparing numbers and weights to those collected
every year for the last few decades we can look at long-term trends
in these species that are key indicators of the health of the whole
Southern Oceans.
An adult being harasses for food by its two strapping chicks, |
There is
another, even more glamorous part to my job with the Gentoos. A few
evenings after dinner I donned latex gloves, took some bags and a
spoon and headed over to Landing Beach. There I positioned myself
near the colony, with a good view over many adults.
I wait with
baited breath for this one moment.
Over to the
left! It happens! A penguin does a poo!
Brandishing my
spoon I hurry over before the Sheathbills can get to it and scoop up
as much of the poo as I can, putting it in a little bag which I seal
and put in a larger bag.
Back in the lab
I will label and freeze this before returning it to Cambridge.
Me barely able to contain my excitement at a particularly good bit of gentoo poo. (Hannah's photo). |
Rather than some
weird, long-range-mail based campaign of abuse, this is part of an
experiment to try and determine Gentoo diet through isotope analysis.
Macaroni Penguins
Like the Gentoos
the Mac chicks have also gone from small balls of fluff to fat balls
of fluff to sleek swimming machines. Where the young Gentoos get to
splash about a bit in the shallows that's not really an option for
the Macs as, with big waves breaking against the steep rocks, getting
in and out is an art form that the adults often fail, getting washed
down the big beds of kelp.
A creche of fluffy young penguins with a few adults on guard around them. |
A fairly young Mac (note the short eyebrows) wearing a sort of body warmer made out of its old, unmoulted feathers. |
Counting and
weighing the chicks is again the priority in terms of monitoring but
there's several non long-term projects that I've been getting up to.
One recent one is observing behaviour during moulting, which is nice
as I just sit and watch the colony for a while, recording how often
the birds preen themselves and how often they preen their partner.
A whole load of jumping Macs heading back for the colony. |
"You've got to fly like an eagle... leap like a salmon... etc..." |
The scramble to get out when a good wave gives you a leg-up. |
The one that mis-times it ends up frantically paddling upstream while moving down. |
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