Friday, 14 March 2014

Wildlife update 1: Penguins

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.

Taking a break during gentoo chick counting for a quick lie down. This curious chick, almost fully moulted but with a little down left on the back of the neck and the flips, was curious enough to wander over and try to remove my glasses.

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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