"Watchman" field session

I'm just back from a month-long stay in Ratmanoff to carry out the "famous" "watchman" field session.It has been happening every year for almost 15 years and allows us to better understand the king penguins' foraging ecology by deploying GPS and Time-Depth Recorders (TDR). This year, all the animals were also equiped with VHF transmitters to make it easier for us to find the animals back from sea and retrieve their devices thanks to an antenna on the roof of the cabin.
On the way to Ratmanoff, we stopped at Pointe Morne for a "giant petrels and wandering albatrosses check". We had to record the presence or absence of chicks for all giant petrels' marked nests. We also had to check the presence or absence of wandering albatrosses' mates on the nests marked by birders in October and ring them if needed with either a plastic, a metal ring, or both. We then arrived to Ratmanoff for the start of the "watchman" field session. All birders (Thomas, Kéké, Max, Thibaut and I) as well as Micka from the Communication Office participated in the deployment of devices during the first two days. We had to find birds doing their changeovers (when a king penguin goes back from sea, it goes back to its nest, finds its mate, takes the egg or chick back so it can go to sea as well). The mates were marked with coloured paint spray (one colour for the ones that were going back from sea and one for the ones about to leave the colony). As soon as the departing bird decided to go, we had to manage to catch it before it reached the sea and bring it to the cabin, next to the colony, to fit it with a device, weigh, measure and mark it. Some individuals were also only equiped with VHFs (the control group) and their mates were equiped during the next changeover. The "watchman" work could then begin after the deployments in order to not miss the birds coming back from sea. Thibaut was watching the birds in the mornings, and I was doing it during the afternoons. We needed to spot the equiped birds coming back and to catch them before they had made their changeover, which can happen pretty quickly, in order to weigh and measure them again and retrieve their devices. The returns were well-spaced in time with birds coming back every day but one (from one to three birds per day). We missed the stopover of the Marion Dufresne, which came to bring most field assistants of the 61th mission home since we had to stay at the cabin to make sure we didn't miss our equiped birds. This post is the occasion for me to greet the people who left and wish them a good return trip and good luck. We weren't there but our hearts were in it!
The beach of Ratmanoff was as beautiful as usual, with its thousands of penguins and its waves which tops spread in the wind. It's actually one of the biggest king penguin colonies in the French Southern and Antarctic Lands (70000 breeders! it's huge!). We could also see a few rabbits, cats and wandering albatrosses around every now and then. There were few elephant seals compared to the breeding season and a few fur seals were resting on the beach as well. Lastly, we could see a few macaroni penguins, "lost" among the breeding king penguins as well as a rarity of nature - a melanic (black) king penguin a priori reproducing in the colony! When we arrived, some birds had laid or were laying eggs or others had young chicks already or eggs about to hatch. The penguins we equiped were mostly taking care of a small chick or had an egg near hatching; during the field session we saw the chicks grow bigger and become independent. The parents came back to feed their chick by regurgitating the food in their beak. There still were a lot of skuas, waiting around to steal eggs lost by clumsy breeders or chicks that were not guarded well, as well as giant petrels and kelp gulls trying to have a feast as well. This was even more obvious during a rare event; one day, the tide rose "too high" and reached the breeders; it carried away loads of breeders, eggs and chicks causing an important mortality and changing the morphology of the colony in some parts. We witnessed that scene, helpless...
 We also had a few visitors during the field session, which allowed us to have extra hands to carry out another experiment on the energetic cost of walking in king penguins. We fitted birds walking on the beach towards the colony with cardio frequency meters, GPS and accelerometers. Some king penguins, for unknown reasons indeed leave the water far away from the colony and walk towards it instead of swimming all the way to the colony. To understand why we wanted to gain insight into the energetic cost of this extra walk. 
The logistical team spent a few days with us to do some repairs in the cabin. Two colleagues came visit us for a day and other birders came for a few days before the arrival of the "Popchat team" (the team of the field assistant studying feral cats, that were introduced years ago in Kerguelen) (but I'll talk about it some more soon since I'll go to Port-Jeanne-d'Arc to help him out at the end of the month). Well, at the end of the day time flew by until our departure on the 1st of March.


Giant petrel's chick in Pointe Morne


The view we had for a month of the king penguin colony through the « Watchman » window in front of which we spent all our time 


King penguin's chick in Ratmanoff


Spot the odd one out: the melanic king penguin of the Ratmanoff colony

Kerguelen Ratmanoff king penguins chicks petrels foraging

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