This week at Davis: 20 December 2019
Dr Louise Emmerson's fond reflections on her past two months of work on the seabird science program at Davis.
Seabird studies in Prydz Bay
We have had a very productive field season travelling across and above the sea-ice to reach penguins and petrel breeding colonies. Often we know we are close to the penguins because the distinct waft of krill and fish reaches our nostrils before we can see the birds, and as the snow has melted forming muddy patches around the colonies, that distinct smell lingers in our shoes and clothing. As we get closer, we can hear their indignant calls when one strays too close to another nest and then tries to run past. I laugh as I watch them give each other a peck on the way past, not a hard one, just a gentle reminder to not even bother trying to steal any rocks or else. More than once this summer, we have also heard the more intense flapping of flippers as they pulverise each other for stepping out of line. A penguin colony is often bustling with unexpected noise.
Part of our goal is to understand more about the birds response to the environmental gradient that extends down into Prydz Bay, home to a very large Adélie penguin population (at least a million breeding pairs) and with large populations of flying seabirds. So we set about downloading memory cards and installing remote operating cameras to capture the birds lives.
We also deployed satellite trackers on Adélie penguins to see where they forage. The tracker data and our on-ground observations of the direction the birds wander across the sea-ice to get to their foraging grounds is a good reminder that even the best ecological theory for optimising behaviour for energy efficiency is thrown out the window when it comes to penguins. We are left wondering what goes through their minds and indeed why are they walking parallel to the ice edge to get to their foraging grounds instead of choosing the shortest route!
This year we counted cape petrels and set up cameras to monitor their breeding behaviour. Capeys, as we fondly call them, are a sleek brown and white bird which is very hard to see on the guano smeared rock slopes that they breed on. Their colonies are filled with a constant incessant chatter with high pitched screeches that makes you think of laughing chickens. They have breeding populations on the islands near Davis Station and deeper within Prydz Bay. We are using our count and camera data to assess whether their population size has changed over the last decades.
On one of our far-flung trips south of the station to count cape petrels, we had a visit from a group of emperor penguins. First, they came and surrounded our quad bikes and checked them out thoroughly. Then, they surrounded and inspected us with the same care. As they approached, we knelt down to get to their height and to not scare them. They weren’t scared of us. They happily stood close by and sang to us for some time. Such moments reminds us what a privilege it is to be in their territory and to have a visit from the penguins.
It is always refreshing to see first-timers to Antarctica view the place with a sense of awe and to hear of their first penguin encounter. I am left smiling that penguins have a universal capacity to enthral all those who spend time with them. Even the most hardened tradies who forgot to even put seeing a penguin as a high priority on their list of things to do in Antarctica (I know, unbelievable) are transformed into people that will probably spend every opportunity on station wearing a penguin onesie.
Thanks to all on station and back at Kingston who helped make the field season such a good one.