I was lucky enough to get a tour by the “Birders”, a group of scientists who have been studying the Adelie Penguins, Giant Petrels (“Geeps”) and Skuas of the Palmer Station surrounds since the 1970’s. They have seen a sea of change.
Litchfield Island, now an Antarctic Specially Protected Area for its diversity of moss and lichen, was once home to a colony of several thousand Adelie penguins. In more recent years the island has had increased snowfall, and even rain. It rained while we were at Palmer… I know right, rain in Antarctica?! It is actually becoming a common occurrence in the Western Antarctic Peninsula.
Adelie’s love ice, are ice dependent actually because of their food-krill, so you must be thinking how can snow hurt them? Well the snow falls all over them and their nests. Their body heat is enough to melt the snow around its nest. This can result in pools of water that drown the eggs. To make it worse, if it rains after a snow, the entire colony can get flooded, killing all the eggs for that year. When this keeps happening, the colony eventually goes extinct.
Now on to Torgerson Island
Torgerson is the closest Island to Palmer Station. It is home to an Adelie penguin colony that is can be visited by tourists and station personnel, so basically anyone. The island has been split into an “Open” and “Closed” (or Restricted) zones. The closed zone is a sort of control for scientist working on questions about the impact of tourism. Only they can enter the closed zone.
You might think that splitting the island in half would make it easy to study the impacts of tourism. The above photo was taken in the tourism zone, if you squint you can see one penguin. However, you must remember that this half of the island happens to get a heck of a lot more snow that the closed half (due to its terrain and orientation). Snow is therefore partially responsible for the differences in penguin numbers.
How different are the penguin numbers between the sides? Let me show you. The first photo is from the boat landing area at the boundary of the zones and shows the restricted zone. The second is from the same location and shows the open zone.
Now as you may have guessed, colony size plays a huge role in how vulnerable to climate, disturbance, predation etc the colony is. The smaller colonies are more likely to loose eggs/chicks to skua predation and are more likely to loose an entire years eggs/chicks in a flood. The colonies are the “open side” were on average smaller to start with, and are significantly smaller now. When the Birders are able to tease apart the impacts of weather, colony size, and tourism they will have one heck of an amazing paper.
We had a few “guests” at Torgerson Island…..
Now onto Humboldt Island.
This island, of course, has Adelie penguins, and I will get to them later. What we came to see are some very special “Geeps” (Giant Petrels). Giant Petrels are typically very scared of humans. Most birds will fly away before a good, trained and careful researcher has an opportunity to get their data. So the Birders started a habituation program. Patiently and slowly (more than 10 years and running!) they got the Geeps on the island used to human presence. Over the years the scientists were able to get closer and closer without disturbing the birds. Now the Birders can walk right up to the Humboldt Island Geeps and attach a satellite tag while the bird is completely relaxed… don’t believe me?
Now for the visit with the penguins. We were fortunate enough to get some demonstrations about proper egg and chick care.
Penguins must be very careful parents so that there eggs aren’t stolen by hungry skuas.
So in summary, Adelie penguins near Palmer Station are cute, trying to be good parents and protect the young from predation, but are struggling with the effects of warming (snow and rain) and possibly tourism impacts.
Here is your parting penguin…