Penguin paleohistory at Casey
How long have Adélie penguins been breeding in the Windmill Islands region? Has the population been larger in the past than it is today? Has penguin diet shifted with climate change over the past few thousand years?
These are just some of the questions now being addressed in a study of abandoned penguin colonies now underway at Casey station by Dr. Steve Emslie (University of North Carolina at Wilmington) and Dr. Eric Woehler (AAD).
By locating and excavating into these abandoned sites, characterized by small to large pebble mounds today, it is possible to recover well-preserved remains of penguins (including bones and eggshell fragments) as well as organic remains of some of their prey (fish bones, otoliths, and squid beaks). Radiocarbon dates of these remains will provide an occupation history for Adélie penguins in this region and insight into how populations have cycled over millennia, especially in relation to climate change.
In addition, the research will provide minimal ages for glacial retreat in the Casey station area, an event that had to occur before the penguins could establish colonies on the ice-free terrain surrounding the station today.