Our work continues to progress well. We returned from our third outing on Jan. 18 with more samples from two abandoned sites. Our first site was at Cape Ross. Originally, we were to travel to Cape Hickey farther to the north. However, when we went there on the 13th, we saw only rock and snow. The high amount of snowfall this year and the persistence of snow cover has obscured the ground in this area. So, instead of camping there and having little or nothing to do, we elected to get dropped at Cape Ross instead where abandoned penguin colonies were identified several years ago.
The Cape is a large flat peninsula and we were sharing the site with another science group of geologists who are studying the raised marine or beach terraces in the area and how these features relate to sea level change in the past (see figure). Soon after arrival we found several pebble mounds with the typical reddish soils that characterize the old penguin sites. After setting up camp, it was too late to begin work that day. However, the next day we were able to excavate two test pits in two areas that produced small bone samples, eggshell, and feathers. Earlier work here suggests that these sites may date to about 4000 years ago. The lack of bone in the sites may be an indication of their age, if bones deteriorate after that long in the ground.
On our next day we completed excavation at one additional site, then hiked around the area to see if other areas of exposed terrain were accessible by foot. However, there was too much sea ice or glaciers to cross to reach other sites, so we had to forego that option. We did see some nice wind-carved rocks, or ventifacts, out on the tip of the Cape (see figure). The next day our helicopter arrived and we moved our camp to a new site farther south down the coast to Dunlop Island, a large flat island with numerous raised beach terraces.
Again, we established our camp and looked for sites. I was able to find more pebble mounds on top of the highest beach terrace in the middle of the island (see figure), but these appeared to be the only sites here. The next day we were busy and excavated three test pits in three different mounds. Again, the sites produced only small fragments of bone, eggshell, and feathers. However, my impression was that these sites are quite old, perhaps the oldest I’ve found so far. We will have to wait for the radiocarbon dates to know.
Near the island and on the sea ice we saw two Emperor penguins, unfortunately too far away for photos. They were undergoing their annual molt, replacing all their feathers. This process takes several weeks and the penguins just stay in one place, fast, and get the job done. It takes lots of energy to do this, but it’s a necessary process each year to keep the feathers in shape. Otherwise, they would lose their insulative properties and not protect the bird in this harsh environment.
The next day we had to wait for our helicopter all day due to delays at the station. It was nice weather, however, and we had a good view of the area (see figure). Four Adelie penguins arrived and entertained us for awhile. Finally, that night at 9pm, our flight arrived and we returned to the base. Now, we are processing samples again in the lab and will head back out on Monday to Cape Bird where another active penguin colony is located.