Update #7
3 Feb. 2005
Before we left the Italian Station, we were able to complete two more days of field work, another trip to Cape Adare and a trip to Cape Hickey and Prior Island. Both these trips were interesting and exciting, giving us some of the best data of the entire season.
The second trip to Cape Adare was similar to the first in terms of flight time, questionable weather conditions, etc. However, once again we lucked out and were able to see the beach with the penguins and make it through the clouds and fog for a landing. This time, however, I wanted to stop on top of the Cape first, where the penguins have been climbing up for nearly 300 m to reach their nesting spots. We landed well away from these upper colonies and began hiking on the downward sloping terrain towards the edge of the cliffs overlooking the main colony on the beach. On the way, I noticed lots of large natural mounds, but the tops of them looked like they had been used by penguins for nesting sites in the past. Sure enough, closer inspection revealed up to 40 cm of penguin sediments, bones, feathers, and eggshell fragments on many of these mounds. In the little bit of time we had, we counted dozens of these mounds scattered over this area. So, obviously there were once thousands of penguins breeding up here, a long walk from the beach! I was able to collect small samples from three of them before we started to head back down to the beach.
Just as we were about to leave the top, however, I noticed a small cross on a boulder not far from one of my sites. I then remembered that there was a grave up here of a person who died during the 1899 Borchgrevink expedition. A group of 10 men and 75 dogs was dropped off at Cape Adare that year to spend the winter. Their hut, which I mentioned in my last update, is on the beach. The man buried in this grave was the expedition zoologist who died from unknown causes at 28 yrs old. His pick is still on his grave, as well as a mosaic of white stones placed in the shape of a cross, as they had been left over4 100 yrs ago, perfectly preserved.
Next we flew down to the beach and landed near the huts again. I took photos of a dog bone, a humerus, we found last time that has cut marks on it from being butchered for food. Apparently, this was one of the 75 dogs brought by Borchgrevink and they must have eaten some of these dogs during their winter stay, a not uncommon thing in the Antarctic in those days. We then walked farther into the main colony than last time to collect more samples. Near the back, towards the cliff, I found one penguin mound that was bisected by water, exposing a cross-sectional profile of the mound. It was perfect for sampling as I could see the bottom sediments, just above natural beach sediments, that marks the first occupation by penguins of this area. I hope to have enough organic remains in my sample to get a radiocarbon date for when this first occupation occurred.
Working back to the cliff, I spotted a large moraine with an exposed mound on top. It looked thick with penguin sediments so we worked our way up to it. As I hoped, it was over 2 m thick and had penguin remains and pebbles all the way down. Since it was at a higher elevation as well, at 24 m above sea level, it could represent an even older occupation than the beach mounds where rising sea levels would easily flood these out. Just as I started to sample here, the pilot (this time Steve) called and said we should leave soon--clouds were coming in again. I quickly bagged two samples in the middle and bottom of this profile, then we all ran back to the helicopter. We took off in a snowstorm and fog, but with enough visibility to get off the beach. We flew along the shoreline towards the base of the cape, but soon found our return path blocked by thick clouds. Without blinking an eye, our pilot turned around, went back to the tip of the cape, and crossed over to the opposite shoreline on the seaward side. We followed this and found a path through to Cape Hallett, a narrow escape from having to spend the night out waiting for weather to clear. Steve was glad we had run back to the helicopter as 10 more minutes might have meant a night out, plus he didn't want to miss steak and fries night at the Italian station!
After that long day in the field, we processed those samples, then flew south to Cape Hickey for the day. This day was much nicer--calm and sunny. I had wanted to return to Cape Hickey, a small point that is mostly covered by glacier with only a relatively small exposed area of rocky terrain, since our first visit here last year. The sites we sampled then included one with dates from 27,000 - 38,000 years old, the oldest dates on Adelie Penguin remains now known in Antarctica (or anywhere, for that matter). I wanted to look at the deposition of these sites again and collect additional samples that would help verify this age. So, we landed on the exposed ridges on this cape and began looking at the sites. We relocated the old site from the previous year and took one more sample here. Then, I found another small deposit above it that I also sampled. On two other ridges to the west we found two more sites to sample, so we have plenty now from this area. It will be interesting to see if we continue to get the old dates.
At noon, we flew over to Prior Island, only a few miles to the north of Cape Hickey. Again, I had sampled one site here last year that dated to 3500 yrs old, but I wanted to survey for more. We found many more sites on the east side of the island and sampled one of these. Again, it will be good to see how this will conform to our dates on the other site we did here last year. By 4 pm, we finished our work and returned to the station. Another good long day in the field.
After completing all our lab processing, we gave our thanks and said our goodbyes to everyone at Terra Nova. We hated to leave such a nice friendly station, but it was time to go. We flew back to McMurdo by twin otter on Monday, Jan. 31. We have only a few days here, but I wanted to still try for one more day in the field. I requested a flight on the Coast Guard helicopter to Franklin Island, north of Beaufort Island, where there is an active penguin colony. We got out there on 2 Feb. and landed on the top of the island. High cliffs and steep slopes at least 200 m high surround this top, with a large flat beach below that has the penguins on it. A few small groups of penguins, as at Cape Adare, had found ways to climb higher near to the top to locate their nests in small colonies there. We did not find any old colonies on top, and it looked too difficult for us to attempt a climb down to the beach, so we stayed for only an hour and then flew back to the station. At least we know what is on the island for any future trips out there.
We are cleaning up the lab and packing our things today. Tomorrow we will fly by C-141 to Christchurch, then spend about a week in New Zealand before heading back the the states and Wilmington. It's been a good season. The bad weather caused problems, but the trips to Cape Adare and Cape Hickey made up for everything. We will have lots of good data to analyze that will answer more questions on the occupation history of penguins in the Ross Sea over the past 10,000 years and more.
See you next year!