We returned yesterday evening from four days and nights (Saturday – Wednesday) in the field, working out of the NZ Hut at Cape Bird:
Getting there was tricky – the helicopter pilots don’t really like flying there because of the strong winds that come down over the mountains and glaciers, and there was a high chance that we would not be able to get there (or be picked up) at our requested times. But the weather cooperated both ways so that we got in and out just as planned.
So, now for a little refresher in the local Antarctic geography, which is a little confusing for most people, considering that much of the time, the frozen sea ice, ice shelves, and glaciers extend out past the actual landmasses, giving the impression of land. McMurdo Station (along with NZ’s Scott Base) is on Ross Island, which is in McMurdo Sound, in the Ross Sea. The map above shows Ross Island sans ice coverage, but the ice actually extends out from the continent proper, connecting to the eastern side of Ross Island (at a thickness of up to 180 meters) and out into McMurdo Sound, so that the sea in front of McMurdo is perpetually frozen (under normal conditions). You can also see from the map, I drew in the approximate flight path of the helo, which is not supposed to fly over water – and when crossing McMurdo Sound, it is actually flying over sea ice.
Anyways, back to Cape Bird…our helo dropped us off on the lower pad (the winds were too strong to land on the hut’s pad) and we had to lug all our bags and equipment up the hill to the hut. The two Kiwis residing in the hut were Cary and Isaac, and they came down to help us with our baggage. Isaac had been there since mid-November, and Cary since January. Isaac was about my age, and was a university student as well, spending his summer helping out with David Ainley’s Adelie project. It is quite remarkable of him for deciding to spend his summer vacation (all 4 months of it) there, without internet, TV, or phone, and contact to the outside world limited to radio communication with Scott Base, and visitors. Cary had been coming back to Cape Bird for nearly 20 years. In fact, the last time Dr. Emslie was there, 10 years ago, Cary was there as well, and they were happy to see each other again.
The Cape Bird hut was quite comfortable, dubbed the “Ross Sea Resort” by Dr. Emslie. It did indeed have an amazing view, perched on a hill, with the kitchen/dining room wall facing the sea and full of windows.
There were two bunk rooms – one for females, and one for the males, with four beds in each. That meant that there was one extra guy, and so Dr. Emslie happily opted to set up a tent outside.
There was also a “lab” room, which along with lab supplies, housed the big potable water tank. This had to be filled by hand – Cary and Isaac would regularly trek up to collect bucketfuls of snow and ice and bring it back down to fill the tank. Water was definitely the limiting factor for the hut, and water was under strict usage rules – only for drinking (and brushing teeth). Dirty dishes were wiped clean with paper towels, and pots and pans were washed with a minimal amount of hot water + biodegradable dish washing liquid.
There was an outhouse, as well. It basically consisted of two buckets – one for #1, and one for #2. The #1 bucket had to be carried down to the water to be dumped to the sea, and the #2 bucket (also called the “honey bucket”) was packaged and shipped back to NZ for disposal there. Grey water was also dumped into the sea. There was a “shower”, but really it would be more than impractical to use, because all the water that came out of the shower head would have to be collected by hand from the ice/snow, and all the water that came off your body would have to be carried down and dumped into the sea. So I don’t think it was ever used by Cary or Isaac, and the only way to clean yourself was with wet wipes (forget about washing your hair!).
We arrived in Cape Bird around 3 pm on Saturday. After unpacking our bags and setting up our beds, we left for the Northern Colony to look for eggshells and explore a bit. It was sprawling – Adelie penguins as far as you could see, in every direction….40,000 nests – double the amount of breeding penguins + the non-breeders and you get up to around 100,00 individuals.
There were a wide range of chick sizes and ages, as well. But this late in the season, anything smaller than creche-size is going to have a hard time surviving. Like this unfortunate chick, about a week old, and pretty much doomed to die.
These are usually inexperienced breeders who got started much too late – maybe even first time breeders. It’s a tough lesson to learn how crucial timing is in successfully raising a chick and passing on your genes.
Creching is a vital part of the penguin life cycle. Up until this stage they are very vulnerable, especially to predation by skuas, who are relentless in searching the colonies for any unattended chicks. Although once they are creche-size they are too heavy to be carried off, and can even defend themselves quite effectively. The normal breeding season begins when the males (usually first to arrive) reach the breeding grounds. They will begin collecting pebbles for the nest, which is placed in the exact same spot every year! Hopefully, their mate from the year before will arrive a few days later…and then they have to get down to business producing a chick or two,because of the extremely short period of time they have before the harsh weather kicks up again. Usually, two eggs are laid mid-November (into early December). The incubation period is about 35 days, and chicks hatch semi-precocious (born with down and eyes open, but still dependent on parents for food and heat). The chicks then join creche at about three weeks of age. Less than two-thirds of them survive to the creching stage.
I asked Dr. Emslie about creching, because it is an interesting behavior that a lot of colonial seabirds do (best examples being penguins and terns). Once the chicks reach a certain age/size, they gather in little groups that are outside the nesting territories. *This may be partly because the chicks get so big that they simply do not fit anymore on the nest, and are pushing the territorial boundaries and therefore may come under physical attack from neighboring penguins, which is quite unpleasant. Adult aggression appears to be a major factor in inducing creching behavior (Le Bohec 2004)* While the factors inducing chicks to aggregate are poorly understood, there are many obvious advantages to creching. They gather in groups, because there is, after all, safety in numbers…especially from the relentlessly oppurtunistic skuas. The chicks can also huddle together for warmth. Also, this gets the chicks off the nest and now lets both the parents leave to forage for food for themselves and their chick(s). There is also heavy inter-chick competition for space near the center of the creche, where it is safer and warmer. Chicks in poor condition are attacked and pushed out to the periphery of the creche. The chicks on the outside get much less shut-eye because they have to be more vigilant. In a nutshell, creching is a behavior that protects chicks from adult aggression, predation, and harsh weather.
Walking down to the end of the North Colony, you begin to appreciate the enormous Bird Glacier that cuts out into the sea. It was my first glacier up close and personal, and it made quite the impression! It was so beautiful…so massive…and there were little waterfalls of melt water running off its sides onto the ground, and into the sea.
Walking back to the hut, I saw my first skua chick!
Skua parents are very aggressive when it comes to defending their chicks. Just walking around, you are eventually going to get dive-bombed by an angry, screeching skua that thinks you have come too close to their chick – even if you didn’t know there was one around. They relentlessly swoop down on you, trying to kick or scratch you with their feet, until you run away. It’s quite frightening at first. The only thing to do, while moving away from the area, is to face them as they dive down at you and wave your hands over your head. That way you are much less likely to get kicked in the head.
We got back that evening in time for dinner, prepared by Cary. It was canned tuna fish…and we were all so hungry it tasted delicious. We also had some broccoli to add – Isaac and Cary were excited because we had brought some for them with us, as they hadn’t seen or eaten fresh food (especially fruits and veggies) in a while.
The rest of our days out in the field went as followed:
Wake up at around 7:30 am, eat breakfast. Leave the hut by 8 – 8:30 am.
Hike slowly down the beach, stopping at various points (gulleys, McDonald beach, Skua Lake, middle colony) to collect sediment samples and/or eggshells.
Stop for a break and eat lunch around noon.
The farthest we could go was the South Colony, which was a little over 5 miles from the hut. After that, it turned into cliffs.
Start trekking back around 5 pm to the hut, starving, tired, and knees, ankles, and feet aching from the hiking, but happy with lots of pictures and samples and fresh air (and trying to avoid skua attacks).
It was so hard not to stop to take pictures constantly. Too much surrounding beauty!
Hiking back at around 5 pm every day seemed to be the perfect time to see all the Weddell seals hauled out on the beach.
This is something new and exciting I found out from Cary at Cape Bird. Whenever we spotted orca (and we saw three of four pods while there), we were to note down how many, what time, and then….what “type” of orca they were (A,B, or C). Intrigued, I asked Cary what these “types” were, because it was news to me. Supposedly, there is some controversy surrounding the taxonomy of orcas, with some marine biologists currently advocating that orcas be split into as many as three separate species (not subspecies)! The Type A orcas are the typical orca you imagine: mammal eaters (seals and minke whales), larger in body size, smaller pod sizes, medium white eye patch. Type C orcas are the “fish-eaters”: smaller body size, larger pod size, slanted eye patch, off-white/yellowish saddle. Cary didn’t really “believe” in Type B, but there are supposedly intermediate in appearance between A and C, and specialize on seals. Orcas do not normally prey on the Adelie penguins because they are not really worth the effort – they are hard to catch (fast and highly manouverable) and too little meat for the big mammals. Although young orcas will use them as practice chasing, and sometimes throw them around cat and mouse style.
Speaking of which, on my way back from one of the colonies, I found this poor penguin that looked like it had been attacked by a leopard seal, barely escaping with its life:
The skuas very curious about its condition, circling like vultures and trying to see if they could finish the penguin off.
Isaac said that they had seen similar injuries before and that the hardy little birds survived.