As we have recently highlighted, plans in Antarctica often change due to the vagaries of the weather. Last week, after taking samples and treating experimental plots near Lake Bonney and South Side Lake Hoare, we were supposed to spend just one night in Lake Hoare camp – the main field camp in the Dry Valleys and one of our favourite places. But the next day all helicopter flights were cancelled due to poor weather, so we had to postpone our trip to sample an experiment and stay at the camp for at least another night. This gave us the chance to go on a hike to one of the most scenic places in the Dry Valleys. Along the way we encountered some remarkable signs of life – and death.
- A mummified seal on the lakeshore
Every now and then, seals and penguins stray from the vicinity of the ice shelf into the Dry Valleys. It usually doesn’t end well for them. There are many seal remains in the valleys, some well preserved due to the cold and dry conditions. Some are centuries old; some may be as old as the human-made mummies from ancient Egypt. One dead seal we saw close to our path during the hike, however, struck us as special for an altogether different reason: on the lake sediment behind its tail, we saw a trail of green and red. The decay of the unfortunate seal fertilized the sediment around it, allowing living algae and cyanobacteria to flourish and become visible to the naked eye. The fuel of this freshwater hotspot (the seal’s remains) came from the ocean, an example of what we ecologists call a resource subsidy.
- A dead penguin and a hungry skua
Near the Seuss Glacier, we saw another unfortunate marine animal – a rather fresh dead penguin lying on the shore. To our surprise, on our way back we found it a few meters away from its original position. A few scattered feathers all around, different from those of the penguin, gave away the culprit: a young skua which we had seen flying over our heads not long before. Skuas are large predatory seagulls with a particular taste for penguin entrails, but this seasoned penguin proved unpalatable even for the skua. The young bird will not find anything to its liking in Taylor Valley – unless scientists drop their guard long enough for the skua to steal their snacks, as sometimes happens at McMurdo base.
- The thousand-year old lichen
Not far from the seal we found one of the largest lichens we have seen out there, at over 10 cm across. Since lichens in Taylor Valley have been found to grow less than one millimeter per century, this one must have started its growth at least one thousand years ago. This makes it older than most living organisms you will ever see, including some of the biggest trees.
It took us a couple of hours to get from Lake Hoare camp to the Seuss Glacier, one of several alpine glaciers in Taylor Valley. Courtesy of the cloudy sky, we could admire its jagged, rugged shapes without being dazzled by the albedo. But as impressive as its stalactites and column of ice were, the glacier was not our real destination today.
After a rather demanding trek over loose, sandy surface on a steep hillside, we reached our destination. In an expanse of sand incessantly swept by cold wind, overlooking the frozen cascade of the Seuss Glacier coming down from the mountain, we saw boulders standing out against the bleak sky. Instead of the curved or angular boulders typical of glacial landscapes, these come in shapes that would befit a sci-fi movie. This martian landscape is near Andrew’s Ridge in Taylor Valley and is a great place to see ventifacts, rocks wrought into peculiar shapes by the abrasive action of the wind-transported sand.
It took us almost four hours of walk to reach this place, and almost three hours to get back. On our return to Lake Hoare camp, after enjoying a wonderful meal prepared by camp manager Rae Spain and Renee Noffke, we were understandably tired, and eager to crawl into our sleeping bags! The next day there will be work to be done.
Written by: Walter Andriuzzi