A Dublin microbiologist spent five weeks looking for microbes on the ice-bound southern continent. Dick Ahlstrom reports.
Dubliner Ronan O'Toole spent five weeks in the Earth's deep freezer in the company of penguins, seals and a handful of humans. The microbiologist went out to Cape Hallet, Antarctica, to study bacteria in the sea ice and came back committed to the preservation of this unique ecosystem.
O'Toole is a lecturer at Victoria University of Wellington in New Zealand and jumped at the chance for a working visit to the real "down under". He travelled from New Zealand late last year during the Antarctic late spring/early summer, when bacterial colonies in the freezing cold sea ice survive temperatures as low as minus 20 degrees and "balmy" air temperatures range between minus 1 and minus 15 degrees.
New Zealand funds research programmes on the continent and operates Scott Base, a place that holds much historical significance for New Zealanders, says O'Toole. The base was built in 1957 under the supervision of Sir Edmund Hillary, the first with Sherpa Tenzing Norgay to conquer Mount Everest. Scott Base is overlooked by Mount Erebus, the site of the Air New Zealand DC-10 crash in 1979 when 257 passengers and crew died while on a sightseeing trip to Antarctica.
O'Toole and colleagues were participating in the Antarctica New Zealand Latitudinal Gradient Project, an ongoing study that uses a latitudinal gradient in the Ross Sea as a means of obtaining a range of climatic conditions across Antarctica. It runs 1,200 km from Cape Hallett to Beardmore Glacier, says O'Toole, with this year's research team heading for Hallett.
He reached the Cape via Scott Base, which in turn is a short distance from the largest research base on the continent, the US-run McMurdo Station on the edge of the Ross Sea ice shelf.
Everything associated with life in Antarctica represents a challenge, says O'Toole. His flight down was on board a USAF C-17 Globemaster, a five-hour journey that can sometimes become 10 if the weather goes bad. If the aircraft takes off and the weather closes in there is no option but to return to the International Antarctic Centre Passenger Terminal in Christchurch to try again next day.
The aircraft landed at McMurdo carrying cargo and 40 people from the American and New Zealand Antarctic programmes, says O'Toole. He remained in the comparative luxury of Scott Base-which includes comfortable beds, showers and even a bar-for some days undergoing "Antarctic Field Training".
This involved getting familiar with the extreme conditions, survival gear and techniques, including how to build an ice shelter. The training was very real, he says. A storm descended on them while there, reducing visibility down from normal to less than 10 metres in a matter of minutes.
His scientific mission was to study bacterial colonies in the sea ice. The organisms tolerate two extremes, cold and high salt concentrations, both there as a result of the continent's relentlessly harsh climate.
Sea brine forms channels in the sea ice which do not freeze but become more concentrated for salt as the temperature drops, O'Toole explains. The microbes live in these channels and he retrieved samples under permit for analysis back in Wellington.
The first bacterium identified was a species of Psychrobacter, an aerobic, salt-tolerant organism that can complete its entire life cycle at temperatures down to minus 10 degrees. In the Antarctic's long winters the brine channels have been shown to remain liquid down to minus 35 degrees. Microbial activity is reduced but respiration and protein synthesis in these organisms have been detected in sea ice down to minus 20 degrees, O'Toole says.
Cape Hallet had none of the luxury offered by Scott Base. There was a mess tent and two large tents set up for the lab work, he says. They stayed in polar tents during the field work. Juvenile penguins proved to be regular guests in the camp, he says. Breeding penguins spend their time in courtship or defending their nests from attacking sukas, but the juveniles had a lot of time on their hands, being free from these chores.
"They roamed around the field camp at night in large gangs like young teenagers," O'Toole relates. Humans are not permitted to approach within 10 metres of a penguin, but this was no impediment to the birds who were very inquisitive.
"They are quite fearless of people and this combined with curiosity means they will inspect any new object or activity nearby," he says. "They used to come out to us when we were working or playing cricket on the sea ice to check out what we were doing."
Some of the juveniles practised their rock-carrying techniques. During courtship rocks are the key to the males' breeding success as male Adelie penguins offer females small rocks to form the walls of the nest.
The trip to Antarctica was a "fantastic experience" and he was grateful for having received a chance to go particularly as participation over five weeks costs €27,400 per person. He was impressed by the researchers and other staff working there who are "dedicated to the cause of preserving Antarctica" and its unique marine and terrestrial ecosystems.