Marine Scientist enthralls audience

Researcher describes Marion Island life among seals, orcas

Marine biologist Tristan Scott enthralled his PROBUS audience when he looked back at his work as a young honours student in 2010 on marine mammal research at Sub-Antarctic Marion Island, about 1,920km southeast of Cape Town. 

“I had just finished up at (then) Pretoria University) and I wasn’t sure what I was going to do next,” he said in his address titled ‘My experience on Marion Island’.   

“I always wanted to do some kind of field work. On a particular day, I arrived at the zoology department on a separate matter when I saw on a noticeboard with various positions on offer.” 

He spotted vacancies for field work on the Marion Island Marine Mammal programme. 

“The only problem was that the deadline was the next day. ‘Oh dear’, I thought at the time, but I went on to the internet and applied. 

Scott’s plans had included opening a metal-rock venue in Johannesburg. “I had a backer and I was very excited about it.” 

But he applied for the research position anyway. 

“I sat up the whole night on the internet and left it there.” 

He received an e-mail saying he’d been longlisted. Not long after that, he was told he’d been short-listed. 

“It’s a big decision to make. I had a fiancée at the time and you’ve got to stay 13 months on the island.” 

The interview was gruelling. Marion Island is isolated and it was a requirement that you could handle the job mentally and physically.  

“I was happy when I heard that I had made the grade,” said Scott. 

The Marion Island Marine Mammal Project he’d signed up for was under the auspices of the South African National Antarctic Programme (Sanap), then a collaboration with the department of environmental affairs and tertiary institutions. 

Scott spent 13 months on the programme, as a field specialist, collecting data on Orca whales, fur seals and elephant seals. 

Uninhabited

The Sub-Antarctic Marion Island is roughly halfway between Cape Town and Antarctica and is one of two islands. 

 “The only people who go there are the overwintering (research) teams. Prince Edward Island, the other island, is completely uninhabited. 

“Our team was a group of 19 and you have to get to know these guys a little bit better before you can spend 13 months on an isolated island with them.” 

They were issued three bags of winter gear and gumboots – the footwear of choice on Marion Island. 

“And you go through about eight pairs in the 13 months!” 

After they’d completed the team training in Cape Town they were issued with more equipment – and then it was time to board the ship, the SA Agulhas One. 

“It was a rickety old rust bucket,” [the upgraded vessel SA Agulhas II has been kitted out with technological advancements] he said. On their five-day journey to Marion island, they encountered some of the worst sea conditions imaginable. 

“You go through the roaring 40s (strong westerly winds that occur in the Southern Hemisphere, generally between the latitudes of 40° and 50° south) and the winds and waves are incredibly hectic.” 

Initially, their home was the old Marion Island base. Built in 1948, it was starting to show signs of wear and tear. However, they were able to move in to a bigger and better building after a few months on the island. 

“This new building [that took 10 years to build] and was officially opened while we were there had everything and we were the first team to move in there. 

“This base as it stands today is absolutely incredible: it’s a hi-tech facility that includes entertainment facilities – even a bar.” 

The SA Agulhas One could not get close enough to the shore due to the weather conditions. With them on the Agulhas were two helicopters and these carried researchers and food provision containers across to the island. 

Weather

Flying the helicopters was also weather dependent. 

“Everything that we need for the entire year comes in these containers. 

Between a new team arriving and the old teams leaving, there is a period called the takeover. 

“On the base are another 80-100 other people: researchers, scientists, and students, all working on other projects. At end of the five weeks everyone leaves and then it’s only the 19 of us (overwintering team) that remains. It’s quite surreal to see them off.” 

Scott was deployed to collect data on seals and whales, with a special focus on the elephant seal. It incorporated the long-term mark-recapture programme, satellite tracking, body mass assessment through photogrammerty and weaner weighing. 

The Marion Island Marine Mammal Programme’s Southern Elephant Seal programme was one of the longest continuous data logging projects worldwide, Scott said. 

“We had to find out how many pups are born to elephant seals on the island every year, and tag every single pup on the island.  

“Sometimes you miss a few though.” 

The mark-recapture programme entails checking southern elephant seals for the presence of tags. 

“Every Saturday you walk around the entire island going to every bit of beach, double-checking every seal colony for tags, studying behaviours and counting how many seals there are.” 

Satellite

 Scott said satellite tracking of the seal population was crucial because these elephant seals spend time on to land for moulting and breeding purposes. “About 70% of their time is spent foraging out at sea …and the rest is spent on land”. 

To put a satellite tracking device on an elephant seal, you first immobilise it and then stick it on to their head with epoxy. 

“When they come to the shore to moult, the top layer of fur will drop off and we can retrieve the satellite tag.” 

He said catching a seal was dangerous but something they often had to do. “We run around them and pick them up by their hind legs …they don’t like being caught… and then we weigh them.” 

Scott said monitoring orcas was the best part of the job. You had to find one of the huts that dot the island and sit it out, moving to the beach as they came past.  

“You wait and wait and when the orcas come past you go out and take information … who the individuals are and who are their family members.”  

Cetaceans spend most of their lives under water and move great distances which makes them difficult to research. Tissue biopsy sampling and satellite tagging allows researchers to gather data.   

Scott described how crossbows that shoot small darts on retrievable lines are used to take biopsy samples from the skin of the whale’s dorsal fin.  

The samples retrieved are used to analyse a range of information about the animals, including their genetics.  

“The University of Tshwane now uses the data for honours and masters projects and PhDs.”  

Gruesome 

Scott said one field work assignment ended up in a scientific journal.  

He spotted an unusual attack by an elephant seal on a penguin during a Marion Island field excursion. 

“One day when I was doing a census, I saw an elephant bull acting strangely towards a penguin,” Scott related.  

 “While mounting the penguin, the elephant bull kept biting the penguin on the neck,” Scott said. 

Eventually the biting resulted in a piece of flesh being torn off.  

“When the bull saw the blood, its behaviour changed: it went from mating with it to eating it. It tore it to pieces. It was kind of strange and horrific and I documented it.” 

He took no fewer than 500 photos of the incident.  

“And when it was finished it decided to come for me and I had to run for my life,” Scott said to laughter.  

  • This article was first published in Talk of the Town, July 18, 2024. The newspaper serving the communities of Ndlambe and the Sunshine Coast, with a weekly wrap of Makhanda news, is available at stores from early on Thursdays.