When we arrived, it was snowing but the next day dawns calm and sunny. It’s time to hit the water.
Diving the KEP wharf. Elephant seal pups are a trip hazard on the slip. Credit: Claire Goodwin
When we arrived, it was snowing but the next day dawns calm and sunny. It’s time to hit the water. For our first survey dive we are diving on the King Edward Point Wharf which was constructed only a year ago. We seeing what has colonised the wharf, looking for marine invasive species, and checking on the wharf’s condition. But first we must put our many layers of dive gear. The water here is between 1 and 2oC so we need a lot of clothing to keep us warm. I have merino shorts and vest, fleece leggings and long-sleeved shirt, an extra fleece bodywarmer, two pairs of socks, and then my undersuit which is rather like a thick sleeping bag with arms and legs. My drysuit goes over all this – it has seals at the neck and wrists so water can’t get in. I can hardly move when it is all on and look extremely rotund. On my hands I have bright orange dry gloves and a thick neoprene hood covers my head. I waddle with my dive tank off the boat (scrubbing my drysuit boots on the way past) and down to the zodiac to load up. Once kitted up we roll in backwards from the zodiac. The cold water stings my face as I submerge but the rest of me is toasty. The visibility isn’t great, it’s rained recently, and the freshwater has made the water milky. But we can see enough to do our survey. First dive completed we head up the slip, being careful to avoid the elephant seal pups sprawled over it. The pups are making belching and farting noises that my young son would find hilarious.
The following day we are diving from the ship in Cumberland Bay. We load up the RHIB (Rigid hulled inflatable boat) from the second deck level of the Pharos. The RHIB looks rather precarious, it is hanging from the crane, four metres above the water. Cautiously I board and edge my way around to the side furthest from the ship. We grip on tightly as the crane lowers us all into the water with a splash. The crew unclip the shackle and then we are off, racing over to our dive site.
The divers are lowered into the water. Credit: Steve Brown
The RHIB speeding to the dive site. Credit: Juliet Brodie
On this dive I am diving with Karin Gérard, a researcher from the Universidad de Magallanes in Chile. Karin’s research group specialise in looking at how Southern Ocean marine species are distributed and connected, how they have evolved in the past and how they will face climate change. From the DNA of the species collected, they will reconstruct phylogenetic relationships between Antarctic and subantarctic species, and analyse the distribution of their genetic diversity and how populations have changed over time. They are also trying to work out how Antarctic animals might be affected by climate change in the future. The people in Karin’s group work on a wide range of organisms so she has a big hit list of things to collect – everything from starfish to micro-molluscs. We nickname her ‘the dredger’ as she is so fast at collecting, but this is unfair as by sampling on SCUBA she can collect only what she needs.
Karin collecting specimens. Credit: Claire Goodwin
While Karen is searching for her samples, I hunt for sponges. I also photograph and collect other animal species for a reference collection. We hope to create a photographic identification guide to South Georgia’s marine life. To do that we need a photograph of the species living, and a collected specimen to be able to identify in the lab. Then we can match the two and start to recognise more animals and seaweeds underwater. Nobody has photographed many of these species before so there aren’t any existing identification guides we can use. We use nicknames like the ‘dog tongue ascidian’ to let us record them on the site record form until we can get a proper name. This site is a rocky wall so it is good for sponges. When I sample a sponge, first I take a photo. I cut off a small piece of the sponge with a knife. Then, so I can match up the sponge with the photograph, I place each specimen in a numbered plastic bag. This is quite tricky with my thick gloves on!
We spotted this coral on the dive. It is probably a species of Thouarella. I took as specimen so we can identify it. Credit: Claire Goodwin
I also collected a piece of this sponge. It is a Hymedesmia species – maybe one of the new species I described from here ten years ago. But I will need to examine its skeleton to be sure. Credit: Claire Goodwin
The next day I am diving with Paul and Steve as they do a survey transect. They reel 20 metres of measuring tape along the seabed. Then photograph ten quadrats spaced along its length. These will enable us to get quantitative data on the species present. We’ve just finished the transect, 20 minutes into our 30-minute bottom time, when we hear three tings, a pause, then three tings again. That’s Jonathan, our dive supervisor, tapping a metal pipe over the side of the boat, our recall signal. There must be something wrong. We gather up our equipment and head up. We surface near to the boat. ‘Leopard seal! Under the bow!’ Jonathan calls out. Leopard seals can reach up to three metres long and have a rather reptilian head, which gives them an appearance reminiscent of Voldemort in the Harry Potter films. They seem to have no fear of humans and will often approach boats and people. Often their interactions are harmless, but there have been reports of them ripping inflatable boats and in one incident a snorkeller was killed. Since that death, the advice is to avoid diving with leopard seals, hence the recall. We swim over to the boat and try and get out as quickly as possible. But the boat is in thick kelp and my leg is tangled. Eventually I break free and haul myself in. Glad to be out of the water, but a part of me is disappointed not to have seen the seal underwater.
A leopard seal surfaces near the dive boat. Credit: Steve Brown
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