A young woman sits on the beach and admires the mountains, the sea and sky lit by the midnight sun of Arctic nights. Who is she and what is she waiting for?
You might think that this is a scene taken right out of a Hollywood movie, but this is happening in real life, and the woman on the beach is Charmain Hamilton, a scientist at the Norwegian Polar Institute. She is waiting for ringed seals to appear, and with their help she can study the reduction in sea ice and the effects of climate change.
Text and photo: Maria Amelie
Charmain Hamilton was always interested in biology but got interested in Arctic biology by chance. When she was doing a bachelor's degree in Canada she got an opportunity to study abroad for six months. In her third year she left for Svalbard, and little did she know that this would open so many new doors in her life.
"Already three weeks into my studies on Svalbard, I emailed my university in Canada and asked if I could stay here for a whole year instead," says Charmain and smiles. That led to a master's degree in Tromsų, and today she is finishing her PhD in the same city.
What were you first impressions when you came to Svalbard?
- When I arrived I was surprised by how big the community was and the amount of life compared to Arctic Canada which is more desolate at that latitude. The West Spitsbergen Current (WSC), which is a branch of the Gulf Stream, flows past Svalbard, making it much more habitable compared to similar latitudes in Canada.
She also fell in love with the views, mountains, and fjords and being so close to the ocean.
Why arctic biology and arctic animals?
- What really interests me is the extreme conditions that the animals and the plants experience and the adaptations and life history traits that they have in order to live and thrive in these extreme conditions. I'm also interested in how they are responding to the present climate change. I find arctic animals to be very interesting, charismatic and fieldwork with them is great fun, especially when it comes to ringed seals.
Could you tell us a little bit about your research project?
- In 2006, there was a sudden and dramatic shift in the sea ice conditions around Svalbard. This led to several things, for example a decrease in the amount of solid ice that forms in the Svalbard fjords and the summer position of the Arctic ice cap moving much further north.
According to some of the projections, the Arctic may be seasonally sea-ice free in the summer by as early as the 2030s. I'm studying how reductions in the extent of the sea ice are influencing three ice-associated arctic animals - the ringed seal, polar bear and ivory gull.
Why those three?
- These species are connected and are extremely dependent on sea ice for various aspects of their life cycles - ringed seals give birth, nurse their pups and rest on sea ice and also forage on ice-associated prey. Ringed seals are the primary food source for polar bears throughout most of their range. Polar bears use sea ice as both a hunting and a travel platform, and ivory gulls scavenge at polar bear kill sites.
What is your fieldwork like? How do you plan?
- At this stage of my career, my supervisors do the planning and I join them. Over the course of several weeks we capture ringed seals and attach biotelemetry tags to them. These tags will stay on for a maximum of one year before they fall off when the seals moult (i.e. replace their hair).
What does it mean for your field that you can use that kind of technology?
- The study of animal movement and dive behaviour has been revolutionized by biotelemetry. For example, elephant seals can dive to a depth of over one kilometre and be under the surface for over one hour."
She adds that tags have become much smaller now and are able to measure more parameters due to technological progress. It is possible to put them on smaller animals than before.
After the tags are on the ringed seals, they are released back in the water. Over the next year the ringed seals send information back to us about where they are and what they are doing (i.e. how deep they are diving, how long they are diving for, how long they are resting, etc.).
How do you catch them?
- We go on an expedition on a sailboat to different locations around Svalbard, we sit on the shore, put out a net and wait. Ringed seals often swim along the coast, near glacier fronts where they feed. They are really curious, so just sitting and talking on the beach is sometimes enough to attract them. They will wonder what is happening, swim over to us and hopefully become entangled in the net. Once they get in the net, we immediately take them out of the water and transfer them into a smaller, individual restraint net on shore.
Do you have to drug them?
- No, not with ringed seals. They aren't aggressive towards people, and I have been very close to them without the seal trying to bite me.
One time we had a really big ringed seal, and it didn't want to move back towards the water after we had finished tagging it. So first three strong men had to carry it to the sea shore and put it down a few cm from the sea, but the seal was still not going anywhere, just lying there and relaxing. So they had to just pick it up again and put it in the water and only then did the seal swim away, says Charmain and laughs.
And what about polar bears?
- I have never experienced polar bears close to us during expeditions. But of course when we are on the beach we have to constantly look out for polar bears. We have flare guns to scare them away in case they come too close and we can also quickly get into the zodiac boat and leave the beach. If there is a real danger and we have to defend ourselves, we always have a rifle with us.
- A lot of the research is done on the computer in my office. So it is by no means just field work. Photo: Maria Amelie
- So after you put tags on seals, you must gather a lot of data. What do you do with it?
- Oh, yes. Most of the year I sit at my computer and do various statistical analyses with huge amounts of data in order to figure out the animals' movement patterns, how long and how deep they are diving, how much time they spend at the surface between dives, how long they are resting and what is responsible for any changes in these parameters.
Using this data, we can hopefully begin to understand what the seals are doing and how they are responding to present environmental conditions. We are really interested in how these responses and behaviours can vary over time in response to factors such as climate change.
Charmain has now started to compare data from both polar bears and ringed seals from before and after the big climate shift in 2006. She wants to understand how the ringed seals and polar bears and the predator-prey interaction between them are affected by the decrease of the sea ice.
- Ringed seals have two different movement strategies. They either stay near the glacier fronts at the coast of Svalbard, or they move offshore during the summer and autumn to the southern edge of the polar ice cap, especially juvenile seals.
She found out for example that offshore ringed seals are moving greater distances per day, are diving for longer periods, spend less time at the surface between dives and are resting less than before 2006. This means that the amount of energy they are spending to find food has increased.
Not surprisingly, polar bears in Svalbard also have the same two movement strategies.
- I am working on analysing the spatial overlap between these two species for both movement strategies. The earlier melting of the sea-ice in the fjords means that it is much harder for polar bears to hunt ringed seals in these areas.
What are the consequences of all that?
- The consequences are that if ringed seals are not finding enough food to compensate for their increased energy expenditure, then they don't accumulate enough blubber stores for the winter, which could impact their growth, reproduction and ultimately their survival.
The primary hunting strategies for polar bears are stalking a seal on sea ice and waiting at a breathing hole for a ringed seal to surface - both of these hunting strategies require large expanses of fast ice in the fjords. The earlier melting of the fast ice or the failure of the fast ice to form at all has made it more difficult for polar bears to hunt ringed seals.
After the change in the sea-ice regime, polar bears are now spending more time close to the nesting places of ground-nesting birds, like geese and duck. They have been observed eating eggs and their impact can be very high. Polar bears can eat around 90 percent of the eggs in a colony, as the adult ducks and geese have no defence strategies against polar bears. So polar bear predation at bird colonies can have quite a catastrophic impact locally.
What impact has less sea-ice on animals in the Svalbard area? That is one of the questions I would like to find the answer to. Photo: Maria Amelie
What drives you to study this?
- I think that it is really interesting to study these species and to be one of the first ones to discover and explain how less sea-ice is impacting these animals in the Svalbard area. We learn a lot every day about how they are tackling the new challenges and about the area that is affected by climate change.
Svalbard is also warming faster than other Arctic regions, so it is likely to serve as the "canary in the coal mine", with the effects that we are observing presently in Svalbard expected to spread to other Arctic areas in the coming decades.
Advice to those who want to become a researcher in this field?
Be interested and show that you really want to work. Take the opportunities that are presented to you.
I think it is a good idea to study abroad. You experience and learn new things and also meet people that you likely never would have met otherwise.
Learn statistics. When I started my bachelor's degree, I never thought that I would spend so much of my time doing statistics. Being a biologist is not just lab work - statistics is important in many biological fields, including in the field of biotelemetry.