Here on the Isle of May the grey seal breeding colony is getting crowded as we approach peak pupping time, which is usually in early November. As the colony fills up with adults and pups, there are more disagreements between neighbours or seals trying to move through the colony, travelling either to their pup or back to sea. So far this year it has been a dry season for the seals, we’ve not had much rain and the pools that are usually scattered throughout the colony have dried up. This unfortunately means that there is much more movement of females around the colony than usual as they try to commute to water sources and then back to their pups. Grey seals typically need access to pools of water, or the sea, regularly to help them cool down. The thick layer of blubber that keeps the seals warm when swimming in the cold north sea for days at a time means they can overheat when constantly out on dry land. In seasons when the weather is dry and pools are scarce, grey seals mothers spend much more time moving about seeking water and less time close to their pups, feeding and protecting them. For the seal’s sakes, I hope that we get a bit of rain soon even if it makes our fieldwork more unpleasent!
For the PHATS team, our project work within the field season is officially starting today. One of the study mothers has now produced a large fat pup who is only one day away from weaning, so last night it was time for research assistant Holly, team leader Dr Kimberley Bennett and myself to get our tissue culture lab ready for the arrival of our first sample. When a blubber sample is taken from a seal for our work we use it in as many ways as possible to get the most information out of the tissue. We run some of the blubber to detect persistent organic pollutants (POPs) contamination in the pup, which is what I was doing over the summer in Belgium with our samples from 2015 (read about that here). The rest of the blubber will be kept warm and well fed with media solutions containing sugars, salts, proteins and fatty acids so that the cells within the tissue stay alive. We can then expose these blubber cells to different experimental treatments of POPs (like polychlorinated biphenyls, PCBs) or hormones that are meant to regulate fat tissue function to explore how hormones control fat mobilisation and how POPs interfere with this process. Tissue culture works involves a lot of lab equpiment that is tricky to ship out to remote research sites, but we have managed to find a small CO2 incubator and UV hood which we can transport out by boat to the island. With a lot of ethanol and lab diligence, we can create sterile conditions for culturing cells out here for the PHATS project, and we’ll spend the next 6 weeks keeping the tissue culture lab running here.
Around the island all the other scietific research projects on both the seals and the birds continue as the season progresses. There are many other projects that are happening at the same time as ours on both the seals and the birds here on the island. Over the last week, Callan Duck from the Sea Mammal Research Unit has conducted an aerial survey of the entire Isle of May colony by plane to perform the annual count of grey seals on the island. Callan will fly over grey seal haul outs all across Scotland throughout the breeding season to monitor the size of seal populations around the country. The bird researchers from the Centre for Ecology and Hydrology are also doing the last mist netting and trapping to catch and ring birds on the island before their research station at the Low Light closes for the winter. They have been kind enough to show us many of the interesting birds they have ringed over the last week, inlcuding waxwings, fieldfares and a long eared owl!
MEANWHILE We’ve had two birthdays in the last week so the PHATS team has been baking! I’ve made birthday cake, Holly helped make 60 profiteroles by hand and Kimberley made an epic beef and ale pie for dinner last night. The team leader here on the island also treats us to pancakes every sunday, so we had a lovely morning yesterday enjoying the biggest stack of pancakes I have ever seen.