Seattle Aquarium mammal biologist, Julie Carpenter recently assisted NOAA scientists from the Alaska Fisheries Science Center with their annual research in the Pribliof Islands of Alaska, which are home to breeding colonies (or rookeries) of the northern fur seal. By collaborating on the research and actually participating in it side-by-side with the field researchers, Julie gained firsthand experience and knowledge of the research techniques and the technical challenges of working with the wild population, making her uniquely suited to bring a deeper understanding of this work back to the staff and visitors of the Seattle Aquarium. Through this collaborative relationship, our hope is to continue to educate people about the critical population studies being conducted annually in these far-off islands and the many issues surrounding the Pribilof fur seals. Learn about Julie’s experience in the Pribliof Islands in this six-part blog series.
This morning we headed to another rookery named Polovina Cliffs. Today’s research goals were to flipper tag more pups and collect valuable data on adult females. This included weighing, taking photos of vibrissae (whiskers) for estimating age of the adult female, collecting a few blood samples for disease detection, tagging flippers as well as collecting the small punches of skin which are a result of when the tag is inserted into the flipper. One of the researchers, Dr. Bobette Dickerson, uses the DNA in that piece of skin to estimate the age each animal tagged. She explained that there is a small, repeat sequence at the end of each chromosome called a telomere. The telomere does not completely replicate after each cell division, therefore, telomeres get shorter as the animal ages.
The walk to the cliffs was a thin trail through tufts of grass and up small rolling hills. Many of the animals were resting on top of the cliffs, but we went around those animals to work with the seals on the beach to avoid the obvious dangers associated with a cliff. We started at 10am and began working a small rocky curve in the base of the cliff. We generally found about 20 females and pups and usually one or two males we let run back to the water. Males are large, dangerous and not part of the research goals of this ongoing study (sigh of relief). I can’t imagine trying to gather information on seals the same size as the Seattle Aquarium’s male fur seals, Al and Commander, who weigh 400-600 pounds. The male fur seals in the Pribilof Islands obviously aren’t trained to present their flippers for examination, open their mouth to brush their teeth, or hold still with no restraint for a blood draw like Al. (Al, you’re such a good boy!)
Each small group of seals would take anywhere from 10 to 30 minutes to flipper tag, then we would loosely pack up our gear, trudge about 50 yards to the next rocky section and do it again. We worked down the beach and had a short break for lunch. I thoroughly enjoyed this – and not just because I could rest. I actually had one of the least physically taxing jobs as an organizer of data and samples collected that day. Most of the researchers handled 90lb females and 20lb pups all day long (These people are freakishly strong with incredible endurance – I’m so impressed!) What I loved about lunch break was that I could sit and watch the pups play in the waves. Every time a wave rose the pups became visible in the green water and would surf down the wave. So cool. I still can’t believe I was actually in the Pribilof Islands!
We finished working the beach around 7pm and disassembled some small blinds (a little larger than a refrigerator) used to monitor and record the flipper tag numbers applied to the animals in previous years. We carried the blinds away from the cliff so they aren’t destroyed in the eminent weather that comes with being in the Bering Sea. Once back to the lab, I helped put ethanol on tissue collected to preserve each sample and process blood samples for later disease analysis. Samples are processed back in Seattle and sent out to other labs. The results are used by the scientists in their continuing research on this amazing species. And then there is the ever pleasant job of scrubbing poo off your rain gear. Gross, but so worth it!
It’s 4:30am and I just woke up to a strange scratching sounds and some high pitched animal noises. I’m later told it was probably an arctic fox (so cool). The foxes are still in their darker summer coats and aren’t yet sporting the fluffy white coats I usually associate with this arctic species.
Stay tuned for the next blog post, where Julie returns with the National Marine Fisheries Services to Zapadni Reef. To learn more about northern fur seals, come visit the Aquarium!