24 November, 1998
Tuesday, November 24th, 1998
Hi! What a FANTASTIC day! Hats off to Fred Atwood (another TEA teacher) for arranging a little "field trip" to visit with scientists studying seals at Big Razorback Island. What an awesome experience!
Fred and I left McMurdo around 10:15 AM, on Skidoos, bound for Big Razorback Island and the remote camp there. Don Siniff, from the University of Minnesota, started studying Weddell seals in this area of Antarctica in 1969. He was asked to begin this study, which turned out to be a long-term commitment…now almost 30 years in the making! At the time, Don was working on large animal (caribou and otter) populations. I'm sure that traveling to and working in Antarctica was an exciting opportunity for him!
We arrived at the remote camp in about 30 minutes…a gorgeous day to be traveling around in Antarctica! Blue skies and sunny….perfect weather for a field trip and a ride on a snowmobile. Almost immediately, I felt comfortable with the scientists we met at Big Razorback. They were so friendly and welcomed us to share their day! We helped them out by taking a group photo…they hadn't had many visitors, so they didn't even have a photo of their entire science team yet. Sadly, I don't remember everyone's names…we spent most of our day with Mike Cameron…our tour guide for the day!
What a tour guide he was…answering all of our questions, giving us so much information that I could barely keep up taking notes. This time I had brought along paper and a pen. I had learned from previous experience (like out at the Cape Roberts drill site) that I can't remember all of the facts and figures presented to me when I'm interviewing people, so I need to take notes. I quickly filled up my sheet with all of the facts Mike was telling us. I will share lots of these facts in just a bit.
We spent the rest of the morning with Mike, hiking around Big Razorback Island. He was telling us that they think that the islands around this area once formed a huge caldera from a volcano. The jagged tops of the islands reminded me of Crater Lake in Oregon, which is a volcanic caldera, too. All the while we were hiking, views of Mt. Erebus dominated the scene! It's such a presence when the sky is bright and sunny. Small puffs of steam rose from the summit of the mountain. How many photos of one mountain do I need to have? Who knows, but I'm sure that I'll have plenty of Mt. Erebus when I return home.
As we hiked at a leisurely pace with Mike, he explained the life history of Weddell Seals to Fred and I. We were able to see mothers and pups up close…which is a real treat. The Antarctic Treaty protects the animals here. Ordinarily people have to remain at least 5 meters from animals, and cannot approach them, or you will be in violation of the Antarctic Treaty. If their behavior changes, you must back off and leave them alone. If they approach you, which does happen, then you are to remain still and not bother them. Today was a little different. Since we were joining scientists working on a project, we had the opportunity to get a closer look. These scientists have permits that allow them to approach animals for tagging and other studies such as blood work. As a matter of fact, other members of Mike's team were taking blood samples as we worked our way around Big Razorback.
Several times throughout our hike, I saw pups and/or females slide into ice holes to reach the water, or saw them in the ice holes ready to come back onto the sea ice. The noises that the seals made were incredible to listen to. There were snorts, whines, helicopter sounds, barks, and an amazing assortment of communications. They came in different speeds, pitches, lengths, and emphasis. Some seemed like warnings, others like nervous habits…I'm sure brought on by our presence close by. It was all quite fascinating.
Mike is a graduate student who is studying the movement of seals within a certain study area. This is the southern most breeding mammal in the world, and a lot can be learned by doing a long-term study such as the one Don's been working on since 1969. Mike will be looking at survivorship and reproductive rates and parameters of these, as well as immigration and emigration (moving in and out) of this study area and how that affects population numbers inside the study area. For this parcticular project, the study area stretches from Scott Base (near McMurdo) all the way to Cape Evan (where Robert Scott's hut is located). It's a huge area, and this involves a lot of time and effort on the part of the science teams, to monitor the seals and make sure they are all tagged.
Data is recorded on small hand held computers, and later transferred to laptop computers back at the remote camp. At the present time there are 30 years of records, with 120,000 individual animal sitings, and over 13,500 animals tagged. Scientists have learned so much because of the long-term data base of information they have collected.
Weddell Seal pups are about 60 pounds at birth. By the time they are weaned from their mother (about 6 weeks later) they can weigh 180 pounds. The milk they drink from their mother is heavily laden with fat. There is a great energy transfer from the mother to pup. For every 2 pounds that a mother seal loses while nursing a pup, the pup itself gains 1 pound. Pups do not have the blubber that adults do, so they are kept warm by their soft thick fur, called "lanugo" fur. Adult seals have blubber to protect them from the cold. The lanugo fur was wispy, soft, and light gray in color. Within a short period of time the pup loses this fur and gains the weight (and fat) it needs to survive the icy cold water surrounding Antarctica. We saw many pups that were quite large and already losing the lanugo fur.
This study area had traditionally had around 390 pups born in it each year. Last year was a boom year with 550 pups total. In one 2-day period of time, over 200 pups were tagged. This year 489 pups were recorded and tagged. One theory Mike gave us for the increase in population was that 7 years ago, it was a pretty good year to be a pup. The survivors of that time period have done well. It usually takes seals around 7 years before they have pups. Peak "pupping" time here in the Erebus Bay area is usually Halloween.
Pups do not have the greatest chances of survival. Scientists have learned that 15% of pups die between birth and weaning. 50% of the pups die between weaning and the time they are one year old. After one year survivorship increases. By the time they are adults (between 5-7 years old), they have a 98% chance of survival. Being a pup is dangerous business. As the pups grow to be about 3-4 weeks old, mom starts to take the pup to water. The pup usually bawls (cries out) in distress. Finally it gives in and joins mom in the water. Mom takes the pup over and over to swim and forage for food. Often it is hard for pups to get back out of the ice hole and water onto the sea ice. Mom has to help out by using her teeth to rough up the surface of the ice hole, making it easier to get out, or by giving the pup a boost up out of the water. Even so, some pups do drown.
Mom leaves the pup after weaning and the pup usually bawls for a week. By this point, the pup has gained sufficient weight and fat and is a butterball. It has the tough job of finding its own food in the ocean. The pups spend about 4 years away from the study area, learning to survive on their own and growing up a bit. Eventually they come back to the study area where they were born.
I also saw male seals with radio transmitters attached to their backs. These transmitters are attached to the seal's body using a sort of super glue. The transmitters eventually fall off as the seal molts later in the season. Because of the transmitters, scientists can hear a signal if the seal is up on the ice, they can study behavioral data, and there is also a depth pinger that gives information about how far they dive down under water. We saw the radio towers that are temporarily put up on the sea ice, during the data collecting part of the summer season. The battery and computer are stored in a Coleman cooler…they use bungy cords to keep the cooler closed tightly. Solar panels are used to charge the battery, making use of a very abundant source of energy here in Antarctica…the sun! An antenna is located at the top of a pole, and the pole is secured by tether ropes coming out in several directions and anchored in the ground. Quite an operation.
Arriving back at camp at around 1:30 PM, we were treated to a home-cooked Mexican lunch by Mike…man of many talents! It was so much better than our usual lunches in town! And all cooked on a Coleman two burner stove! The biggest treat for me was Chips Ahoy cookies. I haven't had a good cookie since leaving Christchurch, New Zealand! I could have eaten the whole package! The field camps get priority for all kinds of goodies, and Mike was telling us that "Pringles" potato chips are one example of things reserved for "deep field camps" or more remote sites. Back in McMurdo last night, we had the first "freshies" in weeks. Freshies are fresh fruits and vegetables. A plane had arrived, bringing with it lots of GREAT fresh stuff. Freshies are usually more readily available in the field camps. I guess it's their reward for being stuck out in remote areas.
After lunch Mike, Fred, and I were joined by Dan, another one of the scientists on the team. We rode on snowmobiles to two nearby islands…Tent Island and Inaccessible Island. The purpose of this afternoon was to check every seal we saw to see if it had the proper tags still on its flippers. Sometimes the tags break off, and have to be replaced. Each seal has two tags…one on each flipper. The tags have varying colors and numbers. The color and number is recorded in the data base and used to log information about the seal population in the study area.
I wish I had kept track of how many seals we checked out this afternoon. Tent Island proved to be the better area for the seals…maybe because it had so many cracks in the ice for the seals to come up through. We found quite a few with broken or missing tags, and I got to watch them re-tag these animals. Dan would carefully approach these seals with a cone-shaped rubber bag, with rope handles. As he slowly came toward the seal, waiting for just the right moment, Mike would distract the animal. Dan moved quickly and carefully to place this bag over the seal's head and then he had to sit on top of the seal to keep the bag on. Sometimes it reminded me of a rodeo event. His aim was terrific and he had to bag quite a few of them.
While Dan was doing his part, Mike worked quickly to remove any old tags (or remnants of tags) and put new ones on each flipper. He recorded this information in a log book. The device he used to put the tags on reminded me of something you'd use to pierce someone's ears…only much larger. The sharp end of the tag was cut off after piercing the flippers…to prevent the seal from hurting itself with it. The whole tagging process didn't take that long for each individual animal, but we rode around the islands for several hours doing this.
Before I knew it, it was 5:15 PM and the afternoon had slipped away. I was very reluctant to leave this beautiful location and the fun of this project. I thoroughly enjoyed this adventure and I want to thank Mike and Dan for a great afternoon. Thanks especially to Mike who put up with the questions of two teachers….and did a FANTASTIC job!
Fred and I sped off on our Skidoos-headed back to McMurdo. It took us about 45 minutes to get back to town. By the time we secured and covered the snowmobiles, and walked up to dinner, it was nearing 7:00 PM. I ran into my paleomag team and found out that Gary had spent the afternoon at the Cape Roberts drill site, so we needed to drill samples this evening. Fabio and I worked for about an hour, with Sonia helping Gary inside the core sampling room. The work went much quicker with four people helping out.
Later, we all went to a party at the scuba diver's building. It was to celebrate Hunter's (one of the divers) birthday, along with Fabio's. A good chance to unwind with friends and listen to some music. A great end to a WONDERFUL day! Talk with you tomorrow.
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