This journal is brought to you by...
This journal is brought to you by...
- Kim Brothers and her 2nd grade class at Riverwood Elementary
- Mrs. Buoni and Mrs. Blaizel's Kindergarten class at Saint Agnes Academy and Saint Dominic School
- Mrs. Burns and her 3rd grade class at Riverwood Elementary
Observations Lead to a New Research Question
While we were doing all this data collection, our team of scientists was making careful observations. Dr. Burns observed that many of the female seals we would have liked to put tags on could not be tagged, since they were not done molting. Seals that weren’t done molting were still shedding their fur, so if we glued tags to them, they would have just fallen off—and not collected any useful data! So after noticing that these seals were still molting very late in the season (February), Dr. Burns asked a simple question – WHY? She also wondered (hypothesized) if these ‘late molting seals’ had had a pup earlier in the season.
Don’t you just love science? One scientific question often leads to another!
Dr. Burns’ question brought up an important new research question: ‘Is there a link between having a pup and growing a new fur coat?’ Our new research question meant we needed to collect MORE data!
Initial data chart. What does this chart say to you? Photo credit: Dr. Jennifer Burns
This graph helps us visualize the relationship between molt status in January and pupping the previous October. What do you think this chart is saying? Can you analyze the data?
It looks like a lot of seals who had completed the molt by mid-January had not pupped earlier that year, and a lot of seals that had not started to molt by January (they would molt later in the year) had given birth earlier in the year.
But we needed even more data!
The Process Begins
How do we get data for our new study? Well let me tell you, a lot of work and time goes into answering our research question! If you want to study seals, first, you have to find some seals to study!
So, let’s start with a bit of background information.
Our field season is divided into two parts: mid-November to mid-December and mid-January to mid-February.
During November/December, the team selects seals to study for that field season. And, since we are looking for a connection between pupping and molting, we are only looking for female seals, because they are the only ones that can have a pup, right!
With the help of a few other seal research teams who let us know where these seals were last seen, we create a ‘plan of action’ and start by venturing out to the seal colonies.
Haul out sites for Weddell seals. The sites are marked with red dots and McMurdo station is marked with a red star. Photo credit: Brad Herring, edits made by Alex Eilers
Base camp, highlighted by the red star, is McMurdo Station. The other red dots show the location of the seal colonies, where seals are likely to haul out.
Antarctica is not really the type of place where you can just hop in a car and cruise to the nearest seal colony. Instead, we use snowmobiles and helicopters!
Snowmobiles and helicopters help us travel safely in Antarctica. Photo credit: Alex Eilers
Finding seals – ID tags are helpful
Once we get to the seal colonies, we need to find the right seal, and that’s not always easy because most of the seals look the same.
Take a look at this picture. Do the seals look very different to you?
Seals hauled out on the ice. Photo credit:Alex Eilers, MMPA Permit # 17411
Thank goodness for the flipper or ID (identification) tags!
Another team of scientists has been collecting data on the Weddell seals near McMurdo Station for about thirty years. That’s a long time! Not only does this group collect data, they share it too! And, believe me; they have collected a lot of helpful data. Here’s some of the information our team can learn about individual seals:
- Where or in what colony has the seal been seen?
- Is the seal male or female?
- The age of the animal?
- If the seal is female, has she had a pup this year? If so, when did she give birth?
- How many pups has a particular seal had in her whole life?
Flipper tags are generally red, yellow or blue in color. These tags are clipped (like an earring) to both of the seals’ hind flippers. A unique number along with the country code is included on each tag. For example, the blue tags in the picture below have the number 1959 on one side (the seal’s unique ID or number) and USAP (which stands for United States Antarctic Program) on the other. If you were a researcher from another country, you would know that a scientist from the United States Antarctic Program has tagged and collected information about that particular seal.
Flipper tags attached to seals’ flippers and close up view of tags. Photo credit: Alex Eilers, MMPA Permit # 17411
Now, back to finding the right seals. We are looking for seals in one of three categories.
Seal categories
Our team will be collecting and comparing data on three categories of seals. Here are the categories:
Female seal study categories: skip breeders, early moms and late moms Photo credit: Michelle Shero, MMPA Permit # 17411
- Skip breeders, sometimes just called ‘skips,’ are seals that had a pup in the past but did not pup this year. In other words, these females skipped a breeding cycle.
- Early moms are seals that had a pup early in the season (around mid-October).
- Late moms are seals that had a pup late in the season (around early November).
Here’s a fun fact! Did you know that all Weddell seals in McMurdo Sound are born in October or November? How many of you share a birthday with the Weddell seals?
Now, after we travel to the seal colony and find the right seal, we can begin collecting data!
Find the seals again
During the November/December field season the team will clip a small VHF (Very High Frequency) tag on the hind flipper of each seal. VHF tags are used to pinpoint the seals’ ‘exact’ location. Each tag has a unique frequency that can be tuned in to using a scanner. The tags emit a 'ping' every second and that 'ping' is picked up by the scanner/receiver. So the team needs to fly over or snowmobile close enough to the seals for the scanner to pick up the VHF signal—and voila, a previously tagged seal should be near.
Here is a VHF tag attached to a seal’s hind flipper. You can see just how small the tag is! Photo credit: Roxanne Beltran, MMPA Permit # 17411
Here we are scanning for seals! Photo credit: Dr. Jennifer Burns
It also helps that the team ‘marks the seal’ during the first part of the season.
Do you think this mark will be easy to see? Photo credit: Greg Frankfurter, MMPA # 17411
Can you identify this dye mark as the musical notation ‘treble clef?’ We named this seal ‘Treble’ and used the ‘treble clef’ dye mark to more easily identify her.
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