Inhabiting the Ross Sea—as far south as McMurdo Sound—Weddell seals (Leptonychotes weddellii) have the most southerly distribution of any mammal on Earth. Scientists began studying a breeding population of Weddell seals in 1968 and quickly found out these pinnipeds don’t always have it easy. Giving birth and raising young is particularly challenging in Antarctica’s extreme conditions, forcing Weddell moms and pups to bear sub-zero temperatures and prevailing winds. How do they manage to do it so gracefully? (OK: they’re admittedly way more graceful in the water than on land.) To find out, NOVA hosts Caitlin and Arlo travel to an Antarctic Weddell seal colony during pupping season. Once there, they meet with seal biologist Jay Rotella—and the downright adorable newborn seals he studies.
How Antarctica’s Cutest Baby Seals Grow Up
Published: February 5, 2020
Caitlin Saks: It seems like everyone has an idea of what Antarctica looks like.
Arlo Pérez: For us it was this endless landscape of white, as far as the eye could see.
Caitlin: But when we got here, we were greeted with something different. A wild and varied terrain.
Arlo: One its most striking features is its sea ice.
Caitlin: It’s also one of the most dangerous—covered in cracks that open straight to the freezing water below.
Arlo: But if you take a closer look at these cracks you might be rewarded with the sight of a creature that has made them their home.
Caitlin: This is what we've been waiting for. This is what we've been training for all week long. We’re finally going to go out on the sea ice and meet with a scientist who is studying seals out there.
Radio: Yankee six-zero-one stand by.
Caitlin: That means don’t say anything right?
Arlo: Whenever someone falls over into a crack, they actually name the crack after them. If I could have a crack named after me, that would be great. You know you'd be like “Crack Arlo.” Or “Arlo's Crack.” Which kinda has a different ring to it.
Caitlin: Jay Rotella and his team are researching seal families – a study that’s been going on for just over 50years.
Caitlin: Is it trying to find milk right now?
Jay Rotella: Yeah, so the two nipples are back toward us, and he or she may find them.
Caitlin: You can do it buddy, you’re close.
Jay Rotella: That baby was 66 pounds on average that's pretty typical. And it will be two hundred and fifty pounds or so 220 pounds within a month.
Caitlin: Oh my gosh!
Jay Rotella: So they'll go from about the size of a second grader, to an NFL football player in 30 days.
Caitlin: My friend Arlo wants to have a crack named after him. But you have to fall into a crack to do that. So what do you think about a seal, can we have a seal named after him? Can we name him Arlo?
Jay Rotella: We just have to find a boy seal and youcan name it Arlo, that's fine.
Caitlin: Is that a boy seal?
Jay Rotella: Well we can check.
Jay Rotella: Arlo’s a boy!
Caitlin: Arlo’s a boy!
Arlo: The seal colony is in the middle of one of the most breathtaking landscapes—where the sea ice flows around an island. Here, pressure builds in the ice, creating these towering icy sculptures, appropriately called pressure ridges.
Arlo: Now, what is probably most stunning about these pressure ridges is how similar it actually looks to water. You actually look at it, and you can imagine, like, waves crashing against the surface.
Arlo: But they’re not just cool to look at. They’re actually a lifeline for seals. Because among these ridges are weak points in the ice - cracks that allow the seals to get in and out of the water.Which probably means walking through here…
Arlo: ...is a pretty stupid idea.
Arlo: That sounds like it was crackin’!
Arlo: Watch out for this crack!
Jay Rotella: When you think about where we're living and what that pup is about to face, only about two out of ten will survive to be adults. The scientist part says I hope you get all the help you can. That’s one of the things mothers do for their babies. So we’re trying to figure out the recipe for success. These female seals are very faithful to these places for their pupping. So they'll come in and during October and then they'll be here and raise their pups for a month.
Caitlin: To figure out the recipe for seal success, jay and his team tag the newborn seals...
Jay Rotella: I can see her tag numbers. She's wearing a pair on each of her hind flippers.
Caitlin: …and this allows them to track the seals through their lives.
Jay Rotella: When did this female start breeding. Which years did she have pups or not have pups. What were the ice conditions like. And try to figure out why are some years better for making babies than others.
Caitlin: In the last 50 years, they’ve followed over 25,000 seals, and that has allowed them to learn a lot about this population.
Jay Rotella: They look kinda cumbersome up here. You know they kind of flop along on their belly to move around. But when you see them in the water swimming, they become these athletes and you realize yeah they've—they have this very dual existence.
Caitlin: These seals spend a lot of their lives in the water. Here, they fight for territory, look for food, and apparently... Sing.
Caitlin: I have to say, they make some amazing sounds!
Jay Rotella: Yeah they make some canary chirps and they make some big booms. Really great sounds. It's almost like they're singing these bird songs under water.
Caitlin: Turns out, they can be pretty chatty up on the ice, too.
Arlo: Oh, hey there!
Arlo: Here in Antarctica, seals don’t have predators on the ice. Unlike most big mammals, you can get surprisingly close to them in their natural habitat. And because of that, you can capture some deeply intimate moments. And… a lot of poop.
Caitlin: Yuck… gross.
Arlo: That said, I come across one moment that stands out above all the rest..
Arlo: So we’re watching this really incredible moment happen, the mom is trying to convince the pup that it’s time to learn how to swim.
Jay Rotella: Earlier we were talking about things mothers do with milk. One of the other things they do is, some mothers go in that water and seem to just sit there and call to the pups and won’t come out and nurse them until the pups come in is what it looks like. And so we're wondering if some mothers make their pups swim, so to speak. Some pups hardly ever swim like ever in 30 days. And you think well that's kind of part of being a seal. Maybe you should learn to do that.
Arlo: This pup couldn’t build up the courage to take his first plunge.
Jay Rotella: Other pups start swimming maybe as early as a week old. And are in for hours and hours a day. So we're kind of curious because you try and drink that milk and get big. And if you go in cold water maybe you'll lose some weight. And so we're kind of curious if your mom makes you big and heavy at birth and then gives you lots of milk, are you willing to go swim more?
Caitlin: Jay and his team are still searching for answers. The team lives out here for a couple months every year.
Arlo: So this from New Zealand?
Student: We think so because it says minced beef on it, and it doesn’t seem like an American thing to say.
Jay Rotella:You’re gonna share?
Caitlin: It’s cozy living conditions.
Caitlin: Who’s the chef? Do you guys sit down for dinner like this all together every night?
Jay Rotella: We do, every night.
Caitlin: But I am impressed by how tight the seal team is. They’re like a second family for each other.And they seem to deeply enjoy the work.
Kaitlin Macdonald: We were talking about earlier, it’ s really fun watching the pups grow up. I love it! I've seen one actual birth and then there have been a few times that where you pass by a mom, and you go do something and then you look back and you're like “wait she didn't have a pup when I walked by a minute ago!”
Caitlin: That’s exactly what happened to us.
Arlo: After dinner, when we went back outside, a new pup had been born… just in the short time we’d been away. A tender moment… found, of all places, in one of the harshest environments on Earth.
Caitlin: Everyone has an idea of what Antarctica looks like.
Caitlin: Hey Arlo.
Caitlin: Get any good photos?
Arlo: Yeah, I’m also being one with the seals.
Caitlin: But as we sat there watching the seals, we realized, there is so much more to this place than we could have ever imagined.
Arlo: It feels magical.
Arlo: You know, it’s really beautiful, if you ignore all the poop and blood.
Caitlin: I want to show you something
Arlo: And it’s a spot where a piece of us will always stay.
Caitlin: I named that one Arlo, it was born just a few days ago.
Caitlin: So now we don’t have to name a crack after you, and you don’t have to fall in one.
Arlo: Okay, okay, okay… let’s not go too far.
Caitlin: I don’t think I’ve ever stopped to just watch stuff like this before.
Hosted by Caitlin Saks and Arlo Pérez
Editor/Digital Associate Producer: Arlo Pérez
Producer: Caitlin Saks
Field Director/Cinematographer: Zachary Fink
Executive Producer: Julia Cort
Coordinating Producer: Elizabeth Benjes
Project Director: Pamela Rosenstein
Post Production: Jay Colamaria
Production Assistance: Matthew Buckley, Emily Pattison, Sean Cuddihy
Audio Mix: Heart Punch Studio
Director of Audience Development: Dante Graves
Senior Digital Producer: Ari Daniel
Audience Engagement Editor: Sukee Bennett
Outreach Manager: Gina Varamo
Special thanks to the United States Antarctic Program
Additional Footage: Alasdair Turner, Jay Rotella, Jean Pennycook, Jesse DeVoe, Mary Lynn Price, McMurdo Oceanographic Observatory, Paul Cziko, Robert Robbins, Steven Rupp
Music: APM, Axletree/Free Music Archive
© WGBH Educational Foundation 2020