While it may seem as simple as sticking a GoPro in the water, capturing videos of marine animals in Antarctica is no easy feat. Postdoctoral student Kaitlin Allen and her Woods Hole Oceanographic Institute (WHOI) can’t see what they’re filming in real time, so the team has no idea what’s being recorded until they take out the device and plug it into a laptop, Allen says. popular science.

Sometimes images don’t capture anything important. Other times, however, it records crucial animal dynamics that humans rarely witness. A recently released video that Allen and his colleagues captured in 2015 (with proper permission) is a case in point. The remarkable and certainly adorable series of clips featuring a thick Weddell stamp (Leptonychotes weddellii) the mother and her pup swim under thick sea ice, occasionally sticking their heads out of a hole to breathe.

“It’s essentially a swimming lesson,” Allen explains. “Many marine mammals don’t teach their pups to swim, especially seals. They nurse them for a while, then wean them, and then the pups are left alone to figure it out. But Weddell seals in Antarctica do.”

Baby Seal Swimming Lesson

The species represents the southernmost breeding mammal on Earth. They are extraordinary divers, who can hold their breath for more than an hour. However, since pups are born on sea ice, they must develop their diving skills over time. In the images, the mother seal encourages this by waiting for her pup in the water, who will eventually follow her in search of her milk.

“They’re not doing much, but this pup is having to hold his breath in the water for the first time and learn to navigate on sea ice,” Allen says. “He needs to learn how to get back to the breathing hole, how to find the breathing hole when he needs to breathe, how to get in and out of the water. The mom just keeps the puppy company. She will help them get out of the water if necessary. They will scrape the ice with their teeth to create more traction.”

In addition to swimming lessons, Weddell seal mothers also transfer a large amount of energy to their pups through milk without eating anything themselves. In less than two months, a mother Weddell seal loses about 300 pounds. Specifically, Allen and his colleagues are studying the transfer of iron from mother to calf, which is what allows the species to hold its breath for so long.

This enormous loss of iron on the part of the mother would be very harmful to humans. But it’s clearly working for Weddell seals, which is why Allen and his team are currently investigating the seal conundrum.

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