A Leopard Seal Mother’s Love Transcends Death

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LLeopard seals have a reputation for being aggressive. Virtually alone at the top of the Antarctic food chain, these territorial predators feast on penguins, squid and other seals, and have even been known to attack humans. Now, new research is shedding light on the softer side of pinnipeds.

For the first time, scientists have observed mother leopards caring for their deceased offspring. This is a rare phenomenon known as “postmortem attentive behavior” or PAB. Chimpanzees, whales, elephants and other mammals have been observed participating in this behavior, but it had not previously been documented in leopard seals.

Postdoctoral researchers Emily Sperou and Renato Borras-Chavez of the University of Rhode Island observed leopard seals in Patagonia, Chile, and published their findings in Polar biology. They observed mothers with dead puppies nosing at them, carrying them in their mouths, showing territoriality around their corpses, and even carrying them between ice floes. “This was a unique behavior to observe,” Sperou said in a statement.

Some of the mothers observed had PAB long after the death of their puppies. In fact, one mother cared for her puppy’s corpse for 20 days, one of the longest episodes of PAB on record.

While the question of whether or not this heartbreaking behavior constitutes something that we humans would recognize as “grief” is probably best left to philosophers, the debate over whether this trait is adaptive is still open among biologists. The authors of this article fall squarely on one side. “It’s actually a maladaptive trait,” Sperou said. “This behavior is not beneficial for the animal.”

Read more: »How animals understand death»

Researchers point to a potential chemical culprit: the hormone oxytocin. After birth, oxytocin strengthens the maternal bond, and once the faucet is turned on, it may not be so quick to turn off, even when their offspring die. In other words, PAB could represent a kind of empathy transfer that prevents seal mothers from releasing their dead pups.

Some scientists have also hypothesized that PAB in other marine mammals, such as whales and dolphins, is a consequence of the brain being larger and evolving for social interactions. In this model, mothers whose offspring have died are more social creatures who strive to protect their offspring even after they expire.

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Main image: Sperou, ES, et al. Polar biology (2025).

• Jake Currie

  Published on November 20, 2025

  Jake Currie is a writer based in Brooklyn, New York.