Tuesday, February 17, 2009

Another death in the Happy Zebra Clan

It's sad when any hyena dies.
It's even worse when it's a hyena you're particularly fond of.
It's hardest of all when it's a tiny cub.

Last night, we came upon what originally seemed like an idyllic scene at the Happy Zebra den. Sawtooth - one of my favorite hyenas - was grooming her tiny black cub Neverland, who was born fewer than 20 days ago. The cub, however, wasn’t moving. We could see that his head was covered in blood.

After the vigorous bath didn’t breathe life into Neverland, Sawtooth stood over her motionless cub, looking confused. Several minutes later, she lay down in the denhole, just a meter or so from Neverland's body.

None of the other hyenas at the den seemed to understand why the cub was so very still. Over the next hour, several of them came over to sniff and prod the dead cub. Snapper, a Happy Zebra subadult, even picked Neverland up and carried him around for a while before she lost interest, placing him carefully back where she had found him.

Our necropsy showed that Neverland had died from massive head trauma just an hour or two before we arrived at the den. His entire skull and jaw had been crushed. While adult hyenas have extremely robust skulls, a young cub's skull still has a lot of developing left to do, and is surprisingly fragile.

The most likely scenario? Infanticide by another hyena. It’s brutal, but it happens in many species. When food is a limited resource, any extra mouths to feed mean less nourishment for you and your offspring. One way to deal with such competition is to kill it. It’s hard to know how often infanticide happens among hyenas, and we’ll never find out all the details surrounding Neverland's death.

The sad truth is that fewer than half of all hyena cubs survive to adulthood. We’ve got over fifty cubs here at Serena…let’s hope they can beat those tough odds.


Dana-Phoenix, Arizona said...

Sorry to hear of Neverland's death Kate. It's like loosing a member of the family I know.

wall said...

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Joel Sammallahti said...

Love the blog. Question: why didn't the infanticidal individual eat the pup after killing it?

Kate said...

Honestly, we don't know a lot about infanticide in hyenas. I can tell you that we rarely see hyenas eating dead hyenas (no matter what the cause of death).

In many species, cannibalism can spread disease, so it's eliminated (or at least limited) by natural selection. It's also possible that hyena meat just doesn't taste good...I've heard that bitter acid builds up in the muscles of carnivores, making their flesh very unpalatable.

In any case, infanticide is often less about an individual's current state, and more about possible future benefits. In other words, an individual doesn't necessarily have to be hungry to commit infanticide.

Hope that helps a bit!

Michigan State University | College of Natural Science