A roar broke the silence of a dead winter's night. When I heard the noise, I shot up and tossed back the hood of my sleeping bag, which I had pulled over my head to cut the chill. From my bed up in the research tower, I looked down at the water hole 20 feet below, now black since the moon had set several hours ago. This was my home during my elephant field season, and it offered a great view of elephants in action day and night.

I couldn’t make sense of the situation in the dark, so I reached for my night-vision scope. The shadows of four elephants came into view, too few for an extended family group. I watched an adult female marching up and down the most popular drinking spot, a concrete water trough fed by a natural spring. She swung her trunk back and forth, keeping the other three elephants away while she focused on the water. I zoomed in on her head, squinting for a clue to her identity. She lacked a left tusk and, when I looked at her left ear, I saw the shape of a “W” missing, the result of natural wear and tear. It was Wynona.

Now I could see that her companions were her male calf, her grown daughter and a granddaughter. But why weren’t they with the rest of the group? Something was amiss. I turned my attention back to Wynona, now skimming the water with her trunk, clearly agitated. What was she doing?

In the next moment, I saw the cause of her concern. A tiny head popped up out of the water, and Wynona dragged a wet and confused little calf out of the trough. I couldn’t believe it: Wynona, one of my favorite elephants, had a new baby.

Wynona had been looking pregnant since the beginning of the season, but I hadn’t thought that I’d be lucky enough to be around for the birth, which must have happened sometime in the 48 hours since the family’s last visit. In the 20 summers I’ve spent studying elephants at Mushara, a water hole in Etosha National Park, in north-central Namibia, I had never observed a birth here. The cows may have avoided giving birth at the water hole because the clearing surrounding it was too open, which would make newborns vulnerable to hungry lions and hyenas. Whatever the reason, the new calves I’d seen had usually had a few days to get their footing. By then, they and their mothers had rejoined the rest of the family.

Female elephants live in extended family groups of up to 30 members, who spend much of their lives near one another, bathing, foraging and socializing. But even before the birth of Wynona’s little one, her family relations seemed slightly off. Throughout the field season, she had been ostracized, even harassed. One day, just before the birth, I observed another elephant, named Susan (also pregnant), pushing Wynona away from the water hole. As far as I could tell, Wynona did nothing to instigate the bullying, which culminated in a trunk slap to her retreating rear end.

I also noticed aggressive behavior toward elephant calves. These little ones are normally coddled by everyone—caring moms, watchful aunts, playful siblings and cousins. But some calves weren’t receiving this support. I had even seen Susan, with a whack of her trunk, pushing another female’s baby away from the rest of the family. Such behavior made me wonder why Wynona’s extended family was absent for the birth of her calf. Although she and her immediate family may have just fallen behind the group, I was starting to consider another, darker possibility.

***

For two months each summer, my husband, Tim, and I set up camp at Mushara in the northeast corner of the park with a small research team. To get a good view but still give the elephants some space, we position our tower and camp behind a concrete bunker set back from the elephants’ prime gathering spot. After we remove the mice and snakes that took up residence in the bunker during our absence, we settle in to study our elephant subjects.

I always look forward to these summers with my field team of Stanford students, University of Namibia students and volunteers. During the academic year at Stanford, my previous work on seismic communication among elephants informs my studies of acoustics. I test new vibrotactile delivery designs in search of a new kind of hearing aid. But nothing beats spending summer nights at Mushara under the Milky Way during Etosha’s winter.