The Coming Sewer Gold Rush

Oct 12, 2017
Originally published on October 12, 2017 11:39 am
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OK. Now a story about the social lives of big cats. Mountain lions, also called pumas or cougars, have always been thought of as loners, but a new study reveals these cats actually have a hidden social life. NPR's Nell Greenfieldboyce reports that they frequently get together with neighbors to share a meal.

NELL GREENFIELDBOYCE, BYLINE: Mountain lions have been studied in North America for decades.

MARK ELBROCH: We have assumed that they're solitary killing machines and they're kind of like robots, they're all the same.

GREENFIELDBOYCE: Mark Elbroch is with a nonprofit called Panthera. He says scientists thought mountain lions came together only rarely.

ELBROCH: They were fighting over territory, or it was about courtship and mating between males and females, and there was really no other reason to come together at all.

GREENFIELDBOYCE: It turns out that's not true. Elbroch spent about three years tracking mountain lions in Wyoming with GPS collars that let him watch their movements in almost real time. When he saw big cat stop for a while, maybe because it had killed an elk, he and his colleagues would rush to the spot and set up motion-activated cameras. What they saw and heard astonished them.


GREENFIELDBOYCE: In this video, two females are facing off at a carcass. They snarl and swipe at each other.


GREENFIELDBOYCE: Then they settle down and peacefully share the meat. The researchers saw this happen over and over again. All the mountain lions shared food with neighbors.

ELBROCH: That in itself was shocking, you know, that there wasn't a lone mountain lion that didn't interact with anybody. They all participated.

GREENFIELDBOYCE: And who did they share with? In the journal Science Advances, the researchers say the lions followed a pattern of direct reciprocity - you give me some food, and later I'll give you some.

ELBROCH: It just highlights the fact that even a species like mountain lions, that we have studied for so long, we know so little about.

GREENFIELDBOYCE: And it makes him wonder about other supposedly solitary species. Nell Greenfieldboyce, NPR News. Transcript provided by NPR, Copyright NPR.