Disease-carrying mountain goats threaten ancient bighorn sheep herd

A unique herd of bighorn sheep has survived commercial hunting, human expansion, and isolation. Now it faces a new enemy.

Signs of bighorn sheep were scattered inches away from the cliff edge: Dirt packed down from where they slept, round droppings, and a still-pungent smell. The animals themselves were gone, melting away into distant layers of mountain and rock.

Steve Kilpatrick, a retired biologist now leading the Wyoming Wild Sheep Foundation, was in the mountains on the border of Grand Teton National Park in August surveying sheep as part of an annual effort to keep tabs on its dwindling population.

Fewer than 100 sheep now comprise the ancient Teton Range herd in northwest Wyoming—one of the most unique in the West. And biologists say it is on the brink of blinking out.

The threat list begins as a familiar mixture of habitat loss,

DON'T MISS THE REST OF THIS STORY!
Create a free account to continue and get unlimited access to hundreds of Nat Geo articles, plus newsletters.

Create your free account to continue reading

No credit card required. Unlimited access to free content.
Or get a Premium Subscription to access the best of Nat Geo - just $19
SUBSCRIBE

More on This Topic

These animals thrive in extreme mountain conditions—here's how
From poachers to protectors, meet the rangers of Masjed Mountain
Disease-carrying mountain goats threaten ancient bighorn sheep herd

Go Further

Subscriber Exclusive Content

Why are people so dang obsessed with Mars?

How viruses shape our world

The era of greyhound racing in the U.S. is coming to an end

See how people have imagined life on Mars through history

See how NASA’s new Mars rover will explore the red planet

Why are people so dang obsessed with Mars?

How viruses shape our world

The era of greyhound racing in the U.S. is coming to an end

See how people have imagined life on Mars through history

See how NASA’s new Mars rover will explore the red planet

Why are people so dang obsessed with Mars?

How viruses shape our world

The era of greyhound racing in the U.S. is coming to an end

See how people have imagined life on Mars through history

See how NASA’s new Mars rover will explore the red planet