Grainy Pics Dept: Return of the Carnivores!

Ever since humanity made it past the large-animals-eat-us stage, history has not been kind to carnivores. But beginning in the mid-twentieth century - around the time Aldo Leopold famously watched a "green fire" die from the eyes of a wolf he'd just shot - some Americans began to regret the disappearance of the food chain's brawniest and most fearsome rung.

Gradually, through habitat conservation, establishment of wildlife corridors, and painstaking reintroductions, we started to encourage the likes of grizzlies, wolves, Florida panthers, California condors, and peregrine falcons to return.

It's been a long wait. But this week two bolts from the blue arrived. In California's Sierra Nevada, a graduate student's automatic camera took the first-ever photo of a wolverine in the Sierra Nevada. The ferocious, oversized weasels have been gone from California for at least 80 years. No one knows where this one came from - fitting considering these irascible animals' reputation for roaming enormous acreages, mostly above treeline, looking to fight for their supper.​

And three thousand miles away, in Massachusetts, a landowner shot a big gray dog, only to find it was the state's first gray wolf in 160 years.

It's a promising sign. Wolves tend to go walkabout when their home pack's territory starts to get packed. They, too, have a tremendous ability to wander, as sightings in Oregon over the past several years demonstrate. Most arrive from Idaho, undeterred by the swim across the Snake River. In January, a female wolf made the trip while wearing a radio collar, putting to rest any doubts about where it came from.

No one knows exactly where the Massachusetts wolf came from - presumably snowy Canada. But Canada is a large place, which brings up another recent news item: tracing people through the analysis of stable isotopes found in their hair. The technique gives a rough idea of where an animal lived based on hydrogen atoms contained in the rainwater it drinks. Since the stray wolf has already been shot dead, could a little more analysis narrow down where it came from?

Hat tip: the Knight Science Journalism Tracker